A Lecture Note on

AGROFORESTRY (HRT-406)
B.SC.AG. 7TH SEMESTER
 Course Syllabus of AGROFORESTRY
B.SC.AG. 7TH SEMESTER
Course Code: HRT 406
Credit Hours: 2 (1+1) Full Marks: 50 Theory: 25 Practical: 25
OBJECTIVES
Upon the completion of this course the student will have basic knowledge on principles and practices
of agro forestry systems
I. SYLLABUS
Concept of Agro-forestry: Definition, importance and scope. Roles of trees in fulfilling the basic
requirements of people, characteristics of trees for Agro-forestry development and tree improvement.
Agroforestry System (AFS): Classification of the Agroforestry system (AFS) and over-view of Arsine
Nepal and similar agro-eco-zoning in the World. Tree-crop- interaction: Nature of interactions, factors,
types, quantifying interactions. Soil management under AFS: Soil-water conservation approaches, soil-
fertility management. Designing AFS: Conceptual framework for designing AFS. Project development:
ICFAF‘s diagnosis and design, diagnostic methods and tools used in AFS. Management of trees in AFS:
Tree-management, agricultural management, silvicultural and management operations. Quantifying
agroforestry products.
II. COURSE OUTLINE
A. Lecture
S.N. Topics No of lectures
1. Concept of Agroforestry: Definition, importance and scope. 1
2. Tree selection and improvements: 2
2.1Roles of trees in fulfilling the basic requirements of people
2.2Characteristics of trees for Agroforestry development and tree
improvements
3. Agroforestry system (AFS): 2
3.1Classification and over-view of Agroforestry System ( AFS)
3.2Overview of AFS in Nepal and similar agro-eco-zoning in the world
4. Tree-crop-interaction 2
4.1Factors and types on nature of tree-crop interaction
4.2Quantifying Agroforestryproducts
5. Soil management under AFS: 2
5.1Approaches of soil-water conservation
5.2Soil-fertility management
6. Designing AFS: 2
6.1Conceptual framework for designing AFS
6.2Factors affecting AFS
7. Project development: 2
7.1ICFAF‘s diagnosis and design
7.2Diagnostic methods and tools used in AFS
8. Management of trees in AFS: 2
8.1 Management of trees in Agriculture
8.2 Agricultural and Silvicultural management in relation to crop
Total 15

B. Practical
S.N. Topics No of lectures
1. Tree selection and identification for AFS at different areas: 3
1.1 High Hills
1.2 Mid Hills
1.3 Terai
2. Practice in contour farming system 1
3. Preparation ‗A‘-frames and determines contour lines 1
4. Lay-out of a soil-water conservation systems. 1
5. Nursery establishment for AFS 3
5.1 Collection and identification of seeds of Agroforesty trees
5.2 Preparation of nursery bed for Agroforestry tree
Seed sowing for Agroforestry trees
6. Tree-clinic for AFS. 1
7. Training and pruning for Agro forestry trees 1
8. Height and canopy measurement for selected Agroforesty trees 1
9. Different AFS development (SALT and home garden) 1
10. Establishment of Agroforesty farm at Agriculture and Forestry University 1
(AFU)
11. A visit to success story of Agroforestry project(s) at local level 1
Total 15

REFERENCES
Chaundawat, B.S. and S.K. Gautam. 1996. Text of Agroforestry. Oxfood and IBH Publishing Co. Pvt.
Ltd. India.
Dwivedi, A.P. 1992. Agroforestry: Principles and Practices. Oxfood and IBH Publishing Co. Pvt. Ltd.
India.
Prakash, Ram. 1991. Propagation Practices of Improtant Indian Trees. International Book Distributions,
India.
Singh, S.P. 1998. HandBook of Agroforestry.Agrotech Publishing Academy, India.
Thapa, F. 2001. Nepalese Flora for Agroforestry Systems.S.B. Bhandari Publication, Nepal.
LECT 1 & 2: Concept of Agro forestry: Definition, importance and scope.

INTRODUCTION, CONCEPTS, DEFINITION, IMPORTANCE AND SCOPE OF

AGROFORESTRY

INTRODUCTION
Agro forestry, which involves integrating woody perennials in a farming system, has been a
longstanding practice of Nepal (Gilmour and Nurse, 1991). Trees are integral to hill farming and
have tangible impact on rural farming systems. A great diversity of tree species, often exceeding 100
species, exists in upland farms; they are scattered in and around homesteads. These trees contribute
substantially to carbon stocks in the system and carbon sequestration. It is important to understand
agro forestry systems and their role in carbon sequestration to formulate future strategies for
national-level carbon trading and natural resource management.
The major agro forestry practices in the hills of the eastern Himalayas include home gardens, agri-
silviculture system (planting trees along terrace bunds, borders and slopes), silvi-pastoral system
(livestock grazing in grasslands), agri-silvi-pastoral system (typical hill farming method, in which
crops are grown on flat terraces, trees on terrace bunds and borders, and grasses on terrace slopes;
and livestock are allowed to graze during fallow season), and alley cropping, agri-silviculture
system, silvi-pastoral system, horti-silvi-culture system and aqua-silviculture. Shifting cultivation
(also called slash and burn agriculture), though in decline, is still practiced in many upland areas in
the region.
Agro forestry has been recognized as a land-use system which is capable of yielding both wood and
food at the same time conserving and rehabilitating the ecosystems. It increases the productivity and
at the same time maintains the nutrient balance and as well as protect the nature. It has two major
roles, the productive role and the service role. Demographic pressure, demands the food, fodder, fuel,
medicines, timbers, vegetables etc. Role of Agro forestry for efficient nutrient utilization (cycling),
nitrogen fixation, organic matter addition and for improving drainage.
Latest forest resource assessment data reveal that out of the total land area of Nepal, forest including
other wooded land comprises around 5.96 million hectares (44.74 %), 1.56 million hectares (12%) of
grassland, 3.0 million (21%) of the farmland, about 1.06 million hectares (7%) of uncultivated
inclusion. The data shows that the forest areas have increased nearly by 5.14 percent. (Table 1)

Table 1: Land use of Nepal.

Categories Area (Million hectares) Percent
Forest*. 5.96 40.36
Other Wooded Land* 0.64 4.38
Grass land** 1.77 12.0
Agriculture land ** 3.09 21.0
0Non-cultivated inclusions** 1.03 7.0
Water, streams, and river beds** 0.38 2.6
Urban and industrial areas** 2.62 17.8
Total 15.49 105.14
*Source: DFRS, 2016. ** Source: GoN/MoFSC, 2014.

Forest, range land, wetland, and agro-ecosystem are the major ecosystem groups of Nepal. A total of
118 ecosystems are found in Nepal. Of the five physiographic zones of the country, Middle
Mountain has the maximum number of ecosystems (Table 2).

Table 2: Number of ecosystems in Nepal

Physiographic Zone Ecosystems
Number %
Terai 12 10.2
Siwalik 14 11.9
Middle Mountains 53 44
High Mountains 38 32.2
Other 1 0.8
Total 118 100
Source: GoN/MoFSC, 2014

CONCEPT OF AGROFORESTRY

Agro forestry is an age old practice, and has long tradition of growing food crops, trees and animals
together for producing multiple ranges of products. In fact, trees in our ancient literature that planting
tree was being done by individuals on their own along with agriculture crops. Maharishi Kashyap,
classifies land into several categories and identifies areas which are suitable for planting trees: all
wet and dry lands and areas around houses, wells, tanks are specifically identified for tree planting.
Now a days, Peoples are no longer able to meet their requirements of firewood, fodder, timber,
bamboo, etc. from the forest. Due to shortage of wood the prices of these commodities are increased
manifold. Many forest based industries have been facing problems in supply of raw material. Than
farmers are started planting trees on their farm lands to meet these shortages along with agriculture
crop; thus from the concept of agro forestry it emerged out. The concept of agro forestry is to
combine both modern and traditional land use systems where trees are managed together with crops
or animal production.
Agro forestry is a land-use system in which trees or shrubs are grown in association with agricultural
crops, pastures or livestock. Such integration of trees and shrubs in the land-use system can be either
a spatial arrangement, e.g., trees growing in a field at the same time as the crop, or in a time
sequence, e.g., shrubs grown on a fallow for restoration of soil fertility.

AGROFORESTRY DEFINITIONS:
"An efficient and integrated land use management system by raising of certain agricultural crops,
forest tree species and or animals simultaneously or sequentially on the same unit of land with
appropriate management practices which result in overall increase in the production, under a
particular set of climatic and edaphic conditions and socio-economic status of local people."

Agro forestry is relatively new name of for set of old land use practices. Many definitions have been
proposed world-wide. However it has now become an accepted land use system. Some of the
definitions given by different workers are as follows:

Bene et al. (1977) defined "agro forestry as a sustainable management system for land that increases
overall production, combines agriculture crops, forest plants and tree crop and/or animals
simultaneously or sequentially and applies management practices that are compatible with the
cultural patterns of a local population".

King and Chandler (1978): ―Agro forestry is a sustainable land management system which increases
the overall yield of the land, combines the production of crops (including tree crops)
and forest plants and/or animals simultaneously or sequentially, on the same unit of land and
applies management practices that are compatible with the cultural practices of the local population".

The International Centre for Research in Agro forestry (ICRAF, also known as the World Agro
forestry Centre) suggests the following definition:
"Agro forestry is a collective name for land use systems and technologies, where woody perennials
(trees, shrubs, palm bamboos, etc.) are deliberately used in the same piece of land management units
as agriculture crops and animals in some form of spatial arrangement or temporal sequence. In agro
forestry systems, there are both ecological and economical interactions between the different
components (Lundgren and Raintree, 1982),

Some of the basic ideas emerging from the definition of AGROFORESTRY

 Agro forestry normally involves two or more species of plants (or plants and animals).
 An agro forestry system always has two or more outputs.
 The cycle of an agro forestry system always lasts more than one year.
 Even the simplest agro forestry system is more complex, ecologically and economically, than a
mono-cropping system.
 In other words, agro forestry is a system of combining trees with crops (such as food, fruit,
vegetables, fodder and forage) and/or livestock in a field at the same time or at different times.

Objectives of Agro forestry:

In all agro forestry land management there are two essential and related aims such as
 The AFS should conserve and improve the site
 Optimize the combined production of tress, agricultural crops and animal

Purpose of agro forestry

 To optimize overall production of food/fruits, woody crops and fodder and forage including livestock
per unit area. ƒ
 To provide support for conservation of soil, water and other resources. ƒ
 To improve local environment. ƒ
 To enhance the socioeconomic condition of the farmers. ƒ
 To improve the livelihoods of the farmers.

Attributes of Agro forestry:

There are three attributes which, theoretically, all agro forestry system possess, these are:
 Productivity: Most, if not all, agro forestry systems aim to maintain or increase production (of
preferred commodities as well as productivity (of the land). Agro forestry can improve productivity
in many different ways. These include: increased output of tree products, improved yields of
associated crops, reduction of cropping system inputs, and increased labor efficiency.
 Sustainability: By conserving the production potential of the resource base, mainly through the
beneficial effects of woody perennials on soils, agro forestry can achieve and indefinitely maintain
conservation and fertility goals
 Adoptability: The word ―adopt‖ here means ―accept‖ and it may be distinguished from another
commonly used word adapt, which implies ―modify‖ or ―change.‖ The fact that agro forestry is a
relatively new word for an old set of practices means that, in some cases, agro forestry was already
been accepted by the farming community. However, the implication here is that improved or new
agro forestry technologies that are introduced into new areas should also conform to local farming
practices.

Table 3: Distinction between Social Forestry and Agro forestry

Social Forestry Agro forestry

1. Social forestry is a plantation for the benefit 1. Agro forestry is a sustainable land
of rural and urban communities, with objectives management system that increases the overall
to supply fuel wood to divert cow dung from production, combines agricultural crops, tree
village hearths to village fields, small timber for crops and forest plants and/or animals
housing and agricultural implements and fodder simultaneously or sequentially, and
for cattle of the rural population, protection of applies management practices that are
agriculture by creation of diverse ecosystem and compatible with the cultural patterns of the
arresting wind and water erosion, provide raw local population.
material for village cottage industries and
improve scenic value in rural and urban areas.
 2. It is thus the forestry of the people, by the 2. It is a system which is for managing the unit
people and for the people. of land for maximizes production of agricultural
crop and forest trees complimentary with each
other.

3. Planting of trees on massive scale is done on 3. Agro forestry is practiced mostly in farmers‘
vacant land, community land, roadside railway field/own land.
track and even degraded reserve forest. Helps to
eradicate poverty especially among land less
and marginal rural people by providing them job
potential.

4. Mainly trees and shrubs are to be used to 4. It involves integration of two or more than
harvest multiple products. two components ion the same unit of land.

5. It is primarily a government based 5. Agro forestry involves the rural awakening

programmed that aims to increase the forest area towards self sufficiency by producing
by rehabilitating wastelands while producing maximum biomass per unit area, fulfilling then
biomass both for industrial and local uses. needs of food, fodder and fuel wood etc..

Historical Background
 It is believed that Homo erectus used wood for fire at least 750,000 years ago.
 The oldest evidence of the use of wood for construction, found at the Kalambo Falls site in Tanzania,
dates from some 60,000 years ago.
 Carpenters and shipwrights fabricated wooden boats as early as 2700 BCE.
 The National School of Forestry was established in Nancy, France, in 1825.
 At the end of 19th century, forest plantation has been established adopting agro forestry systems,
which is known as Taungya agro forestry system.
 This system was first started from Burma in 1850s, where teak (Tectona grandis) plantation areas
were given to shifting cultivators to grow agriculture crops.
 Taungya agro forestry has been adopted widely in South Asia in 1890s.
 In present Bengladesh, plantation was established adopting Taungya approach in between 1887 to
1890s, where as this in West Bengal of India in 1896.
 Agro forestry was formally outlined in the early 20th century by American economic geographer J.
Russell Smith in his book Tree Crops: A Permanent Agriculture (1929). Smith viewed tree-based
―permanent agriculture‖ as a solution to the destructive erosion that often followed the cultivation of
sloping lands.
 However, his contributions were largely overlooked during the green revolution of the 1960s and the
subsequent and more-inclusive farming systems research/extension (FSR/E) development approach
of the early 1970s that sought sustainable agricultural alternatives.
 In 1977 the Canadian International Development Research Centre released a report called Trees,
Food and People (part of the Project for Identification of Tropical Forestry Research Priorities)
describing the critical role of trees in sustaining agricultural production in the tropics.
 That led to the establishment of the International Council for Research in Agro forestry (ICRAF),
ultimately headquartered in Nairobi, Kenya, in 1977, and in 1982 ICRAF launched the journal Agro
forestry Systems to provide a global research outlet for the newly emerging field. In 2002 ICRAF
was renamed the World Agro forestry Centre to reflect its global mandate.

In Nepal,
 Agro forestry practices in Nepal are traditional, very old, and very specific to the local social,
economic and agro ecological conditions. The farmers, grazers, and forest dwellers have an intimate
knowledge of these traditional practices.
 Agro forestry is a method of farming that allows trees and shrubs to grow along with crops and/or
livestock, therefore blending agriculture and forestry in the same production system. It is a traditional
practice, where fodder, fire wood and timber species are grown along terrace bunds, borders and
slopes.
 Shifting cultivation is also found commonly in Nepal until now.
Taungya agro forestry practice was first started in Nepal in 1972 in Tamagadhi of Bara district,
where forest areas encroached by the hill migrants were planted and given to encroachers to grow
agriculture. The main aim of this practice was to protect remaining forests from encroachment.
 After that Terai Community Forestry Development Project and Sagarnath Forestry Development
Project have also practiced this system in large scale from 1983 to 1992. These projects have given
plantation areas (generally 1 ha for one family) for poor farmers living around for 4-5 years on
simple agreement to grow agriculture crops without any damage to trees. Farmers were responsible
to replant seedlings when planted trees were damaged during growing crops in Taungya plots.
Traditional agro forestry farming system of Nepal includes growing of trees, agriculture crops and
livestock for the purpose of subsistence livelihood, which is gradually replaced by the cash crops.
 Farmers have started cultivating cash crops such as cardamom under Uttis (Alnus nepalensis), ginger
and turmeric under tree shade and home gardens, and coffee under Ipil Ipil (Leucaena leucocephala)
and shade trees, and tea under Sissoo (Dalbergia sissoo) and Siris (Albezzia spp), vegetables, and
fruits (orange, banana, papaya, mango, apple etc) for commercial purposes. These changes in crops
and cropping pattern have changed the agricultural landscape and environment resulting to
agricultural evolution.
Nepal Agricultural Research Council (NARC), Department of Forest Research and Survey (DFRS),
Nepal Agro forestry Foundation (NAF)/ Kathmandu Forestry College (KAFCOL), Institute of
Forestry (IOF) and other I/NGOs are promoting agro forestry research and extension work in Nepal.

IMPORTANCE OF AGROFORESTRY
1. It can help to increase food production and boost food security. Generally, trees can provide
nutritious fruits, nuts, and leaves for consumption in households and helps to improve the health and
nutrition status of people.
2. Felled trees and their residues can be used as wood energy for cooking and heating while leaves can
be used as forage for livestock.
3. It also supports the production of a wide range of products such as timber, fiber, fodder and forage,
craft products, medicinal products, hedging materials, and gums and resins among others.
4. Trees can block strong winds, protecting crops from damage. Some crops like barley, alfalfa, and
winter wheat are also known to thrive under shelter.
5. Trees also protect animals from wind chill in cold days while also providing shade on hot days and
thus, helping lower animal stress.
6. Trees can also be a source of medicines and natural remedies.
7. Agro forestry helps to reduce the vulnerabilities associated with agricultural production and even
improve the recovery after natural disasters, hazards, or socioeconomic downturns and reducing the
risk of economic failure.
8. Agro forestry can strengthen the soil structure; mitigating soil erosions, improving soil fertility, and
preventing possible landslides.
9. Agro forestry can bring forth sustained employment and higher income, which leads to an
improvement in rural living standards.
10. Growing trees in agricultural systems can reduce the impact of climate change on agriculture.
11. The roots of trees can strengthen the soil structure; mitigating soil erosions, improving soil
fertility, and preventing erosion, and landslides.
12. Agro forestry can help protect the natural resources in the environment. For example, growing trees
can help improve the quality of water and its quantity by filtering and capturing of water resources.
13. Trees also support biodiversity by providing a suitable environment for insects, animals, and plants.
14. Agro forestry improve environment: Plants absorb CO2 and supply O2 in the process of
photosynthesis, reduce pollutants from soil and water, reduce sound pollution, reduced pollution and
make clean environments.
15. Agro forestry creates aesthetic value or ornamental value, protect humankind‘s agricultural heritage
16. Agro forestry systems help in the reduction in incidences of total crop failure, which is common in
monoculture and single cropping systems.

Carbon Sequestration By trees

Understanding the carbon cycle on our planet is crucial to combat our climate crisis. In our gardens,
and on our farms, we can make choices that increase the rate of carbon sequestration over land. By
increasing carbon sequestration in plants and soil, we can work to regain balance in our planet's
carbon cycle. Carbon-conscious gardening and carbon farming are crucial tools in climate change
mitigation.
Carbon is present in the atmosphere, in the ground, in oceans and in living organic materials. It is
exchanged between these different reservoirs through a wide range of natural processes. Without
human interference, the natural flow of carbon would keep levels reasonably stable, and the carbon
cycle would remain in harmonious balance. According to the Salk Institute, every year plants and
other photosynthetic life capture 746 gigatons of CO2 and then release 727 gigatons of CO2 back.
Unfortunately, human activity has dramatically increased the amounts of carbon (approximately 37
gigatons) that is released into the atmosphere annually. This imbalance in the carbon cycle is one of
the main contributing factors to the greenhouse effect and global warming.

We can help to redress the balance by:

 Choosing the right plants – to sequester as much carbon as possible, for as long as possible.
 Caring for the soil to boost its carbon capture capability.
 Protecting and restoring existing carbon sink ecosystems around the globe
Most people are aware that planting trees is a good thing in climate change mitigation efforts. Trees
take carbon from the air through the process of photosynthesis and store it as lignin in their trunks,
roots and branches. This means that trees are able to turn CO2, from the atmosphere, into a very
stable form of elemental carbon.
Determining how much carbon an individual tree can sequester each year, and over its lifetime, is a
complex business. Carbon sequestration rates are influenced by the species of tree, its size and age,
temperatures and many other environmental factors. Even the best figures are only estimations, and it
is difficult to get accurate figures. These figures are always extremely variable and will be accurate
only for the very specific area where they were taken.
Generally speaking; however, all trees have an astonishing capacity to store carbon while in growth.
Research has shown that all tree species absorb CO2 from planting to old age (200 years plus).
However, they reach their peak in terms of carbon sequestration in their 'teenage' years (from 10-45
years after planting).

SCOPE OF AGROFORESTRY

There is tremendous scope for Agro forestry because more focused on the ecological problems and
shortage of fuel, fodder and other outputs as well as unemployment. Agro forestry has vast scope in
meeting this requirement through multipurpose tree species as:
(I) Large area is available in the form of farm boundaries, bunds, waste lands where this system can
be adopted
(II) This system permits the growing suitable tree species in the field where most annual crops are
growing well
(III) By growing trees and crops on Agricultural or forest land, Resources are utilized efficiently
(IV) System has potential generate employment.
(V) Provides raw material for the cottage industries
(VI) Helps in maintaining ecological balance
(VII) Soil and water conservation, soil improvement.
(VIII) Helps in meeting various needs of growing population
(IX) Solve the problem of acute shortage of fodder, fuel and other products along with fruits, shade
and protection

PROBLEMS, CHALLENGES AND OPPORTUNITIES

1. Problems and challenges of agroforestry development in terai and mid-hills

 Given the diverse uses, the day-to-day farming issues are far more complex than in a straight
forward forestry operation or monoculture farm.
 It is difficult to use farm machines in the confined space of agro-forests.
 Food crops may be damaged during the harvest of tree products.
 Trees might serve as hosts to diseases, insects, birds and small animals.
 Rapid regeneration of aggressive trees may displace food crops and take over entire fields.
 Agroforestry is more labor intensive than plantation of single crops. There is shortage of
farm-workers because of migration of villagers to urban and foreign countries for better job
opportunities and services.
 In most of the terai region, farmers are planted of trees only rather than agroforestry practices
because of shortage of farm worker, shortage of water, lack of technical knowledge.
 Growing agriculture and forest crops needs the understanding of silviculture and management
aspects of the trees and crops. The technical knowhow of the farmers are limited
 Farmers have poor knowledge on agroforestry systems and lack of appropriate nursery, seed
of improved species, and appropriate management systems. So the concerned organization
needs to disseminate information and technical understanding to the farmers for better returns
from the field. Agriculture crops are the first priority of the farmers and they have fear of
casting shade by the trees and hamper the growth of the crops. In such dilemmas, technical
support from concerned authorities is being lacked.
 Good quality and vigor seedlings of forest and horticulture crops are not easily available. If
they are available, it is difficult to assure of their quality. Farmers were concerned about the
easy availability and certified seedlings of their interest.
 Species combination plays important role to enhance the production and protection capacity
of the agroforestry farm. The study found that appropriate species combinations are mostly
overlooked. Eg. the species that shade leaves during agricultural period and that flourish
green leaves during the winter fodder deficit season when farmers are in need of fodder trees
to feed their livestock.
 Many agroforestry practices especially tea, coffee, and cardamom based are shifting from
subsistence to commercial based practices in western and eastern part of Nepal. In the same
time, farmers were concerned about the marketing of these products.
 There is lack of two way market linkages and buy back guarantee of the agroforestry
products which discourage the farmers to continue the practices in the long run.
 Value added tax imposed to the forestry crops have also discouraging and bringing frustration
among the farmers.
 Return on investment from planting trees takes many years and it is long term investment
with risk of failure from environmental, social and technical reasons.
 Risk of insect and pest infestation may destroy the trees and crops.
 Most of the farmers especially in mid hills have very small land holding size which limits the
adoption of agroforestry practices to subsistence farming practice only.

2. Opportunities of Agroforestry development in terai and mid hills

There are tremendous opportunities for agroforestry development and scaling up the system in mid-
hills and terai region of Nepal.

 Agroforestry is more profitable than forestry alone, and may have several climatic and social
advantages for the farmers as well as for the local and national prosperity. To create clean
 environment for promotion and to widen the opportunity of agroforestry in mid-hills and terai
region of the country.
 It has a tremendous opportunity to integrate agricultural, forest and horticultural crop in other
wooded land.
 Proper utilization of fallow farmlands and marginal lands. So, so it has a great opportunity to
extend the commercial and systematic agroforestry in those lands contributing to the income
and livelihood of millions of people together with an opportunity of employment and
minimized the migration.
 Every year, many terai and hill farms are converted into degraded land due to natural hazards
such as landslides, erosion, flooding, river course change, etc. In such land area, agroforestry
can be developed as rehabilitation measures and greening the hills and plains and can be
means of rural development as trees and crops can be managed simultaneously and guarantee
the sustainability of the system along with its contribution in household livelihoods.
 Agroforestry is a biodiversity-friendly land-use system that plays a strategy for wildlife
corridors and connectivity development.
 Agroforestry crops help in carbon sequestration and provide multiple benefits to the farmers.
Thus, it has a great potential to contribute to climate change mitigation and manage
ecosystem.

Needs of Agro forestry System

The different aspects in which agro forestry hold viable potentials to meet the demands of ever-
growing human and livestock population are as follows:

i) Fulfill the demand of food, fuel wood & fodder

 Enhanced food production of crops associated with trees through nitrogen fixation, better access to
soil nutrients due to high cation-exchange capacity of the soil and its organic matter and mycorrhizal
associations
 Fulfill the needs of food for man from trees as fruits, nuts and cereal substitutes
 Good source of Fodder for animals and good shelter of birds.
ii) Water conservation
 Improvement of soil-moisture retention in rain fed croplands and pastures.
 Reducing flood hazards and a more even supply of water through reduction of run-off.
 Improvement in drainage from waterlogged or saline soils by trees with high water requirements.
iii) Fuel wood and energy
 Provide Fuel-wood for cooking and direct combustion
 Pyrolytic conversion products such as charcoal. oil and gas
 Extraction of Oils, latex and other combustible saps and resins
iv) Shelter from trees
 It provides the Building materials for shelter, construction and furniture's
 Shade trees for people, livestock and shade-loving crops
 Wind-breaks and shelter-belts for protection of settlements, crop lands, pastures and roadways
 Fencing: live fences and fence posts
v) Raw material for industries
 Provides Raw material for pulp and paper industry
 Tannins, essential oils and medicinal ingredients
 Wood for agricultural implements and various crafts
 Fibre for weaving
vi) Cash benefits
 Direct cash benefits from sale of tree products
 More income per unit of land than monoculture
vii) Increased yield and maximized production:
Combining agriculture crops with trees helps in increasing the productivity of the land by:
 Many leguminous tree species fix nitrogen from the atmosphere and return much more in leaf fall
than they take from soil.
 Leaves of tree species could be used as green manure and help the farmer to increase soil
productivity at optimum levels over a long period of time.
viii) Diversified products:
 Several trees, shrubs, herbs and climbers yield a substantial quantity of food materials which are
used by rural poor and particularly by tribal.
 About 213 species of large and small trees, 17 species of palm, 128 species of shrubs, 116 species of
herbs, 4 species of fern and 15 species of fungi are known to yield edible/food material.
 Thus, by adopting agro forestry one can get diversified products viz. fuel, fodder, fruits, fibre,
timber, etc.
 Tree and agriculture crop production system is more productive and is capable of meeting almost all
the demands of timber, fodder, fruits, fiber and firewood.
ix) Utilization of wasteland and degraded land:
 West and degraded lands are utilized properly by the cultivation of trees.
x) Employment opportunities:
 Agro forestry systems increase the employment opportunities.
 Wood based industries such as saw milling, furniture, sports goods, pulp and paper; Match splints,
bamboo and cane furniture, etc. are the important sectors where rural youth get employment.
xi) Carbon sequestration services and its influence on climate change:
 One of the most important contributions of agro forestry in general is to respond to climate change
through sequestration of carbon in above ground plant biomass and below ground biomass in the
soils.
xii) Potential reduction in the rate of deforestation:
 Agro forestry reduced the annual rate of deforestation to a great extent.
 The time that household/family members especially women would have spent walking long distances
in search of fuel wood in forests can be saved.
xiii) Improved soil health
 Trees improve physico-chemical properties of soil.
 The trees biomass also provide favorable environment for soil microbes and fauna which in turn
break down the biomass and release plant nutrients.
xiv) Agro forestry as a habitat for wild species
 Agro forestry can enhance connectivity and landscape heterogeneity in multi-functional conservation
landscape.

Assignments:
1. Define agro forestry it's important, scope and limitation of agro forestry in Nepal, suggest how
can improve limitation.

LECT- 3 & 4: TREE SELECTION AND IMPROVEMENTS

SELECTION OF TREE CROP SPECIES FOR AGROFRESTRY

Agro forestry is a deliberate integration of trees and crops in general, in same unit of land. These
trees and crops compete with each other for nutrients, moisture and light. Among different
components one must select a compatible component so that from a single unit of land a
farmer/cultivator maximize his production. While selecting tree species for agro forestry there are
three factors must taken into consideration.

1. CLIMATE
2. SOIL
3. BIOTIC FACTOR

1. CLIMATE:-
 The forest of Nepal has been described here on the basis of the levels of altitude, and different types
of climate under the following vegetation zones:
1. Tropical zone(-1,000m):
This zone principally includes Terai, Bhabar, and Dun valleys. It extends from east to west up to
1,000m and major vegetation types are Sal forest, Tropical deciduous riverine forest and Tropical
evergreen forest. The common tree associates are Terminalia belliraca, T. chebula, Dillenia
pentagyna, Butea monosperma, Mimosarubbicaulis, M. pudica.

2. Subtropical zone (1,000-2,000m):

This zone prevails to an elevation of 1,000-2,000m. It comprises the outer foothills, lower parts of
Mahabharat range, midland areas and Himalayas. Schima- Castanopsis, Pinus roxburghii and Alnus
nepalensis are the important forest types. The associated tree species are Engelhardia spicata, Acer
oblungum, Michelia kisopa, Persea odoratissimia, Litsea doshia, Ficus nerrifolius, F. auriculate,
etc.
3. Temperate zone (2,000-3,000m):
It runs almost parallel and north to outer foothills from east to west and includes mainly the
Mahabharat range and the southern sides of the main Himalayan ranges.
The region falls at an altitude of 2,000-3,000 m and is characterized by lower temperate mixed
broad-leaved forest, temperate mixed evergreen forest, and upper temperate mixed broad-leaved
forest. The forest is evergreen majorly composed of laurels such as Persia duthiei, P. odoratissima,
P. pallida, Neolitsea pallens, Quercus lamellose, Q. glauca, Q. semecarpifolia etc. etc.

4. Subalpine zone (3,000-4,100m):

It covers the part of the greater Himalayas between 3,000-4,100m. It is characterized by Silver fir
and Birch-Rhododendron forests. In the west region, the birch occurs mixed with fir and oak. In the
inner valleys it occurs with Juniperus recurve, Prunus cornuta, and shrubs, climbers and herbs
are Lonicera myrtillus, Cortoneaster acuminatus, Campanula latifolia, Inula roylena, Rhodiola
himalensis etc.
5. Alpine zone (4,100-5,500m):
This zone above 4,100m comprises the association of Juniper-Rhododendron-Caragana- Lonicera,
and alpine meadows. In the heads of Inner valleys between 4,000-4,300m, Juniper-Rhododendron
association includes Juniperus spp (J. recurva, J. indica, J. indica) and Rhododendron spp. (R.
anthopogon, R. lepidotum) on exposed slopes.
The other associated species are Lonicera myrtillus, L. obovata, Ephedra gerardiana, Spiraea
arcuate, etc.
Some of the striking and ornamental plants in this belt are Anemone obtusiloba, Campanula aristate,
Corydalis meifolia, C. ramosa, Delphinium brunonianum, D. vestitum, Gentiana depressa, G.
prolata, G. venusta, Maharanga emodi, Mecanopsis dhwojii, M. horridula, M. simplicifolia, Primula
calderana, P. sikkimensis, P. tibetica etc.

2. SOIL:- TREE SPECIES SELECTED FOR AGROFORESTRY TAKING INTO ACCOUNT

SOIL TYPE
Desert soil: Prosopis cineraria, P. chilensis, Acacia tortilis, A. senegal, A. nilotica, Salvadora spp
Recent alluvium: Acacia catechu, Dalbergia sissoo, Bombax ceiba etc.

Old alluvium:
Saline-alkali soils: Prosopis spp, Acacia nilotica, Azadirachta indica, Ailanthus spp, Eucalyptus spp,
Tamarix spp, Pongamia pinnata
Coastal and deltaic alluvium: Casuarina equisetifolia, Cocus nucifera, Areca catechu, Avicennia
spp
Red soils: Tectona grandis, Madhuca indica, Mangifera indica, Dalbergia sissoo, Acacia nilotica,
Leucaena leucocephala, Azadirachta indica, Eucalyptus hybrid, Pterocarpus marsupium, Adina
cardifolia, Dendrocalamus strictus
Black cotton soils: Acacia nilotica, A leucophloea, Tectona grandis, Hardwickia binnata, Adina
 cardifolia, Tamarandius indica, Aegle marmelos, Bauhinia spp, Dalbergia latifolia
Laterite and lateric soils: Tectona grndis, Eucalyptus spp, Acacia auriculiformis, Azadirachta
indica, Tamarindus indica, Emblica officinalis
Peaty and organic soil: Syzygium cuminii, Ficus glomerata, Bischofia javanica, Lagerstromia
speciosa, Glircidia sepium
Hill soils: Juglans regia, Alnus nitida, Toona serrata, Cedrus deodra, Quercus spp, Grewia optiva,
Celtis australis

3. BIOTIC FACTORS:- Choice of species is also governed by biotic factors such as grazing, fire
and incidence of Insect pest etc.

A. THE ROLE OF TREES IN LAND USE AND PEOPLES NEEDS

1. Trees for Products and services derived like food (arable crops, vegetables, honey, pollen, animal
products, fruiuts, mushroom oils, nuts and leaves), shelter, energy, medicine, cash income, raw
materials for crafts, fodder and forage and resources.
2. Trees for Food and nutrition eg. variety of fruits and other edible products
3. Trees for shelter and other structures eg. timber and poles
4. Trees for medicine eg. variety of species of trees and shrubs, as well as herbs,
5. Trees for cash, savings and investment Eg. Products sold for cash are fruits, timber and poles
6. Trees can help in conservation of soil and water, enhance soil fertility and improve soil structure.
7. Trees for livestock and beekeeping
8. Trees for maintained environment
9. Trees for latex (Rubber from Haveabrassilensis) , gum and resins , Fiber, pulp for paper, tannin, lac
production
10. For Thatching and hedging materials, Gardening materials like stick, stacking materials, poles,
fencing materials, handle of tools etc.
11. For Crafts product from Albizia, Somtalum, Tictona, Gmelinasp., Dallarmasjy.
12. Recreation agro-tourism, sport, hunting etc.
13. Ecological and socioeconomic services

Important of trees

1) Trees are the main source of Oxygen.

2) An average tree produces enough oxygen to fulfill the oxygen need of four people.
3) Trees help in absorbing dust and other pollutants from the air, thus cleaning it.
4) The land under the tree absorbs more rainwater and helps prevent floods.
5) Trees also absorb a considerable amount of sound and help reducing noise pollution.
6) Birds lay their eggs in the nests on the tree, thus trees also help in nurturing many species.
7) Many trees also have medicinal properties and are used in healthcare industries.
8) They also save us from the harmful Ultra Violet rays, which is responsible for skin cancer.
9) Trees are also important for many industries, like Timber, Paper, Rubber, Silk etc., helping in
economic development.
10) From roots to leaves, every part of a tree is beneficial to us.
 Common uses of Trees in an Agro forestry system
1. Trees in home garden, path, roadside, public places
2. Trees in crop land and pastures
3. Trees in alley cropping
4. Trees in contour line and water ways
5. Living fence, borderline planting and boundary planting
6. Trees for wind break and shelter belts
7. Trees on earth works or soil conservation
8. Woodlot production
9. Protein bank for livestock

Potential Tree species for Agro forestry System

1. Timber tree species:–
Teak (Tectonagrandis) –Poumoli (Flueggeaflexuosa) –Caribbean Pine (Pinuscaribaea–Mahogany
(Swieteniamacrophylla)–Terminalia cattappa–Pandanusspp.
2. Trees that provide food, fruits & nuts
Coconut (Cocusnucifera)-Breadfruit (Artocarpusaltiles)-Coffee ( Coffeaarabica)-Cocoa
(Theobromacacao)-Ngalenut (Canariumindicum)-Mango (Mangiferaindica)-Avocado ( Persia
americana)-Papaya (Caricapapaya)-Citrus spp.Supply andexchangeof improvedplantingmaterial
3. Tree species for essential oil:
-Sandal wood (Santalumspp.)-Coconut (Cocusnucifera)- Dilo(Calophylluminophyllum)-Mokosoi
(Canangaodorata)- Agar wood (Aquilariaspp.) Masala (Ecalaptus spc.)
4. Multipurpose Trees:-
Gliricidiasepieum-Azadirachtaindica-MoringaOleifera-Morindacitrifolia

Suitable Species for Firewood/Fuel wood/ Energy Plantation for different regions
1. Tropical dry region: Acacia catechu, Acacia modesta, Acacia nilotica, Acacia Senegal, Acacia
tortilis, Anogeissus pendula, Albizia lebbek, Azadirachta indica, Cassia siamea, Cordia
rothii, Dalbergia sissoo, Emblica officinalis, Eucalyptus camaldulensis, Erythrina superb, Gmelina
arborea, Parkinsonia aculeate, Peltophorum ferrugineum, Pongamia pinnata, Prosopis cineraria,
Prosopis juliflora, Tamarindus indica, Tamarix troupe, Tecomella undulate, Zizyphus maurtiana etc.
2. Tropical humid region: Adina cordifolia, Acacia auriculiformis, Acacia catechu, Acacia nilotica,
Albizia procera, Azadirachta indica, Cassia siamea, Casuarina equisetifolia, Dalbergia sissoo,
Dendrocalamus strictus, Ficus spp., Eucalyptus spp., Kydia calycina, Leucaena leucocephala,
Madhuca indica, Melia azedarach, Morus alba, Salix tetrasperma, Syzygium cuminii, Tamarindus
indica, Trewia nudiflora, Gliricidia sepium and Gmelina arborea.
3. Sub-tropical region: Acacia catechu, Acacia melanoxylon, Acacia nilotica, Aesculus indica,
Ailanthus excels, Celtis australis, Grevillea robusta, Michelia champaca, Populus deltoids, Populus
nigra, Robinia pseudoacacia, Salix alba and Toona ciliate.
4. Temperate climate: Acer spp., Aesculus indica, Alnus nepalensis, Alnus nitida, Celtis australis,
Populus ciliate, Quercus semecarpifolia, Salix alba and Toona serrata

DESIRABLE CHARACTERISTICS OF TREES FOR AGROFORESTRY SYSTEMS

While selecting tree species for agro forestry systems, the following desirable characteristics should
be taken into consideration.
1. Minimum interference with crops with respect to soil moisture, nutrients and sunlight.
2. Adequate shade regulation and upright stems.
3. Easy establishment and good survival rate.
4. Fast growing habit such as Poplar, Casuriana, Leucaena leucocephala etc. are important species
which provide lot of opportunities to be planted in AFS and easy management.
5. Fixes atmospheric nitrogen.
6. High re-sprouting capacity after lopping, coppicing, pollarding and pruning.
7. Deep root system with very few lateral roots
 8. No toxic effects on soil and on associated crop plants
9. Multiple products like fuel wood, leaf fodder, edible fruit, edible flower and fibre
10. Suitable for local climatic conditions
11. Acceptable to local farmers and wider adaptability
12. Easily palatable and digestible for livestock
13. Shelter conferring and soil stabilization attributes Eg. Poplars (Populus spp.), Willows (Salix spp.),
Casurina equisetifolia, etc. have been extensively used in soil erosion control because of their
extensive root system and ability to grow in water-logged soils.
14. Nutrient cycling and nitrogen fixation attributes
15. Easily decomposable leaves, small in size, decompose quickly and easily, and add a large quantity of
organic matter and nutrients to the soil
16. Free from chemical exudations like allelo-chemicals affect the growth of under-ground crops.

CHARACTERISTICS OF AGRICULTURAL CROPS FOR AGROFORESTRY

a) Agricultural crops should be short duration and quick growing.
b) They should be at least partially tolerant to shade.
c) Most of them should belong to Leguminosae family.
d) They should respond well to high density tree planting.
e) They should bear some adverse conditions, like water stress and/or excess of watering;
f) Crops should return adequate organic matter to soil through their fallen leaves, root system,
stumps, etc.
g) Crops should appropriately be fitted in intensive or multiple cropping system.

Assignments:
1. Highlight the characteristics of trees which are used in agro forestry system.
2. Listing the trees at list five commonly uses for agro forestry system in Nepal with climatic zone,
botanical name and family. Trees used in home garden, path, roadside, public places, soil
conservation, fence, boundary, fodder, fruits vegetables, wine break, shelter/ construction, furniture,
medicinal, ornamentals, fuel wood, erosion control, nitrogen fixing etc.

LECT- 5 & 6

AGROFORESTRY SYSTEM (AFS)

Classification of Agro forestry System

According to. Nair (1987), agro forestry systems can be classified in to the following basis/sets of
criteria:
A. Structural basis: Considering the composition of the components, including spatial admixture of the
woody component, vertical stratification of the component mix arid temporal arrangement of the
different components.
B. Functional basis: This is based on the major function or role of the different components of the
system, mainly of the woody components (these can be product, e.g., production of food, fodder, fuel
wood and so on or protective, e.g., windbreak, shelter-belts, soil conservation and so on).
C. Socioeconomic basis: Considers the level of inputs of management (low input, high input) or
intensity or scale of management and commercial goals (subsistence, commercial, intermediate).
D. Ecological basis: Takes into account the environmental conditions on the assumption that certain
types of systems can be more appropriate for certain ecological conditions. There may be a set of AF
systems for arid and semi-arid lands etc.

A. Structural Basis of Classification

The structural of a system can be defined in terms of its components and the expected role or
function of each. In this system the type of component and their arrangement are important. Hence,
on the basis of structure, AF systems can be grouped into two categories:
1. Nature of components and
2. Arrangement of components.

1. Nature of Components :
Based on the nature of components, AF systems can be classified into the following categories;
a. Agrisilvicultural systems
b. Silvopastoral systems
c. Agrosilvopastoral systems and
d. Other systems.

a. Agrisilvicultural System (crops and trees + shrubs/vines and trees)

This system involves the conscious and deliberate use of land for the concurrent production of
agricultural crops including tree crops and forest crops.
Based on the nature of the components this system can be grouped into various forms.
1) Improved fallow system
When the fallow is enriched with fast-growing trees, shrubs or vines, the practice is called
"improved fallow." Improved fallow is an agro forestry practice that has its origins in slash-and-
burn agriculture. The trees and shrubs are left to occupy the site for several months or years. In this
system, planting a crop is done in the fallow lands at the end of shifting cultivation. This practice
decreases soil erosion in the subsequent years and recovers depleted soil nutrients.
2) The Taungya system
The ‗Taungya‘ is a Burrvege word consisting of ‗Taung‘ means hill and ‗ya‘ means cultivation i.e.
cultivation in the hill. Taungya was reported to have started first in Burma in the year 1850 and in
Java 1956. Taungya was introduced to India by Brandis in 1956. In Nepal, it was initiated in 1972 at
Tamagadhi area of Bara District. This area was originally covered with Sal and Asna their associates.
The forest area is highly encroached by the hill migrants. Therefore, the Taungya system was
introduced to save these forests.
Types of Taungya
i) Departmental Taungya
Agro crops are raised by the Department by employing labors and its main objective is to suppress
the growth of the unwanted vegetation and enhances tree growth.
ii) Leased Taungya
The plantation area is given to the farmers, who offer the highest amount of money for a specified
period of time.
iii) Free Taungya
Land is given to the farmers without charging money.
iv) Village Taungya
Of all the Taungya systems, it is the most successful system. People are allowed to settle as a village
inside the forested areas and land is given an area of 1 ha for raising agro-crops for 3-4 years.
Characteristics of Taungya
❖ Modified form of shifting cultivation.
❖ Crops are raised one year before the plantation.
❖ Crops and trees are raised simultaneously.
❖ Areas are abandoned after the canopy closes.
❖ Cycle is very short (3-4 years).
❖ After the completion of one cycle farmers have to move to another site if available.
Advantages
❖ It is obtained cheaply which reduces the cost of planting and maintenance.
❖ It solves the problem of unemployment.
❖ It helps maximum utilization of the site.
❖ It offers high reneumerization to the forest department.
❖ It has a provision for food crops in addition to forest trees.
❖ Weed and climber growth are effectively eliminated.
❖ There will be the multiple value such as timber, fodder, fuel wood, etc.
 Problems/disadvantages
 Farmers may cut the trees for the favor of crop growth.
 More crops per unit may deplete the soil fertility.
 Exposure of soil enhances the soil erosion.
 There may be danger of epidemic diseases and spread from food crops to forest trees.
 Legal problems arise on the land allocation and returning.
 It is the form of human labor exploitation.

3) Multispecies tree garden

In this system, mixture of various kinds of tree species are grown to provide multiple output such as
food, fodder and wood products.
4) Trees and shrubs on pasture
5) Alley cropping/Hedge row intercropping (given in previous model chapter)
6) Multi-purpose tree and shrubs
In this system, various multipurpose tree species are planted scatter or in some patterns. This system
produces multiple products and offers productive function too. The suitable trees are
Leucanaenaleucocephala, Acacia albida, Cassia sisamea, Casaurinaequisetifolia,
Azadirachtaindica, Acacia Senegal, Cocusnucifera etc.
7) Crop combination with plantation crops
In this, perennial trees and shrubs (coffee, tea, coconut) are combined in the intercropping systems
8) Agro forestry fuel-wood plantation
In this system, fuel wood species are inter-planted on or around agricultural lands. This system acts
both fence as well as shelter-belts besides proving fuel wood to local community. Suitable trees
species for this system are Acacia nilotica, Albizzialebbek, Cassia siamea, Casaurinaequisetifolia,
Dalbergiasissoo, Prosopisjuliflora, Eucalyptus terticornis etc.
9) Shelter belts
Shelter-belts are the belt of rows of trees established at right angle to the prevailing wind direction.
Shelter-belt deflects the air currents and thus by reduces the wind velocity and erosion. It provides
protection to the leeward areas against wind erosion and decreases the desiccation effects on plants.
It also provides food, fodder and timber.
Shelter-belts have a typical pyramidal shape. This is achieved by raising tall trees (a) in center and
medium sized (b) trees in adjacent to both side. Thereafter, shrubs (c) and grasses (d) are planted in a
similar fashion. Shelter-belt up to 50 meter width with suitable spacing is ideal. The ratio of the
height and width of shelter-belt should be roughly 1:10. Shelter-belts are oriented right angled to the
prevailing wind direction. Shelter-belts are raised in quadrangles (4 sided spatial) if the wind
direction to change very often. The minimum length of protection given by a shelter-belt is about 25
times its height.
The following species are recommended for shelter-belt establishment:
 Grasses: Saccharumspontanizem, S. munja, Panicumantidotale, Ceuchrus sp. Etc.
 Shrubs: Calotropisprocora, Clerodendronphlomoides, Cassia auriculata, Dodonaia viscose etc.
 Tree species: Acacia Arabica, A. leucopholea, Dalbergiasissoo, Eucalyptus spp. Tamarix articulate,
Parkinsonia aculeate, Prosopsisjuliflora, Casaurinaequisetifolia etc.
10) Wind breaks
Wind breaks refers to the strip of trees and/ or shrubs planted in order to protect fields, homes, canals
or other areas from wind and blowing soil. It protects the livestock from cold winds. Windbreak
protects crops and pastures form hot and drying winds. Windbreak reduces soil erosion and provides
habitat for wildlife. It reduces the evaporation from farmlands and improves the micro-climate. It
acts as a fence and boundary, it retards grass fire during summer season. In addition, wind break
provides useful products such as poles, fuel wood. Fruit, fodder, fiber and mulch.
Usually, in general, trees with narrow, vertical growth are ideal for wind break which includes
Eucalyptus, Cassia, Propis, Leucaena, Casaurina, Acacia, Grivillea, Syzygium and Dalbergia
species.

11) Soil conservation hedge

In this system, trees can be planted on soil conservation works such as bund and terraces. These
trees augment the conservation work through stabilization of soil. The interception of rain and
obstruction of wind reduces the soil erosion. Grevillearobusta, Acacia catechu, Pinusroxborghii,
Prosopoisjuliflora, Alnusnepalensis, Leucaenaleucocephala are used for this purpose ewith grasses.

12) Riparian Buffer

A riparian buffer or stream buffer is a vegetated area near a stream, usually forested, which helps
shade and partially protect the stream from the impact of adjacent land uses. It plays a key role in
increasing water quality in associated streams, rivers, and lakes, thus providing environmental
benefits.
 b. Agrosilvopastoral system (trees + crops+pasture/animals)
This system refers to the production of woody perennial along with annuals and pastures. This
system is grouped into two categories viz. home garden and woody hedge rows for browse, mulch,
green mulch and soil conservation.

I. Home Garden
This is one of the oldest agro forestry practices, found extensively in high rainfall areas in tropical
south and south-east Asia. Many species of trees, bushes, vegetables and other herbaceous plants are
grown in dense and apparently random arrangements, although some rational control over choice
plants and their spatial and temporal arrangement may be exercised. Most home gardens also support
a variety of animals (cow, buffalo, bullock, goat, sheep) and birds (chicken, duck). In some places
pigs are also raised. Fodder and legumes are widely grown to meet the daily fodder requirements of
cattle. The waste materials from crops and homes are used as fodder/feed for animals/birds and barn
wastes are used as manure for crops. Homestead occupies an area around 0.2-0.5 ha. This system is
managed by family members.
Home garden is also called as Multi-tier system or Multi-tier cropping as it consists of different
canopy strata. In this system, herbaceous plant constitutes the ground layer and trees occupy the top
storey. In the ground layer, vegetables grwon up to lm height whereas food crops such as banana,
papaya occupies layer of 1-3 m. The woody species occupies the top layer which includes
Atrocarpusheterophyllus, Citrus spp., Psidiumguajava, Mangiferaindica, Azadirachtaindica,
Cocusnucifera etc.

II. Woody Hedge rows

In this system various woody hedges especially fast-growing and coppicing fodder shrubs and trees,
are planted for the purpose of browse, mulch, green manure, soil conservation etc. The main aim of
this system is production of food/fodder/fuel wood and soil conservation. The suitable species for
this system are: Erythrium spp., Leucaenaleucocephala&Sesbaniagrandiflora etc.

c. Silvopastoral systems
Silvipasture refers to the production of woody plants in pasture land, the trees and shrubs mainly
provide fodder. The majority of rangeland grazing in hills is typically comprise the grazing of natural
herbaceous and shrubby vegetation for under trees such as pines, bhimal, Oak etc. This system is
again classified into three categories:. The three categories of this system are as follows:
I. Live fence of fodder trees and hedges
In this system, fodder trees and hedges are planted along the boundaries which serve as a live fence
in addition to providing fodder. The suitable species for this purpose are: Gliricidiasepizum,
Sesbaniagrandiflora, Erythrina spp. & Acacia spp.
II. Protein bank
In this system, protein rich fodder trees are planted in and around range and farrow lands so as to
augments the fodder quality and quantity in range lands. The suitable species are: Acacia nilotica,
Albizzialebbek, Azadirachtaindica, Leucaenaleucocephala, Gliricidiasepim, Sesbaniagrandiflora etc.
 III. Trees and shrubs on pastures
In this system, various trees and shrubs are scattered irregularly or arranged systematically which
supplements forage production. Acacia nilotica, Tamarindusindica, Azadirachtaindica etc. are used
for this purpose.

d. Other Systems

The following systems can be included:

I. Apiculture with Trees: In this system various honey (nectar) producing tree species frequently
visited by honeybees are planted on the boundary, mixed with an agricultural crop. The main
purpose of this system is the production of honey.
II. Aquaforestry: In this system various trees and shrubs preferred by fish are planted on the boundary
and around fish-ponds. Tree leaves are used as forage for fish. The main or primary role of this
system is fish production and bund stabilization around fish-ponds.
III. Multipurpose Wood Lots: In this system special location-specific MPTS are grown mixed or
separately planted for various purposes such as wood, fodder, soil protection, soil reclamation etc.

2. Arrangement of Components AF Systems

The arrangement of components gives first priority to the plants even in AF systems involving
animals. Their management according to a definite plan, say a rotational grazing scheme, gives
precedence to the plants over the animals. Such plant arrangements in multispecies combinations
involve the dimensions of space and time.
I. Spatial Arrangement - Spatial arrangements of plants in an AF mixture may result in dense mixed
stands (as in home gardens) or in sparse mix stands (as in most systems of trees in pastures). The
species (or species mixtures) may be laid out in zones or strips of varying widths. There may be
several forms of such zones, varying from microzonal arrangements (such as alternate rows) to
macrozonal ones.
II. Temporal Arrangement - Temporal arrangements of plants in AF may also take various forms. An
extreme example is the conventional shifting cultivation cycles involving 2-4 years of cropping and
more than 15 years of fallow cycle, when a selected woody species or mixtures of species may be
planted. Similarly, some silvopastoral systems may involve grass leys in rotation with some species
of grass remaining on the land for several years. These temporal arrangements of components in AF
are termed coincident, concomitant, overlapping (relay cropping), separate and interpolated.

Crop combinations with plantation crops:

Perennial trees and shrubs such as coffee, tea, coconut and cocoa are combined into intercropping
systems in numerous ways, including:
i. Integrated multistory mixture of plantation crops;
.immixture of plantation crops in alternate or other crop arrangement;
iii.Shade trees for plantation cropsiv.Intercropping with agricultural crops.
Tea (Camilia sinensis) is grown under shade of A. chinensis,A. odoratissim,A. lebbek,A. procera,
Acacia lenticularis,Derris robusta,Grevillea robusta, Acacia spp., Erythrina lithosperma, Indigofera
tesmanii.

a) Coffee (Coffea arabica) is grown under the shade of Erythrina lithosperma as temporary shade while,
permanent shade trees include Ficus glomerata, F. nervosa, Albizia chinensis, A. lebbek, A
moluccana, A. sumatrana, Dalbergia latifolia, Artocarpus integrifolius, Bischofia javanica, Grevillea
robusta.
b) Cacao (Theobroma cacao) is grown under the shade of coconut and areca nut,and Dipterocarpus
macrocarpa (in forest).
c) Black pepper (Piper nigrum) is grown with support from Erithrina indica, Garuga pinnata, Spondias,
Mangifera, Gliricidia maculate and Grevillea robusta.
 d) Small cardamom (Elettaria cardamomum) and large cardamom (Ammomum subulatum; A.
aromaticum) grow in forests under temporary shade tree of Mesopsis emini..
e) Large cardamom is grown under the shade of natural forest as well under planted shade treesviz.,
Alnus nepalensis, Schima wallichii; Cinchona spp.; Lagerstroemia spp., Albizia lebbek; Castanopsis
tribuloides; C. hystrix; C. indica; Terminalia myriocarpa; Bischofiajavanica.

Suitability of agro forestry system:

Condition/Area Agro forestry System
i. Humid tropical/ Subtropical Home garden, Trees on rangelands and pastures, Improved fallow in
lands shifting cultivation, Multipurpose woodlots.
ii. Semi-arid/arid lands Silvipastural system
iii.Tropical high lands Woody perennials for soil conservation, Improved fallow.

B. Functional basis Classification of Agro forestry Systems

Two fundamental attributes of all AF systems are productivity and sustainability. This clearly
indicates that AF systems have two functions.
Functions of agro forestry
1. Productive: Agro forestry can produce food crops, fruits, leaf litter, timber, fuel wood and fodder for
livestock from the same piece of land.
2. Protective: Agro forestry helps to minimize degradation of farmland and other natural resources
(e.g., wind break, shelter-belt, soil and moisture conservation and soil erosion).
3. Ameliorative: Agro forestry with legume trees and crops help to maintain or improve the
productivity of land.
4. Livelihood improvement: Income can be generated from sale of trees and agricultural products.

C. Socioeconomic basis Classification of Agro forestry Systems

Based on such socioeconomic criteria as scale of production and level of technology input and
management, agro forestry systems have been grouped into three categories:
1. Commercial,
2. Intermediate and
3. Subsistence systems

D. Ecological Grouping of Agro forestry Systems

Based on the major agro ecological zones, agro forestry systems are grouped into the following
categories:
I. Humid/sub-humid lowlands:
This region is characterized by hot humid climate for all or most of the year and evergreen or semi-
evergreen vegetation. The lowland humid and subhumid tropics (commonly referred to as the humid
tropics) are by far the most important ecological region in terms of the total human population. It
supports extent of area and diversity of agro forestry and other land-use systems. Because of climatic
conditions that favour rapid growth of a large number of plant species, various types of agro forestry
plant associations can be found in areas with a high human population, e.g., various forms of home
gardens, Plantation of crops with combinations and multilayer tree gardens, in areas of low
population density, trees on rangelands and pastures.
II. Semi-arid/arid lands:
This region is characterized by rainfalls confined to 9-21 days in July -Sept., 2-4 wet months, vapour
pressure deficit ranging from 9 mb in January to 30 mb in April May, solar radiation incidence (400-
500 cal/cm2/day), high wind velocity (20 km/hour), high potential evapotranspiration (6 mm/day)
and high mean aridity Index (70-74.8%).
III. Highlands:
Variable rainfall, degraded and shallow lands at high altitude to deep rich soils in valleys and great
climatic variations are the features of highlands. This area is a storehouse of great biological
diversity. The Himalayan region is an excellent example of this type of area. Agro forestry has long
encompassed many well-known land-use systems practices.
 Important Land use systems in Nepal / Different types of Agroforestrv models

1. Alley cropping/Hedge-row intercropping:

It is one of the promising models of agro forestry where arable crops are grown in the alleys between
the rows of woody perennials (AFS) and the trees are pruned periodically during the peak growing
season of the crop to prevent shading and to provide green manure or mulch to arable crops.
Currently a large number of organizations are involved in arraying out research activities on alley
cropping. IITA , Ibadan, Nigeria (1972) is the pioneering organization to evolve and popularize the
concept of alley cropping all over the world.

2. Boundary Planting:
It is one of the conventional agro forestry system where the trees are planted on the farm boundaries
to demarcate the boundaries.\

3. Strip Hedge-row Intercropping:

In this model strips of tree rows are altered with agro-crops.

4. Concentric Design:
In this model tress are sparsely planted on the ground and agro-crops are planted around the
periphery in a circular fashion. This design offers the advantages of studying the effect of orientation
(North, South, East& West) on productivity.

5. Contour Hedge rows intercropping:

In this model trees are planted on contour at a close spacing of 1 -2 m and pruned branches are left
 on the contour lines which provides a barrier to the flow of run-off. This model progressively
transforms sloping area into terraces.

6. Nelder-Wheel model:
This model was developed by an American forester. It is one of the efficient models to study tree-
crop interaction effects over a wide range of spacing. Special features of this model are as follows:
a. Spacing for trees is fixed on each spoke
b. Tree rows radiates towards outside from the hub
c. Even on a small area; growth of the trees can be assessed and compared between and among the
species over the wide range of spacing
d. It is the most effective and demonstrative block design to date to experiment on singular and multiple
species
e. Spacing to the nearest neighbour progressively varies
f. Data could be regenerated for regression modeling
g. Spacing x Spacing interaction could be studied
h. Shape of the area available for each species is constant but the size increases radially.
i. Areas having irregular shapes too can be utilized for carrying out experiments j.
j. Aesthetically the model is appealing
 Limitations:
a) Requires some degree of skills in laying out grounds
b) Little implication on slopes

Over View of AFS in Nepal and Similar Agro-eco Zoning in the World:

 The country can be divided into five physiographic zones based on altitude: Terai, Siwalik, Middle
Mountain, High Mountain and High Himal. Terai is a fl at and plain land inclining gently towards
south of Nepal with average elevation from 70 to 300 meters. On its north lies Siwalik, the elevation
between 300 m to 920 m. The Middle Mountains are located at an altitude between 200 m and 30001
m between the Terai and the High Mountains. The High Mountain and High Himal fall in the
northernmost part of the country on the border with China. The altitude in these regions is typically
more than 2300 m.
 Climatically, the country can be divided into three distinct seasons. Cold season from October to
February, Hot and dry season from March to mid-June and Rainy season from Mid-June to the end
of September. The average annual rainfall in Nepal is about 1,600 mm. The eastern region is wetter
than the western region due to early and higher rainfall. Eighty percent of precipitation comes in the
form of the summer monsoon rain prevailing in the country from June to September. Winter rains are
more common in the western hills. Temperature varies with topographic variations in the country. In
the Terai, winter temperature is between 22° -27° C while summer temperature exceeds 37°C. In the
mid-hills, temperature is between 12° – 16° C and in higher up occasionally it snows.
 Nepal has a population of 26.5 million with the population density of 180 people per square
kilometer. Approximately 70% of the people are forest dependent and 66% of the population live off
a combination of agriculture and forest products. The economic growth of the country in terms of
Gross Domestic Product (GDP) was 3.5 % in the year 2010/2011. Agriculture and Forestry are
estimated to contribute about 33% of the GDP followed by non-agriculture sector such as industry,
housing rent, and the real market (67%). The Human Development Index is 0.55According to the
new constitution of Nepal (2072), the country is divided into seven (7) Pradesh (provinces).

Table : Number of districts in each Pradesh (province) and forests area coverage.

Provi # Districts Name Total land Forest Forest Total %

nce # Districts area (ha) area (ha) area (%) forest
1 14 Taplejung, Panchthar, Illam, 25,90,500 11,34,250 43.78 17.3
Sakhuwa sabha, Tehrathum,
Dhankuta, Bhojpur, Khotang,
Solukhumbu, Okhaldhunga,
Udayapur, Jhapa, Morong and
Sunsari
2 8 Saptari, Siraha, Dhanusha, 9,66,100 2,63,630 27.29 4.4
Mahottari, Sarlahi, Rautahat, Bara
and Parsa
3 13 Dolakha, Ramechap, Sindhuli, 20,30,000 10,90,877 53.74 17.5
Kavrepalanchok, Sindhupalchok,
Rasuwa, Nuwakot, Dhadhing,
Chitawan, Makawanpur,
Bhaktapur, Lalitpur and
Kathmandu
4 11 Gorkha, Lamjung, Tanahun, 21,50,400 7,96,991 37.06 11.7
Kaski, Manag, Mustang, Parbat,
Syanja, Myagdi, Baglung and
Nawalparasi (Barda ghat East of
Susta)
5 12 Nawalparasi (Bardaghat West of 22,28,800 9,87,445 44.30 15.9
 Susta), Rupandehi, Kapilbastu,
Palpa, Arghakhanchi, Gulmi,
Rukum (East side), Rolpa,
Piyuthan, Dang, Banke and
Bardiya
6 10 Rukum (West side). Salyan, 27,98,400 11,90,631 42.55 16.1
Dolpa, Jumla, Mugu, Humla,
Kalikot, Jajarkot, Dailekh and
Surkhet.
7 9 Bajura, Bajhang, Doti, Acham, 19,53,900 11,46,106 58.66 16.9
Darchula, Baitadi, Dadeldhura,
Kanchanpur and Kailali.
Total 77 1,47,18,10 66,09,930 44.91 100
0
Source: Forest Research and Survey Department, 2016

MAJOR AGROFORESTRY SYSTEMS IN SOUTH ASIA

 The objectives of practicing agro forestry in all the countries of South Asia are the same i.e meeting
household fuel wood requirement, fodder for livestock, grazing, conserving soil and water utilizing
traditional agro forestry knowledge and technologies, learnt from their forefathers. However,
depending on the countries, some of the practices is very diverse and tends to be complex.
 Integration of crop production, grazing animals and forest areas into a mutually supportive system is
the main features of agro forestry being practiced in Bhutan. Ruminant (yaks and sheep) plays a
critical role by providing draught power, manure and livestock products for sale or home
consumption in this country.
 Planting trees on homestead and along the vicinity of farmland boundaries is common in
Bangladesh.
 Agro forestry in India is more developed in comparison to other South Asian countries. India has
already promulgated Agro forestry policy in the country. Both farm and forest-based Agro forestry
systems are being practiced but the intensity and use differs along with the argo-ecological zones of
the country. Silvo-pastoral practices are being practiced within village grazing grounds where
villagers have their tenure rights whereas this system in forests involve lopping trees and grazing
understory ground grasses.
 In Maldives, trees and shrubs species Griricidia (Gliricidia), Sesbania (Sesbania), Erythrina variegata
are being used in agro forestry practices as fodder for livestock and to serve as wind breaks.
Coconuts are extensively planted in and around homestead. Farmers are practicing trees as intercrops
in uniform grid pattern as it provides fl exibility in arranging the spacing between the trees and
individual farmer can remove them when they feel it necessary.
 In Sri-Lanka, agro forestry is one of the main sources of timber and food for the country. Two types
of home garden systems prevail in Sri-Lanka; traditional and modern. In the traditional system,
Jackfruit (Artocarpus integra) constitutes as an important component of most Sri-Lankan home
gardens for house hold consumption whereas modern home gardens look at more cash generation
through planting tree species that yield spices, beverages and sap. Sri-Lankan home gardens are
considered the most complex and diverse in the world.

The agro forestry systems commonly practiced in different regions of Nepal are as follows:
Terai
1. Home gardens
2. Planting trees among agricultural crops
3. Intercropping with horticultural crops
4. Taungya
5. Silvofisheary
6. Apisilvocultural system
 7. Silvopastoral system
8. Hortosilvopastoral system
Siwalik Hills:
1. Silvopastoral system
2. Taungya system
3. Silvofisheary
Middle Hills:
1. Alley cropping
2. Home garden
3. Hortosilvopastoral system
4. Contour hedge row system.
Higher Hills
1. Silvopastoral system
2. Contour hedgerow system

Agro forestry system and practices in Terai region are:

S.N Agro forestry systems Agro forestry practices

1 Agrisilviculture Camelia sinensis (Tea) under Albizia procera and Dalbergia sissoo,
Turmeric and ginger under Eucalyptus camaldulensis, Seasonal
agricultural crops under Tactona grandis Seasonal agricultural crops
along with mixed tree species
2 Hortisilviculture Banana along with Eucalyptus camaldulensis and Tectona grandis
Mango along with Eucalyptus camaldulensis and Tectona grandis
Avocado and pomegranate along with tree species Eucalyptus
camaldulensis and Mangifera indica along with asparagus,
citronella, palmarosa and mentha
3 Hortiagriculture Fruit trees along with seasonal agricultural crops
4 Agrisilvihorticulture Agricultural crops along with banana and tree species Fruit trees
and agricultural crops along with Tectona grandis, Shorea
borneensis and Dalbergia sissoo. Fruit trees, agricultural crops and
seasonal vegetables along with eucalyptus Mango and agriculture
crops along with Eucalyptus camaldulensis, Tectona grandis, Poplus
species, Melia azedarach
5 Agrosilvipastoral Agricultural crops along with Acacia catechu, Elaeocarpus ganitrusa
and pig farming. Agricultural crops, tree species along with grasses
and livestock
6 Silvofishery Fish farming in conjunction with Eucalyptus camaldulensis,
Tectona grandis , Mango and Dalbergia sissoo Fish farming along
Tectona grandis, Paulownia tomentosa, and Shorea borneensis
7 Agrosilvifishery Fish along with Eucalyptus camaldulensis, Tectona grandis and
seasonal crops.
8 Apiculuture Bee farming in conjunction with Tectona grandis and Paulownia
9 Agrohortosilvopastoral Agricultural crops and Areca catechu along with Tectona grandis,
Eucalyptus camaldulensis, Elaeocarpus sphaericus, Shorea
borneensis, Acacia catechu, and livestock

3. Agro forestry system and practices in Mid hill region are:

S.N Agro forestry systems Agro forestry practices

1 Agrisilviculture Tea under Alnus nepalensis Cardamom under Alnus nepalensis
Cardamom along with Thysanolaena maxima, Elaeocarpus ganitrus,
Alnus nepalensis, Schima wallichi and fodder tree species.
Cardamom and Coffee under Alnus nepalensis Coffee under
 multipurpose tree species Coffee, maize and seasonal vegetables
under Elaeocarpus ganitrus Cinnamomum tamala along with
agricultural crops Thysanolaena maxima along with Cinnamomum
tamala Kiwi, cardamom and Chiraito along with Taxus wallichiana,
Elaeocarpus sphaericus, Michlia champaca NTFPs along with
agricultural crops and tree species
2 Hortosilvipastoral Swertia chiraita, Zanthoxylum armatum along with fodder and fruit
trees Multipurpose trees, fodder trees, fruit trees, grasses along with
livestock
3 Hortiagriculture Mango and Banana along with Maize Pear along with maize and
seasonal vegetables Seasonal crops and vegetables under orange and
sweet orange Coffee under Orange, Banana, Walnut and Jackfruit
Zanthoxylum armatum along with orange and agriculture crops
4 Home garden Seasonal vegetables, fruit trees along with multipurpose trees
5 Silvopastoral Santalum album, Ziziphus budhensis, Schima wallichiana, Litsea
monopetala, Ficus semicordata, Toona ciliata and grasses along with
goat farming
6 Agrosilvihorticulture NTFPs along with fodder and fruit trees
7 Agrosilvipastoral Thysanolaena maxima along with fodder trees and livestocks
Cardamom and Cinamomun Tamala along with Elaeocarpus
ganitrus and Banana

Scenario of AFS in Similar other Agro-eco Zoning in the World:

Globally it has been acknowledged by FAO that about 30 to 33 % of the total geographical area must
be under good forest cover to maintain a harmony among the various components of nature.
Disastrous results of deforestation have already cast their shadows in many Asian countries. In
future, repercussions could be still more annihilating and horrible. Therefore, it would be quite
unwise to turn blind eyes to what had happened in Ethiopia. In many Asian countries, efforts are in
progress to rehabilitate and reclaim the degraded forests. Further, large scale plantation program
have been initiated under agro forestry and social forestry programs in areas outside the natural
forests. However, there have been little achievements in many underdeveloped and developing Asian
countries.

There has been substantial reduction in Asia‘s forest cover over the last thirty years. Although, about
30% of the land mass of tropical Asia and Pacific is forested, this varies widely by country from
almost 80% Papua New Guinea to only 2% in Pakistan. There have been several reasons for
deforestation resulting from a complex interaction of social, economic and edaphic factors. However,
economic and environmental repercussions of declining forest reserves are much more apparent.
Generally in Asia, experience has shown that negative economic effects become critical when forest
cover decreases below 0.2 ha/capita.
 Table 4: Forested land area and per capita forested area in selected tropical Asian countries
(1990)

Country % of total land area Per capita forest(ha/capita)

Pakistan 2.4 -
Bangladesh 5.9 -
India 17.4 0.1
Thailand 24.9 0.2
Vietnam 25.5 0.1
Philippines 26.3 0.1
Sri Lanka 27.0 0.1
Nepal 36.7 0.3
Myanmar 43.9 0.7
Malaysia 53.5 1.0
Indonesia 60.5 0.6
Cambodia 68.9 1.5
Papua New Guinea 79.5 9.0

Assignment:
1. What is Taungya system ? Give its advantages and disadvantages.
2. Differentiate between boundary planting and wind breaks in an agro forestry systems
3. Classify the Agro-forestry on the basis of arrangement of components.
4. Give an appropriate Agro-forestry system for Mid hills of Nepal Support your answers with diagram.
5. What is Neldes wheel model? Describe in brief.
6. Differentiate between
a) Contour hedgerow intercropping and alley cropping,
b) Iimproved fallow and bush fallow
c) Boundary planting and wind breaks
d) Riparian boundary and strip hedge row

Lect- 7 & 8

TREE CROP INTERACTIONS/INTERFACE

Introduction:
Tree-crop interactions Interaction is defined as the effect of one component of a system on the
performance of another component and/or the overall system (Nair, 1993). Regarding this, ICRAF
researchers have developed an equation for quantifying tree crop interaction (I), considering positive
effects of tree and crop yield through soil fertility enrichment (F) and negative effects through crop
competition (C) for growth resources between tree and crop I=F-C. If F> C, interaction is positive, if
F< C interaction is negative and if F=C interaction is neutral. Interaction occurs both above and
below ground and includes a complex set of interaction relating to radiation exchange, the water
balance, nutrient budget and cycling, shelter and other microclimatic modifications.
 There are a several complementary effects of tree crop interaction such as increased productivity,
improved soil fertility, efficient and balanced nutrient cycling, improved Soil conservation
management and improvement of Microclimate which are very important in the way of overall agro
forestry health and its

Interactions help to know

How the components of agro forestry utilize and share the resources of the environment, and
How the growth and development of any of the component will influence the others.

Nature of Interaction
1) Complementary:
In a system, if the tree and the crop component help each other, by creating favorable conditions for
their growth in such a way that the agro forestry system provides a greater yield than the yield of
their corresponding sole crops then it is called complementary interaction. It may be either spatial
or temporal.
2) Supplementary:
If two components interact in such a way that yield of one component exceeds yield corresponding to
its solo crop without affecting yield of the other component, the interaction is known to be
supplementary. For example, if the fodder yields from a tree is 20kg/tree and crop yield is 2 tones/ha
when grown separately but under agro forestry, the fodder (forage) yield from tree increased to 30
kg/tree without any reduction of crop yield, the interaction is supplementary in nature.
3) Competitive:
In this system, the tree and crop components interact in such a way that increase in the yield of one
component leads to decrease in the yield of other component due to competitive interaction. As in
the example of supplementary interaction, if the fodder yields of tree increases 30 kg/tree but crop
yield is reduced to 1.5 tones/ha or the crop yield increases to 2.5 tones/ha but forage decreases to 15
kg/tree. The interaction is competitive in nature.
 Factors affecting interaction:
1) Effect of species
The growth pattern varies from species to species and accordingly affects relationship with
associated components. Some crop may perform well in association with particular tree component,
whereas the yield of other crops may reduce with the same tree component, because different crops
interact differently with the same tree component.
2) Effect density
Canopy cover of trees intercepts light depending upon the density of trees and consequently affects
performance of underground crops. Generally, yield of underground crop decrease with increasing
density of trees. Trees also modify microclimate of crops grown below and improve physical
conditions and fertility of the soil.
3) Effect of age
The demand for various growth resources and therefore competition affected by the components
would be affected by age and growth of the components. Tree takes long time to attain full size and
stature, and thus no row space initially. Nevertheless, as the tree grows, their effect on crop growth
becomes apparent.
4) Effect of side factors
Climate, edaphic and physiographic features of an area affect plant growth, which varies in different
species and consequently interactive relationship of component species in an agro forestry system
also varies. For example, at one site highest mean forage yield was recorded in association with
Leucaenaleucocephala and at the other site, it was lowest in this combination. Variation in rainfall
also affects interactive relation of the components.
5) Effect of management
Various management practices may be adopted to favorably alter interactive relationship in agro
forestry situation. A tree species with all the desired characteristics is not available, tree crowns and
roots can be manipulated through management operations, mainly by pruning and thinning.

Different management options are as follows:

i. Microclimate amelioration
ii. Fertilization
iii. Application of mulch or manure
iv. Irrigation
v. Soil tillage
vi. Adapted species
vii. Supplemental feeding
These are for increasing growth whereas for decreasing growth are:-
i. Pruning
ii. Pollarding (cut off the top and branches of a tree to encourage new growth at the top.)
iii. Root pruning
iv. Trenching
v. Excess shading
vi. Herbicide application
vii. Grazing/browsing

Types of interaction

The major types of interaction between tree and crop components in an agro forestry system can be
classified as: 1) Positive (beneficial) & 2) Negative (harmful)
1) Positive interactions
a) Increased productivity b) Improved soil fertility c) Natural cycling
b) Soil conservation e) Water conservation f) Wood control
g) Microclimate improvement
2) Negative interactions
 a) Competition b) Allelopathy c) Pest and Disease

Methods for Quantifying Interactions

Tree crop interactions depend upon availability of growth resources, site conditions and moisture/
nutrient status of site. In mixed cropping system many indices such as aggressivity,competition
ratio, land equivalent ratio, relative crowding coefficient have been used to quantify interaction..

1) Land Equivalent ratio

LER =

LER = 1, no advantage
>1, beneficial
<1, more law is needed
LER is the ratio of the area under sole cropping to area under intercropping (X and Y are the
component crop)
2) Competition Indices
RCC =
RCC is the relative crowding coefficient, if this value exceed 1, species X is competitive than species
Y
3) Tree-Crop Interaction
To quantify effects of various factors in an agro forestry, a simple tree crop interaction (TCI)
equation has been developed by Anon. (1993).
I (Interaction) = F- C±M + P + L
Where, F = benefit of tree pruning
C = reduction in crop yield
M = consequences of above ground changes in temperature
P = consequences of change in soil properties
L = reduction of losses of nutrient or water

Advantages of tree/crop interface studies

1) Choice of Species
Especially, for screening alternative combinations of woody perennials and agricultural crops.

2) Design of Agro forestry Systems

The initial choice of whether a zonal or mixed cropping system is likely to be most productive
cannot satisfactorily made useless information about the ‗interface‘ is known. For example, if the
overall biological effect at the tree/crop interface is generally positive, then the amount of interface
can be maximized (=mixed cropping). If it is negative, it can be minimized (=some of the zonal
cropping or limited mixed cropping)

3) Management of Agro forestry System

Negative effects can be avoided through such practice as modifying the time of planting of the
agricultural crops, changing the ideotypes used, or by choosing cultivars with more appropriate
physiological responses or again by limiting the components by harvesting then at appropriate times
or b some form of pruning or training.
The amount of land needed for tree/crop interface studies is relatively little compared to that of
conventional field trials. Basically, all that is needed are a few trees and a small area of crop(s).
Tree/crop interface will result in and be a consequence of changes in environmental resource pools,
shelter effects etc

Environment and tree/crop interactions in agro forestry.

 Quantification of Agro forestry Products, Basal Cover, Canopy Cover , Spacing &Planting of
Agro forestry Species

Diameter and girth measurement

Diameter and girth measurement help to quantify the timber, firewood and other non-timber
products.
How to measure?
a) Diameter of logs are measured at thick and thin end or at the middle of the logs e.g.
diameter at thick end = dl
diameter at thin end = d2
diameter at mid end = dm

Some numerical
1. Calculate the volume of plant from the given width= 8 inch, thickness= 1 inch, length= 6 feet
Solution:
Volume = Thickness* Width* Length* π
V = (1/12)*(8/12)*6* π (1 feet = 12 inch)
= 0.316*π
= 0.9922ft3~ 1ft3
2. Calculate volume and total cost of the following logs at the saw-mill; if the sawing cost is Rs.
30/ft3 .
Log no Girth(inch) Length(ft) Volume(ft3)
1 51 13 ?
2 56 8 ?
3 37 4 ?
4 49 7 ?
5 59 8 ?

Solution,
By using Quarter Girth Formula,
Volume= (g/4)2 * L (g= girth in feet & L=Length in feet)
For Log no. 1
V = [(51/12)-4]2*13
= (51/12)*(51/12)*(l/4)*(l/4)
= 33813/2304 =14.67 ft3
Similarly, for Log no. 2
V=10.88 ft3
For log no. 3
V=2.37 ft3
For log no. 4
V= 7.29 ft3
For log no. 5
V= 12.08 ft3
So, Total volume = 47.29 ft3
1cft. = Rs.30
47.29c ft. = Rs. 1418.70
3. Calculate the volume of the log, when the length is 12 feet and girth is 48 inch. By using
Quarter Girth formula,
Volume= (g/4)2 * L
= [(48/12)- 4]2 * 12 = 12 ft3
4. Calculate the volume of a 10m long log and diameter was measured as 60 cm
Given,
Length of the log(L) = 10m
Diameter of the log(d) = 60cm
By using Huber‘s formula,
Volume= Lg(m2)
Where g= cross sectional area at the midpoint of the log
Then,
V=L*(πd2)/4
= 10*{3.14*(0.6)2}/4
= 10*0.283= 2.8 m3

5. Calculate the volume of a log whose length is 10 m and diameter measurement was as
follows:
d1=50cm, d2=45 cm, d3=40 cm
dmean=(0.5+0.45+0.40)/3
= 45 m
usingdmeanvalues,
g(m2) = (πd2mean)/4
= (3.14 * 0.452 )/4 = 0.1589 m2
Now,
Volume = Lg(m2)
= 10 * 0.1589
 = 1.589 ~1.6 m3
Also, According to Newton‘s Formula,
V=L * (gb + gm + gt )/3 (where b= base girth, m= mid girth & t=top girth)
= 1.6 m3
6. Calculate the diameter at the mid-section of a log from the following.
Volume=1.6m3, gb= 0.196m2, gt= 0.1256m2
According to the Newton‘s Formula,
V= L* (gb + gm + gt)/3
1.6 =10*(0.196+gm+0.1256)/3
(1.6*3)/10 = 0.196 + gm+ 0.1256
0.48= 0.321 +gm
gm= 0.48-0.321
(πd2)/4 = 0.159
d2= (0.159*4)/ TC
d2= 0.2025
d = 0.2025
d = 0.45 m = 45 cm
7. Calculate the volume of the log having following data
a. Girth(g)= 51 inch & Length(L)= 13 feet b. g= 56 inch & L= 8 feet
Quarter girth formula Quarter girth formula
2
V= (g/4) * L V= (g/4) 2 * L
= {(51/12) * (1/4)}2 *13 = {(56/12) * (1/4)}2 *8
3
= 14.67 ft =10.8 ft 3
8. Calculate the vertical projection of a tree which is leaned up to a distance of 5 m from the
base and the length of the tree along its stem was measured 20 m.

height of leaning or crooked tree (L) = (b2 +h2)

20 = (52 + h2)
400= 25 + h2
h2 = 400-25
h = 375 = 19.36 m

9. Calculate the third diameter of Meliaazadarach from the

10. given information;

dCom=78.26cm , d 1=45 cm , d2=40 cm , d3=??

We have,
dcom= (d2i + d22 + d23 )
now,
or, 78.26 = ( 452 + 402 + d23)
or, (78.26) 2= 2025 + 1600 + d23
or, 6124.6 = 2025 + 1600 +d23
or, d23 = 2499.6
or, d3 = 2499.6
= 49.99~ 50 cm
 10. Calculate the projection of ground occupied (mean basal cover/area by 100 Meliaazadarach
trees on an agro forestry plot whose mean circumference at the base was measured as 100 cm.
a) Proportion of ground occupied by 1 tree = (C2)/ (4π) (where C= Circumference)
= (100 x 100 )/(4*3.14)
= 10000/12.56
= 796.17 cm2
= 0.0796 m2
Hence, area occupied by 100 trees,
= 100* 0.0796 = 7.96 m2
~8m2
11. Estimate the diameter of Melia at a height of 10 m using the following information:
Total height of the tree = 20 m
Average taper = 1 cm/m height
Diameter at breast height (dbh) = 20cm
Difference between the height wherediameter is to be taken and the dbh = 10m - 1.3m= 8.7 m
[Note: dbh is taken at 1,3m at the standing tree]
Since, the average taper along the vertical projection of the tree is lcm/m height of the tree, the total
taper would be 8.7 cm
Hence, estimated diameter= 20cm-8.7cm
= 11.3cm= 11.3cm
12. If di, d2 , d3 measured as 15, 20 & 25 cm respectively, estimate dcom (combined diameter)
and interpret your results.
dcom= (d2, + d22 + d23 )
= (152 + 202 + 252)
= l250= 35.95 cm
13. Calculate the canopy height of the tree if the total height is 30m and clean bole is 5m.
Canopy height= Total tree ht. - clean bole
= 30-5=25 m
14. Calculate the spacing of plants, if there are 400 plants in a hectare of plantation raised on
square planting pattern.
No. of plants = (100* 100 )/ (square planting distance)
400 = 10000/ x (suppose)
X = 25 m
Spacing = (100 * 100)/ (No. of plants per ha)
= (100 * 100)/400 = 25mi.e 25*25 m2 Spacing

Planting of Agro forestry in different methods

1) Line Planting; no. of plants= (100*100)/(distance within rows * distance between rows)
2) Triangular Planting; no. of plants=(100*100*1.155)/(square of planting distance)
3) Quincunx planting; no. of plants=(l 00* 100*2)/( square of planting distance)
4) Rectangular Planting; no. of plants=(100*100)/(Row to row distance * Plant to plant distance)
5) Triangular; Spacing=( 100*100* 1.155)/(no. of plants per ha)
6) Quincunx; Spacing=( 100*100*2)/(no. of plants per ha)
7) Canopy extension (area)= (di*d2)/(47t) where di &d2 are diameter of canopy
8) Crown diameter N W

E S (ground cover)
Notable notes
a) Plant having < 10 cm diameter is not taken is not taken diameter at breast height
b) Diameter at breast height (dbh) should be taken at 1.37 m height (vertically) of the tree
c) Basal diameter is taken 30 cm above the ground
d) Bole height is the distance between ground level and crown point
Measurement of branch wood
Except thick branches most of the branches are converted into firewood with the increasing demand
for fuel wood, it is essential to access its volume. Billet is the stack of fuel wood that is laid in the
form of rectangular parallel epipeds. This cubical volume is taken as a fuel wood volume. If the stack
is on sloping ground, the length is measured horizontally and not along the slope. In stacked fire
wood, an allowance is often made by reducing the height of the stack on the basis of experience. The
loss of weight on driage is around 40-50 % for most of the species. This value varies with species;
e.gQuercusincana 20-30 % ,Rhododendron arborizum> 50 % , other Quercusspp 75 % etc.

Solid Volume of firewood

Stacked Volume is not the actual volume of fuels. This value of fuel is based on the solid content.
The solid volume of firewood depends upon the factors such as stacking, form of billets, length and
diameter of the billets. The solid volume can be assessed by any one of the following ways;
a) Xylometric metric method
Xylometric is a graduated vessel and volume of wood is calculated by the principle of water
displacement. The wood pieces are submerged in the water in the vessel. The volume increment in
the vessel gives the actual solid volume of wood. As the stack volume is huge, a sample portion is
utilized and results extrapolated (estimate on the basis of data available) for the whole log using the
formulae given;

V=(W*v)/w or W/w=V/v
Where, W= weight of the whole stack
w=weight of the submerged pieces
V=Volume of the whole stack
v=Volume of sample taken

b) Specific gravity method

This is the ratio of the density of a substance to that of water. Actually it is relative density (mass of
the unit volume of a substance i.e kg/cubic meter, gram/cubic centimeter or pound cubic foot) . The
fuel wood weight is calculated by using the relationship between the specific gravity and volume of
the wood.

Volume (V) = (Weight)/(Specific gravity) or SG=V/W

Assignment:
1. What is tree crop interaction ? Explain its nature and affecting factors for crop
2. Calculate volume and total cost of the following logs at the saw-mill; if the sawing cost is
Rs. 30/ft3

Log no Girth(inch) Length(ft) Volume(ft3) Cost Rs.

1 45 11 ? ?
2 66 7 ? ?
3 57 5 ? ?
4 69 8 ? ?
5 79 6 ? ?

3. Calculate the volume of a log whose length is 20 m and diameter measurement was d 1=50cm,
d2=45 cm, d3=40 cm

4. Calculate the diameter at the mid-section of a log from the following.

Volume=2.6m3, gb= 0.160m2, gt= 0.120m2
5. Calculate the third diameter of Meliaazadarach from the given information;
dCom=80.5cm , d 1=40 cm , d2=50 cm , d3=??

Lect-9 & 10

SOIL MANAGEMENT UNDER AGROFORESTRY SYSTEM (AFS)

Introduction
Degradation of natural resource viz soil, water, forest and climate is a major problems in modern
agriculture. Out of which the soil and water the degradation to cause thread under sustainability of
agriculture because decline productivity, profitability, imbalance in ecological system and
environmental security. All these problems can be addressing through Agro forestry, it is viable
option to maintain agriculture sustainability.
Proper land use planning is important for increasing agricultural production, environmental
conservation, and for the protection of biodiversity. The land use decisions and governmental efforts
for implementing land use are poor in Nepal. Although a land use policy was formulated in 2012 in
Nepal, the practical application of this policy is difficult because of its flexibility and many loopholes
within it.
The poor soil management practice in cultivated lands has led to a higher rate of soil erosion,
decreased crop production and productivity, and declined soil quality. It is estimated that 60% soils
of Nepal have low organic matter (OM), 23% have low phosphorus (P), 18% have low potassium
(K), and 67% of the soils are acidic. It has been estimated that 310 kg ha−1 of plant nutrient is lost
annually because of the cereal-based farming system, whereas only 67 kg ha−1 of fertilizer is added
to the soil through various fertilizer sources.
It is necessary to understand the efficiency of land use systems in terms of nutrient cycling and soil
conservation. Additionally, agricultural practices such as fertilization, tillage, irrigation, and crop
residue left on the field alter soil chemical properties and nutrient dynamics throughout the soil
profile. Changes in land use can also disrupt carbon and nitrogen dynamics and organic matter
content in soil.

SOIL DEGRADATION

Soil degradation is the decline in soil condition caused by its improper use or poor management,
usually for agricultural, industrial or urban purposes. It is a serious environmental problem. Soil
degradation results in a reduced productive potential and a diminished capacity of land to produce
benefits for humanity.

Major Causes of Soil Degradation

1. Physical Factors
There are several physical factors contributing to soil degradation distinguished by the manners in
which they change the natural composition and structure of the soil. Rainfall, surface runoff,
floods, wind erosion, tillage, and mass movements result in the loss of fertile top spoil thereby
declining soil quality.
All these physical factors produce different types of soil erosion (mainly water and wind erosion)
and soil detachment actions, In the long-term, the physical forces and weathering processes lead to
the decline in soil fertility and adverse changes in the soil‘s composition/structure.

2. Biological Factors
Biological factors refer to the human and plant activities that tend to reduce the quality of the soil.
Some bacteria and fungi overgrowth in an area can highly impact the microbial activity of the soil
through biochemical reactions, which reduces crop yield and the suitability of soil productivity
capacity.
Human activities such as poor farming practices may also deplete soil nutrients thus diminishing soil
fertility. The biological factors affect mainly lessens the microbial activity of the soil.
3. Chemical Factors
The reduction of soil nutrients because of alkalinity or acidity or water logging are all categorized
under the chemical components of soil degradation. In the broadest sense, it comprises alterations in
the soil‘s chemical property that determine nutrient availability.
It is mainly caused by salt buildup and leaching of nutrients which corrupt the quality of soil by
creating undesirable changes in the essential soil chemical ingredients. These chemical factors
normally bring forth the irreversible loss of soil nutrients and production capacities such as the
hardening of iron and aluminum-rich clay soils into hardpans.

4. Deforestation
Deforestation causes soil degradation on the account of exposing soil minerals by removing trees and
crop cover, which support the availability of humus and litter layers on the surface of the soil.
Vegetation cover primarily promotes the binding of the soil together and soil formation, hence when
it is removed it considerably affects the capabilities of the soil such as aeration, water holding
capacity, and biological activity.

5. Misuse or excess use of fertilizers

The excessive use and the misuse of pesticides and chemical fertilizers kill organisms that assist in
binding the soil together. Most agricultural practices involving the use of fertilizers and pesticides
often entail misuse or excessive application, thereby contributing to the killing of soil‘s beneficial
bacteria and other micro-organisms that help in soil formation.
The complex forms of the fertilizer‘s chemicals are also responsible for denaturing essential soil
minerals, giving rise to nutrient losses from the soil. Therefore, the misuse or excessive use of
fertilizers increases the rate of soil degradation by destroying the soil‘s biological activity and builds
up of toxicities through incorrect fertilizer use.

6. Industrial and Mining activities

Soil is chiefly polluted by industrial and mining activities. As an example, mining destroys crop
cover and releases a myriad of toxic chemicals such as mercury into the soil thereby poisoning it and
rendering it unproductive for any other purpose.
Industrial activities, on the other hand, release toxic effluents and material wastes into the
atmosphere, land, rivers, and groundwater that eventually pollute the soil and as such, it impacts on
soil quality. Altogether, industrial and mining activities degrade the soil‘s physical, chemical, and
biological properties.

7. Improper cultivation practices

There are certain agricultural practices that are environmentally unsustainable and at the same time,
they are the single biggest contributor to the worldwide increase in soil quality decline. The tillage
on agricultural lands is one of the main factors since it breaks up the soil into finer particles, which
increase erosion rates.
The soil quality decline is exuberated more and more as a result of the mechanization of agriculture
that gives room for deep plowing, reduction of plant cover, and the formation of the hardpan.
Other improper cultivation activities such as farming on steep slope and mono-cropping, row-
cropping, and surface irrigation wear away the natural composition of the soil and its fertility and
prevent soil from regenerating.

8. Urbanization
Urbanization has major implications on the soil degradation process. Foremost of all, it denudates the
soil‘s vegetation cover, compacts soil during construction, and alters the drainage pattern.
Secondly, it covers the soil in an impermeable layer of concrete that amplifies the amount of surface
runoff which results in more erosion of the topsoil. Again, most of the runoff and sediments from
urban areas are extremely polluted with oil, fuel, and other chemicals.
Increased runoff from urban areas also causes a huge disturbance to adjacent watersheds by changing
the rate and volume of water that flows through them and impoverishing them with chemically
polluted sediment deposits.

9. Overgrazing
The rates of soil erosion and the loss of soil nutrients, as well as the topsoil, are highly contributed by
overgrazing. Overgrazing destroys surface crop cover and breaks down soil particles, increasing the
rates of soil erosion. As a result, soil quality and agricultural productivity are greatly affected.

Fatal Effects of Soil Degradation

1. Land degradation
Soil quality decline is one of the main causes of land degradation and is considered to be responsible
for 84% of the ever-diminishing acreage. Year after year, huge acres of land lost due to soil erosion,
contamination, and pollution.
About 40% of the world‘s agricultural land is severely diminished in quality because of erosion and
the use of chemical fertilizers, which prevent the land from regenerating. The decline in soil quality
as a result of agricultural chemical fertilizers also further leads to water and land pollution thereby
lowering the land‘s worth on earth.

2. Drought and aridity

Drought and aridity are problems highly influenced and amplified by soil degradation. As much as
it‘s a concern associated with natural environments in arid and semi-arid areas, the UN recognizes
the fact that drought and aridity are anthropogenic induced factors especially as an outcome of soil
degradation.
Hence, the contributing factors to soil quality decline such as overgrazing, poor tillage methods,
and deforestation are also the leading causes of desertification characterized by droughts and arid
conditions. In the same context, soil degradation may also bring about loss of biodiversity.

3. Loss of arable land

Because soil degradation contributes to land degradation, it also means that it creates a significant
loss of arable land. As stated earlier, about 40% of the world‘s agricultural land is lost on the account
of soil quality depreciation caused by agrochemicals and soil erosion.
Most of the crop production practices result in the topsoil loss and the damage of soil‘s natural
composition that makes agriculture possible.

4. Increased flooding
The land is commonly altered from its natural landscape when it rids its physical composition from
soil degradation. For this reason, the transformed land is unable to soak up water, making flooding
more frequent.
In other words, soil degradation takes away the soil‘s natural capability of holding water thus
contributing to more and more cases of flooding.

5. Pollution and clogging of waterways

Most of the soil eroded from the land together with the chemical fertilizers and pesticides utilized in
agricultural fields are discharged into waterways and streams. With time, the sedimentation process
can clog waterways, resulting in water scarcity.
The agricultural fertilizers and pesticides also damage marine and freshwater ecosystems and limit
the domestic uses of the water for the populations that depend on them for survival.
Solutions of Soil Degradation

1. Reducing deforestation
Avoiding deforestation completely is an uphill task. However, deforestation can be cut down and this
can create an impressive way of reshaping and restoring forests and vegetation cover.
As populations grow, individuals can be sensitized and educated regarding sustainable forest
management and reforestation efforts. Also, preserving the integrity of guarded areas can
significantly reduce demonstration.
Hence, there is a necessity for individuals all over the world to respect forest cover and reduce some
of the human-driven actions that encourage logging. With the reduction of deforestation, soil‘s
ability to naturally regenerate can be restored.
Governments, international organizations, and other environmental stakeholders need to ensure there
are appropriate measures for making zero net deforestation a reality so as to inhibit soil degradation.

2. Land reclamation
Land reclamation encompasses activities centered towards restoring the previous organic matter and
soil‘s vital minerals. This may include activities such as the addition of plant residues to
degraded soils and improving range management.
Salinized soils can be restored by salt level correction reclamation projects and salinity control. One
of the simplest but most forgotten methods of land reclamation is the planting of vegetation such as
trees, crops, and flowers over the affected soils. Plants act as protective covers as they are helpful at
making the soil stronger by stabilizing the land surface.

3. Preventing salinization
Just like the old adage states that ―prevention is better than cure,‖ so does the same concept apply in
solving the worldwide problem of soil degradation through salinization. The costs of preventing
salinization are incredibly cheaper than the reclamation projects in salinized areas.
Consequently, actions such as reducing irrigation, planting salt-tolerant crops, and improving
irrigation efficiency will have high payoffs because the inputs and the labor-demanding aspects
associated with reclamation projects are zero. Preventing salinization in the first place is thus
an environmentally friendly means of offering a solution to soil degradation.

4. Conservation tillage
Proper tillage mechanisms hold as one of the most sustainable ways of avoiding soil quality decline.
This is otherwise known as conservation tillage, which means tillage mechanisms targeted at making
very minimal changes to the soil‘s natural condition and at the same time improving the soil‘s
productivity.
Examples include leaving the previous year‘s crop residue on the surface to shield the soil from
erosion and avoiding poor tillage methods such as deep plowing.

Soil Erosion
Soil erosion is the displacement of the upper layer of soil; it is a form of soil degradation. This
natural process is caused by the dynamic activity of erosive agents, that is, water, ice, snow, air,
plants, animals, and humans.
Erosion, whether it is by water, wind or tillage, involves three distinct actions – soil detachment,
movement and deposition. Topsoil, which is high in organic matter, fertility and soil life, is relocated
elsewhere "on-site" where it builds up over time or is carried "off-site" where it fills in drainage
channels. Soil erosion reduces cropland productivity and contributes to the pollution of adjacent
watercourses, wetlands and lakes.
Soil erosion can be a slow process that continues relatively unnoticed or can occur at an alarming
rate, causing serious loss of topsoil. Soil compaction, low organic matter, loss of soil structure, poor
internal drainage, salinisation and soil acidity problems are other serious soil degradation conditions
that can accelerate the soil erosion process.
 At normal geological pace, nature requires 1000 years to build up 2.5 cm of top soil, but wrong
farming method may take only a few years to erode it from the land of average slope.

Types of Soil Erosion

One of the most important things that we can do to ensure the health of our crops and nearby
ecosystems is to reduce soil erosion. The different soil erosion types are explained below.

A. Geological Erosion:
Erosion is the geological process in which earthen materials are worn away and transported by
natural forces such as wind or water. A similar process, weathering, breaks down or dissolves rock,
but does not involve movement. ... Most erosion is performed by liquid water, wind, or ice (usually
in the form of a glacier).

B. Accelerated Erosion:
Accelerated soil erosion occurs when anthropogenic processes modify soil, vegetation, or climatic
conditions causing erosion rates at a location to exceed their natural variability. ... Land use impacts
that are constrained within the range of natural variability should not result in accelerated soil
erosion.
1. Rain Drop or Splash Erosion
The erosion due to the impact of falling raindrops on soil surface leading to the destruction of the
crumb structure is known as the raindrop or splash erosion.
2. Sheet Erosion
It is the uniform removal of soil in thin layers from the land surface caused by the wind. Land areas
with loose, shallow topsoil overlie compact soil are most prone to sheet erosion
3. Rill Erosion
Rill erosion is a form of water erosion in which the erosion takes places through numerous narrow
and more or not so straight channels called streamlets, or head cuts. Rill is the most common form of
erosion, which you can also observe during heavy rain.
4. Gully Erosion
Gully erosion occurs due to the runoff of surface water causing the removal of soil with drainage
lines. Gullies when started once, will move by headword erosion or even by slumping of side walls
unless and un-till proper steps will be taken in order to stabilize the disturbance.
5. Stream Bank Erosion
Bank erosion is nothing but washing up away from banks of a stream or a river. It is different from
the erosion of the bed of a watercourse, which is referred to as scouring. This type of erosion is also
termed as Stream Bank Erosion.

Causes of Soil Erosion

Running water is one of the main cause of soil erosion. Some soil erosion causes are mentioned
below.
1. Due to Soil Texture
If the texture is loose that is the soil contains more of small grains and of open structure erodes
faster.
2. Slope
Soil present in a steeper slope more than the soil present at a plane level of the ground.
3. Intensity or Amount of Rainfall
More intense rain, more erosion. This can be a bit slow if there are more trees present in the land as
the roots of the plants hold soil in a firm manner.
4. Human Activities
Agricultural practices, deforestation, roads and urbanization and global warming are a few major
causes of soil erosion.
5. Deforestation
 Mismanaged utilization of soil resources like the removal of forest cover causes soil erosion heavily.
Due to increasing land demand, the human is more into deforesting lands. Tree roots act as a binder
of the top layer of the soil.

The consequences (Effect) of soil erosion are as follows:

1) Land degradation: which is caused by water and wind erosion, shifting cultivation, degraded
forest, landslide's etc. (about 30%)
2) Siltation in the multipurpose reservoir and production yield.
3) Floods and flood plains: productive agricultural land might go out of cultivation in flood plains
due to silt deposition.
4) Productivity of agricultural lands: the effect of land degradation on productivity revealed that
highly or moderately degraded land yielded 10% less than non-degraded contour parts. In strongly
degraded lands, the production loss rises to 18%. In extreme cases production will be zero.
5) Environmental pollution: sediments is one of the major pollutants which we cannot reclaim the
soil.
6) Changing forest cover: Nepal has 39.6 % (forest + shrub) i.e. 29% forest and 10.6 % shrubs and
12% pasture lands. The forest cover is declining due to the degradation of permanent pastures and
human encouragement due to open forest.
7) Loss of Biodiversity: It is one of the major global concerns today. Nepal has 118 ecosystems, 35
kinds of forest and 19000 community forests.

Water Erosion
Soil erosion occurs through a 3-stage process, namely,
• Detachment
• Transportation
• Deposition

Factors influencing soil erosion by water

The following are the factors which influence soil erosion by water
• Climate; rainfall
• Soil: its characteristics
• Topography: slope length, slope steepness and slope shape
• Vegetation: presence of crop, forest, and vegetation management
• Human behavior; land exploitation and management

Wind erosion
Wind erosion is a significant problem in the arid grazing lands. It is most likely to occur when strong
winds blow over light-textured soils that have been heavily grazed during drought periods. It
contributes to scalding, a process that forms smooth, bare areas on impermeable subsoils.
These areas, which vary from a few square meters to hundreds of hectares, are difficult to revegetate
due to:
 lack of topsoil
 low permeability
 their often saline surface.
Generally, sandy soils are vulnerable to wind erosion because they cannot store very much moisture
and have low fertility.

SOIL AND WATE CONSERVATION APPROACHES

Introduction
In recent years, a new approach to soil and water conservation has been emerging, based on
experience gained through farming systems research. This approach, sometimes called land
husbandry, shifts the emphasis from looking only at what is happening to the soil (e.g., symptoms of
erosion) to examining why erosion is taking place (e.g., the underlying causes of erosion).
Examining the why component involves understanding the biophysical and socioeconomic factors
that contribute to land degradation.
Due to the biophysical characteristics, the loss of soil and water resources remains a critical problem.

Soil Conservation Approaches

The top soil layer contains mostly organic matter and nutrients which are very useful for plant
growth. In order to get better plant growth, the top soil layer must be protected from wind and water
erosion. Measures taken for protecting the top soil layer are called soil conservation measures. These
measures protect top soil either through reducing the impact of erosive agents (water and wind) or by
improving the soil aggregate stability or surface roughness. The soil conservation measures can be
broadly grouped into three categories namely, biological, mechanical, bio-engineering etc.

Soil and Water Conservation and Soil Fertility Management General Practices
1. Bench Terraces:
Bench terraces are a soil and water conservation measure used on sloping land with relatively deep
soils to retain water and control erosion. They are normally constructed by cutting and filling to
produce a series of level steps or benches. This allows water to infiltrate slowly into the soil. Bench
terraces are reinforced by retaining banks of soil or stone on the forward edges. This practice is
typical for rice-based cropping systems.
3. Contour tillage/planting
Contour tillage or planting is practiced on sloping lands to reduce soil erosion and surface runoff. A
contour is an imaginary line connecting points of equal elevation on the ground surface,
perpendicular to the direction of slope. Structures and plants are established along the contour lines
following the configuration of the ground.
4. Cover crops
Cover crops are grown to protect the soil from erosion and to improve it through green manuring (the
plowing-under of a green crop or other fresh organic materials). These are usually short-term crops
(less than two years), planted in fields or under trees during fallow periods. Cover crops are also
inter-planted or relay-planted with grain crops such as maize, or planted once in a cropping cycle.
Cover cropping is practiced in the Philippines and other Asian countries to suppress weeds under
rubber and coconut plantations and to provide forage for animals. Cover crops can also be used in
fallow systems to improve soil fertility quickly and shorten the fallow period.
5. Crop rotation
Various crop species are grown in sequence, one after another, in the same part of the farm or field.
These cropping patterns can vary from year to year; but they are designed to achieve a common
result: better soil physical and nutrient composition.
In agro forestry systems, the perennial crop component can be changed after a number of years. This
would be considered one rotation. The agricultural crop component can follow a shorter rotation
period, usually less than one year. Agro forestry requires a longer-term approach to rotations,
involving a wider variety of crops, each with a unique production cycle.
A typical crop rotation is rice-mungbean-corn-cowpea. Since legume crops increase soil nitrogen,
mungbean (Vigna sinensis) is planted after rice (Oryza sativa), to replenish some of the nitrogen and
other nutrients taken by the rice. Likewise, cowpea (Vigna radiata), with its nitrogen-fixing ability
and positive effects on soil, can be grown after corn (Zea mays), which places relatively high
demands on the soil.
6. Diversion ditches
Diversion ditches are constructed along the contour lines and across slopes for the purpose to
intercept surface runoff and divert it to suitable outlets. These ditches are the main soil conservation
structures to manage runoff in upland areas. Diversion ditches are dug at varying intervals,
depending on the steepness of the slope; the steeper the slope, the closer the interval. Ditches follow
the contour, they are 1 meter wide at the top, 0.5 meter wide at the bottom and 0.5 deep.
Waterways dispose of the excess flow in diversion drains and surface runoff and channel it to the
natural drainage channels.
7. Drop structures
Drop structures are constructed to slow the flow of water in channels. In a steeply sloping channel,
erosion can be controlled by allowing the water to flow over a series of steps, or drop structures.
Though effective, these structures are quite expensive for ordinary farmers to construct. Drop
structures are more effective when combined with check dams. They can also be reinforced by
vegetative means, such as planting trees or shrubs.
8. Grass strips
Planting grasses along contour lines creates barriers to minimize soil erosion and runoff. It induces a
process of natural terracing on slopes as soil collects behind the grass barrier, even in the first year.
Grass can be planted along the bottom-and sides of ditches to stabilize them and to prevent erosion
of the upper slope. Grasses can also be planted on the risers of bench terraces to prevent erosion and
maintain the stability of the benches.
Grasses are trimmed regularly (every 2-4 months) to prevent them from flowering, shading and
spreading to the cropped area between the strips. Thus, grass strips can be very appropriate for
farmers who cut and carry fodder for their animals. Grasses can also be used as mulch for crops.
On hillsides, grass seeds or tillers are planted in double rows (50 cm apart) along the contour with
varying distances between the double rows. In ditches, tillers are planted close together in rows. On
the risers of bench terraces, they are planted in a triangular pattern at a spacing of 30 cm x 20 cm.
Examples of grass species commonly used are: setaria (Sitaria anceps), ruzi grass (Brachiaria
ruziiensis), napier or elephant grass (Pennisetum purpureum), guinea grass (Panicum maximum),
NB21 (Napier crossed with pearl millet), lemon grass (Cymbopogon citratus) and vetiver (Vetiveria
zizanoides).
9. Minimum tilIage/zero tillage
In this system, simple farm implements such as hoes and digging sticks are used to prepare land and
plant food crops. Minimum tillage is common and effective in controlling soil erosion, particularly
on highly erodible and sandy soils. Examples of minimum tillage operation are rice-cropping
systems in Vietnam and Thailand and taro cultivation in the Papua New Guinea lowlands.
10. Mulching
Mulching is a soil and water conservation practice in which a covering of cut grass, crop residues or
other organic materials is spread over the ground, between rows of crops or around the trunks of
trees. This practice helps to retain soil moisture, prevents weed growth and enhances soil structure. It
is commonly used in areas subject to drought and weed infestation. The choice of the mulch depends
on locally available materials. The optimal density of soil cover ranges between 30% and 70%.
In alley-cropping systems, hedgerow biomass is often used as mulch. In orchards, cover crops may
also be used as live mulches, especially around young trees that are well-established. Another
strategy is to leave crop residues on the ground after harvesting (e.g., pineapple tops, corn stover,
rice straw, etc.). This ensures that some nutrients are taken up by the plant and returned to the soil.

11. Ridge terraces

A ridge terrace consists of a furrow and ridge, constructed along the contour on sloping land (usually
less than 15%). Its purpose is to control soil loss and trap water. Grasses and legume trees are usually
used to stabilize the ridge, but fruit trees, banana and cassava are also commonly used. During the
wet season, the furrow fills with sediment and farmers put this back on to their land. Variations on
ridge terraces include alley cropping, contour tillage and sloping agricultural land technology
(SALT)
12. Shifting cultivation
This form of low-input agriculture and fallow management is common in Southeast Asia,
particularly in rice, taro and cassava-based systems. It is also commonly referred to as swidden
cultivation. If managed properly, it can be considered a sustainable practice, particularly in sparsely
populated areas. In this system, the underbrush is cut, then most of the trees are felled. Certain tree
species are left to stand and branches are pruned. In most places, underbrush is burned; but in parts
of Papua New Guinea, no-burn practices are used. The branches and leaves are slashed and may be
laid along the contour. Food crops are then planted using minimum tillage practices, such as dibble
or digging sticks.
13. Soil barriers
Soil barriers slow down runoff and retain the soil lost by sheet erosion. They may be made of wood
or rocks; over time, they may develop into live fences of trees and shrubs. In Papua New Guinea and
the Philippines, barriers are constructed with logs and branches across the slope. These are placed
against wooden stakes driven into the ground. The upper side of the barrier is filled with grass and
other materials to act as a sediment trap. The width of the cropland between barriers depends on the
slope gradient, but is usually 4 m to 8 m. Crops such as maize, sweet potato and tobacco are planted
in the alley.

14. Soil traps

Soil traps are structures constructed to harvest soil eroded from the upper slopes of the catchment.
The most common types of soil traps are check dams and trenches, built in diversion ditches or
waterways.
A check dam slows down the water flow and allows heavier soil particles to settle. The size of the
check dam depends on the size of the drainage or gully to be protected. Check dams can be built of
Gliricidia stakes, bamboo, loose rocks, logs or other locally available materials.
15. Water harvesting
Water availability for upland agriculture can be improved by smallscale impoundments to capture
and store rainwater for irrigation.
Small-scale water harvesting is most successful when operated as a system with three components:
the watershed or catchment area that generates the runoff; the reservoir which holds or collects the
runoff; and the service area where the harvested water is used for production.
A catchment area of sufficient size is needed to drain water into the reservoir. The amount of runoff
generated depends on the catchment characteristics and rainfall pattern (amount, duration and
intensity); hence, the variability of catchment sizes
15. Increase Organic Matter Inputs
To maintain or increase soil organic matter levels, inputs of organic matter must meet or
exceed the losses of organic matter due to decomposition. Healthy crops can be a valuable
source of organic matter, and crop residues should be returned to the soil to the extent possible.
Incorporation of cover crops or perennial crops and judicious additions of animal and green
manure and compost can also be used to increase or maintain soil organic matter.
Carefully planning the timing, application method, and quantity of manure, compost, and other
fertilizers will allow you to meet crop nutrient demands and minimize nutrient excesses.
Healthy, vigorous plants that grow quickly are better able to withstand pest damage. However,
overfertilizing crops can increase pest problems. Increasing soluble nitrogen levels in plants
can decrease their resistance to pests, resulting in higher pest density and crop damage.
Maintaining a soil pH appropriate for the crop to be grown will improve nutrient availability
and reduce toxicity. Maintaining adequate calcium levels will help earthworms thrive and
improve soil aggregation.
16. Reduce Pesticide Use and Provide Habitat for Beneficial Organisms
Beneficial insects that contribute to biological control or pest organisms can be harmed by the
application of broad-spectrum insecticides. Farmscaping is a whole-farm, ecological approach
to increase and manage biodiversity with the goal of increasing the presence of beneficial
organisms. Farmscaping methods include the use of insectary plants, hedgerows, cover crops,
and water reservoirs to attract and support populations of beneficial organisms such as insects,
spiders, amphibians, reptiles, bats, and birds that parasitize or prey on insect pests.
17. Windbreaks
As the name suggests, this soil conservation practice is used to reduce the power of winds and its
disruptive effect on soil. These are trees or bushes to shelter crops from snow and winds planted in
several rows. Depending on the number of rows, we can distinguish windbreaks properly (up to five
rows) and shelterbelts (six and more).

Role of agroforestry in soil quality/heath

Compared to natural, a managed agricultural ecosystem has greater amounts of nutrient flowing in
and out, less capacity for nutrient storage, and less nutrient recycling. The capacity of trees to
maintain or improve soils is shown by the high fertility status and closed nutrient cycling under
natural forest, the restoration of fertility under forest fallow in shifting cultivation, and the experience
of reclamation forestry and agroforestry (Young, 2003). The processes by which trees maintain or
improve soil fertility are given below:

1. Photosynthetic fixation of carbon and its transfer to the soil via litter and root decay,
2. Nitrogen fixation by all leguminous trees and in few non-leguminous species (e.g., Alder and
Casuarinas),
3. Improved nutrient retrieval by tree roots, including through mycorrhiza and from lower horizon,
4. Providing favorable conditions for the input of nutrients from rainfall and dust
5. Control of erosion by combination of cover and barrier effect, especially the former,
6. Root uptake of nutrients that would otherwise have been lost by leaching,
7. Soils under trees have favorable structure and water holding capacity, through organic matter
maintenance and root action,
8. Provision of a range of qualities of plant litter, woody, and herbaceous,
9. Growth promoting substances,
10. The potential through management of pruning and relative synchronizations of timing of release
to nutrients from litter with demand for their uptake by crops, and
11. Effects of tree shading on microclimate.

SOIL FERTILITY MANAGEMENT

Soil Fertility
“Soil fertility refers to the ability of the soil to sustain plant growth.”
Fertile soil results in high yield and better quality of plants. Fertile soil is rich in fundamental
elements and minerals, has good aeration, water holding capacity, and good texture.

Factors Affecting Soil Fertility

The following factors affect the soil fertility:

1. Mineral Composition
The mineral composition of the soil helps to predict the ability of the soil to retain plant nutrients.
Application of proper fertilizers and manures helps in enhancing the quality of the soil.

2. Soil pH
Soil pH helps in maintaining the nutrient availability of the soil. A pH range between 5.5-7 is
optimum for soil fertility.

3. Soil Texture
The minerals of different sizes are responsible for maintaining the structure of the soil. Clayey soil
can retain more nutrients and hence acts as a nutrient reservoir.

4. Organic Matter
Organic matter is a source of nitrogen and phosphorus. These can be mineralized and made available
to the plants.

Soil fertility Problems in Nepal

The population growth in Nepal is at faster pace and because of rapid urbanization
of cultivated area; the food produced within the country not enough. One of the factors for
increasing production of crops is nutrient- its availability and uses. The hills and mountains of
Nepal, farmers generally use farm yard manure or other organic sources of nutrients. The main
source of nutrients in hills and mountain of Nepal is organic based. The total fertilizer imported in
the country only 3% is distributed in the mountain area, 30% in mid hills while the rest 67% is
distributed and used in the terai region.

Two principal practices for maintaining soil fertility in the mid hills of Nepal are application of
FYM and/or application of chemical fertilizers. FYM and compost are the main sources of
plant nutrients and organic matter to the soil in the subsistence upland farming system of mid hills.
Soil erosion, poor organic recycling and unbalanced fertilization are the main reasons for soil
fertility decline in mid -hills of Nepal. It is estimated that erosion and run off of 1-rnm topsoil
remove 10 kg of nitrogen, 7 kg P and 15 kg of potassium from one hectare of land.
Soil Fertility Status

Soil Fertility Status of Nepal

The soils of Nepal are mostly acidic. According to the data of 2015, 53% of the soils of Nepal is
acidic,
33.51% is neutral and only 13.49% of the total soil is alkaline. Most of the soils of Nepal has low
organic matter content. About 45% of the soil has low organic matter content, 41% has medium and
the rest 14% has high organic matter content in the soil of Nepal. Similarly, 56% of the soil has low
total N content, 30% has medium and remaining 14% has high total N content. Phosphorus
availability depends on soil pH and the available phosphorus content in Nepalese soil is in
decreasing trend. About 42% of the soil has low, 27% of the soil has medium and the rest 30% has
high available phosphorus content. The soil of Nepal primarily had high potassium content but now
the situation is changing. About 50% of the soil has low potassium content, 26% has medium and
rest 24% has high potassium content in the soil. In a nutshell, it can be said that the nutrient
status of soil is depleting with time and replenishment of the soil nutrient is a must for sustained
crop production.
Soil Fertility Management in Terai
Soil Fertiility Management in Terai
Since intensive cultivation persist in Terai with improved varieties of major cereal crops, the
nutrient
management is critical. There is practice of high fertilizer use compared to other ecological belts.
The trend of soil fertility management has also been changing. Earlier, farmers use to till the land
with mould board plough and hence every farmer has oxen for ploughing. Now the situation has
changed. Due to mechanization in agriculture, heavy machineries are used for ploughing the field
and have contributed to the shortage of organic manure in Terai. Farmers have now stopped keeping
oxen that were once the source of organic manure, few farmers' rear milching cattle but the cattle
dung are used as fuel for cooking. This also has aggravated the decline in organic matter content
in the terai and the same situation prevails in hills and mountains.

Majority of the farmers in terai are used chemical fertilizers to replenish soil nutrients and for crop
production. FYM or compost is used as supplementary in terai. Due to higher intensive cropping, the
practice of green manuring is not much common. However, integration of legumes in the cropping
system is a common practice. Biofertilizers are rarely used during the productions of legumes and
other crops as well.

Rice based cropping system is mostly dominant in terai. Therefore, the demand for nutrients is
higher in
terai region. To fulfill the N demand, azolla application was once popular but this practice
also has been decreasing. Biogas slurry are mainly used for vegetables. Farm yard manure,
compost, vermicompost, crop residue incorporation, etc. are mostly prevalent but they are not
sufficient enough to meet the demand of the crop. Hence, mineral fertilizers are mostly used to meet
the crops‗ nutrient requirements.
Soil Fertility Management in Hills and Mountains

Soil Fertiility Management in Hills and Mountain

Hill farming is compost based and most of the farmers use organic manure as a major source
of
nutrients. Since little amount of the chemical fertilizer is supplied to the hills and mountains of
Nepal, mineral fertilizer is used as supplements for plant nutrients. Farmers that adopt organic
farming use cattle urine, biogas slurry and other organic sources like ash, forest soil, crop residue,
etc. for replenishing soil nutrients. In recent years, vermicomposting and biochar have gained
popularity in some areas. Legumes specially, beans are one of the major crops and due to this the
fertility of the soil is maintained to some extent. Most of the temperate fruits are not fertilized well.
The indigenous soil nutrients play key role in supplying nutrients to most of the crops. The crops
grown are less nutrient requiring and the yield of the crops over years do not fluctuate much.
Therefore, still some of the soils in hills and mountains are all organic by default.
Soil Fertility Management through organic inputs

Assignment
1. What are the factors of soil degradation? What are practices for soil fertility managements in
Nepal?
2. What are the impacts of soil erosion? What are the future strategies for controlling erosion?

Lect-11 & 12

DESIGNING AGROFORESTRY SYSTEMS

Introduction:
Agroforestry systems include both traditional and modem land-use systems where trees are managed
together with crops and/or animal production systems in agricultural settings. When designed and
implemented correctly, agroforestry combines the best practices of tree growing and agricultural
systems resulting in more sustainable use of land. The potential of agroforestry to contribute to
sustainable development has been recognized in international policy. Yet agroforestry continues to
face challenges such as unfavorable policy incentives, inadequate knowledge dissemination, legal
constraints and poor coordination among the multiple sectors to which it contributes

Conceptual Frame Work for Designing AFS:

Agroforestry D & D is a family of procedures for the diagnosis of land management problems and
potentials and the design of agroforestry solutions. The ICRAF has developed an approach to assist
agroforestry researchers and development fieldworkers to plan and implement effective research and
development projects.

Criteria of a good Agroforestry design:-

There is no substitute for good design. A good agroforestry design should fulfill the following
criteria:

A. Productivity:
There are many different ways to improve productivity with agroforestry: increased output of tree
products, improved yields of associated crops, reduction of cropping system inputs, increased labour
efficiency, diversification of production, satisfaction of basic needs, and other measures of economic
efficiency or achievement of biological potential.

B. Sustainability:
By seeking improvements in the sustainability of production systems, agroforestry can achieve its
conservation goals while appealing directly to the motivations of low income farmers, who may not
always be interested in conservation for its own sake.

C. Adaptability:
No matter how technically elegant or environmentally sound an agroforestry design may be, nothing
practical is achieved unless it is adapted by its intended users. This means that the technology has to
fit the social as well as the environmental characteristics of the land use system for which it is
designed.

Factors Affecting AFS Designing:

1. Climatic factors:
More than any other factor, climatic factors affect significantly the agriculture and Agroforestry
practices in any region.
 Rainfall, solar radiation, temperature, and humidity are important factors that directly affect
the crops planted in the Agroforestry systems.
 Rainfall also affect the rates of soil erosion, sediment yields and surface runoff.
The appropriate Agroforestry system may be the one which counterbalances the negative impacts of
these factors.
2. Biophysical factor:
 Site factory such as soli characteristics, slopes and terrain as well as plant communities play
an important roles in the development of Agroforestry practices.
 It is generally assumed that tropical soils are much older and infertile than temperate soils.
 Much of the fertility of the tropical soils aretiep up with biomass or the organic matter of
green plants.
 In slash-and-burn agriculture, removal of the plant biomass also decreases the fertility levels
of the soil.
 The increased soil erosion rate due the removal of the ground cover leads to faster
degradation of upland soils.
3. Socioeconomic factor:
 Most of the farmers in the upland hills and mountain are resource poor farmers and occupy
 the lowest economic strata of society.
 The farming is basically subsistence type. Food insecurity becomes a matter of great concern
for most of these fanners. Besides, they need some cash to buy essential goods from the
markets.
 Therefore, the agricultural or the agroforestry production systems must take into account not
only the subsistence needs of the families in terms of food, fuelwood, fodder but also some
cash incomes to meet their growing needs.
 Therefore, the development of appropriate models of Agroforestry system in a given area is
basically an interaction function of climatic, biophysical and socioeconomic factors prevalent
in the area.
 A detailed and careful study of these factors constitute the most important step in the design of agro
forestry system.

Lect - 13

ICRAF's Diagnosis and Design:

ICRAF has carried out research on agroforestry research design since its establishment. The main
objective of AFS is to optimize production and economic return per unit area especially in rural
communities. There are 3 key features in any AF research design. They are:
1. A research design in any AFS must be based on a multidisciplinary land use diagnosis so that they
are logically derives for given opportunities and constraints.
2. It should be based on socioeconomic issue because these play a part in identifying research needs
and designing appropriate methods.
3. It must base on production needs at both macro and micro levels to increase and stabilize the income
of the farmer.

DIAGNOSTIC TOOLS AND TECHNIQUES USED IN AGROFORESTRY RESEARCH

Agroforestry is a complex discipline. Hence it requires a multidisciplinary tools and techniques to

know its complexity and then focus on a specific problem. Basically there are five techniques
frequently used to tackle a complex natural resources management issue of agroforestry system. Of
the five tools mentioned below only three are practised in Nepal. Farming Systems Research has
been commonly used while carrying out on-farm trials. Most social studies have been adopting
Rapid Rural Appraisal technique for identifying problems. These tools and techniques are discussed
in brief.

1. Farming Systems Research (FRS)

2. Agro-Ecosystems Analysis (AEA)
3. Rapid Rural Appraisal (RRA)
4. Participatory Rural Appraisal (PRA)
5. Diagnosis and Design (D & D)

FARMING SYSTEMS RESEARCH (FSR)

Focusing on resource poor farmers an FSR approach seeks to adopt farm management practice, help
improve technology transfer and increase agricul-tural development.
The salient characteristics of Farming Systems Research are:
i. An applied ‗problem-solving‘ approach, conducted by multidisciplinary teams, with a degree of
farmer-participation;
ii. Assessment of the scope for, and potential impact of, technology change within a farming systems
framework;
iii. Identification of a homogenous group (usually resource-poor farmers) within specific agro-
climatic zones as clients of research;
iv. A dynamic iterative process, in which one year‘s trial results generates hypotheses for the next.

Four research categories usually fall under this system.

1. Basic (On-station, generate new understanding of biological process)
2. Strategic (On-station, solve specific research problem) 
3. Adaptive (On-farm, adjust technology to representative environment)
4. Applied (On-farm, create new technology)

The difference between on-station and on-farm research depends on the need to control variables
versus the need to test a particular technology to local conditions, working with farmers in the
process of technology development and selection. Various methodological and techniques are
conduct forr FSR. These techniques include:
1. Analysis of secondary data and exploratory surveys
2. Formal surveys and farmer monitoring
3. Laboratory tests
4. Direct observation in farmers‘ fields
5. On-farm trials

Limitations of FSR
1. Problems in multi-disciplinary collaboration, specifically interactions between social and natural
scientists;
2. Generating a ‗holistic‘ view of the farming system has led to the collection of huge, unwieldy
data-sets; FSR does not focus specifically on poor farmers;
3. Researchers dominate the design, content, conduct and evaluation of on-farm trials.

PARTICIPATORY RURAL APPRAISAL (PRA)

Participatory Rural Appraisal is a tool that helps target group or community through exercises in the
field itself. One of the essential features of this tool is that it empowers communities to make
appropriate demand on development agencies and institutions. The focus of the activity is usually
sustainable because it is conducted through local action and institutions.

Key features of PRA methodology

1. Building on villagers’ knowledge and capabilities: PRA builds on villagers‘ knowledge
through techniques such as participatory maps and models using simple materials often constructed
on the ground. The strength of this tool lies in ‗handing over the pencil or stick‘ to the villager, and
thus enabling villagers to express their capabilities.
2. Relaxed rapport: The PRA process tries to develop a relaxed rapport between outsiders and
villagers early in the process, to increase participation. This helps build the team spirit between the
outsiders and the villagers, and sustains the participatory process.
3. Diagramming and visual sharing: Using diagrams, models, maps on the ground with local
materials (sticks, stones, seeds) helps share the information being collected with a group of people;
this allows cross-checking by the group and greater participation in the analysis.
4. Sequences: Going through a series of PRA tools, such as maps, transects, and matrix ranking,
allows local people to see the interaction between different sub-systems in the village, increases their
interest in the activity and allows for greater learning and analysis. Villagers are able to use their own
Criteria in generating a local agenda and assessing priorities.
5. Training and reorientation for outsiders: PTA training is simple and can have a profound
effect on researchers, in terms of their behaviourial outlook towards villagers and learning from local
people.
PRA has been used in four major types of processes:
a. Participatory appraisal and planning;
b. Participatory implementation,
c. Monitoring and evaluation of programs;
d. Topic investigations (such as natural resources management, food security, health, etc.); and
e. Training and orientation of outsiders and villagers.

Limitations of PRA
1. Building the right team dynamics;
2. Superficial data collection, generalizing based on small sample;
3. Failure to involve all members of a community;
4. Overlooking the invisible; lecturing instead of learning and listening;
5. Imposing external ideas and values without realizing; and
6. Raising expectations in the community where the PRA is conducted regarding follow-up
activities and interventions.

Limitation of Agroforestry Research

a. Limited knowledge on the subject matter

Agroforestry research calls for multidisciplinary approach integrating forestry, livestock, animal
husbandry including sociology and anthropology. Experts on one field is not adequate enough to
conduct research on this complex discipline and hence acquire optimal output

b. Limited landholding for agroforestry development

Majority of farmers are small holders, they own limited land for crop production. Land holding is
limiting commercialization of agroforestry products

c. Absence of Agroforestry policy

There is no separate policy on agroforestry. This is somehow restricts the development of
agroforestry in the country.

d. Lack of extension materials and training opportunities

There is a need of training centres for private individuals who would like to have entrepreneurship
knowledge in agroforestry. Training should focus on skill development, market and its linkages and
optimal use of available resources, optimal use of spacing, livelihood development and enhancement

DIAGNOSIS AND DESIGN (D & D)

The D & D method was developed by John Raintree and colleagues at ICRAF, Nairobi during the
early-to-mid 1980s. It is a methodology for the diagnosis of land management problems and the
design of agroforestry solutions, and is intended to assist agroforestry researchers and development
field workers to plan and implement effective agroforestry interventions.

The basic unit of D & D analysis is the land use system and is based on the premise that knowledge
of a system (diagnosis) is essential to design effective agroforestry research for development.
 Types or Level of D&D

D & D can be used to address major decisions in land use system delineation and description,
constraints analysis, technology design and evaluation, and research planning, implementation and
analysis.
There are two types of Diagnosis and Design programme. One is ―Macro‖ and the other ‗Micro‘.
Depending on the objectives they are used in identifying the problems and designing the solution.

1. Macro D&D:

―Macro D & D‖ is a rapid appraisal technique that relies heavily on secondary data that can be verifi
ed with quick surveys. Its objective is to identify broad issues and problems constraining all Land
Use Systems in a given eco-zone. It is a large scale analysis of an eco-zone within a country or a
group of countries. Macro D&D is important for deciding on national agroforestry research and
extension agenda at the national level.

2. Micro D&D:

The objectives of ―Micro D & D‖, on the other hand, are to describe and analyse the constraints of a
given Land Use System, and then design and evaluate the agroforestry technologies, or the
appropriate research programs to develop such technologies. This focuses on one land use system
(LUS) within the larger eco-zone that has special priority for agroforestry intervention. Micro D&D
involves a detailed analysis of households and production systems in the LUS. It gives guidelines for
research that will address the constraints of the prioritized LUS.

These methodologies were of two types:

1. Procedures for holistic assessment of the constraints and problems of land use leading to
identification of specific intervention points and methods for improvement of a given land use
system and
2. Adaptation of methods and procedures those were already available for research in specific branches
of agricultural sciences, such as soil and plant sciences, to the specific conditions and needs of
agroforestry.
When the terms research and design are used together, most biological researchers in land use
disciplines immediately think of experimental designs of a statistical nature. Before thinking on such
specific experiments, however, it is necessary to determine in a holistic manner what the problems
are (in other words, to "diagnose" the problem), and what kind of research would best address the
problem. This analytical logic is the cornerstone of the "Diagnosis and Design" methodology, the
development of which represents the most significant tool for the design of agroforestry systems.

Key features of diagnosis and design:

D & D is a methodology that has been developed specifically for agroforestry applications, with
emphasis on a comprehensive diagnosis of the problems, followed by design and implementation of
appropriate interventions to solve the diagnosed problems. Its prominent features are:

 Flexibility: D & D is a discovery procedure which can be adapted to fit the needs and resources of a
wide variety of land users.
 Speed: D&D has been designed to allow for a "rapid appraisal" application at the planning stage of a
project with in depth analysis occurring during project implementation.
 Repetition: D & D is an open ended learning process. Since initial designs can almost always be
improved, the D & D process need not end until further improvements are no longer necessary.

D & D is based on the premise that, by incorporating farmers into research and extension activities,
subsequent recommendations and interventions will be more readily adopted. During the pre
diagnostic and diagnostic stages, a multidisciplinary team of researchers interacts with farmers and
 other land users either individually or in groups. These group exercises are used to characterize
current agroforestry practices, identify economic, agronomic, social, and other forms of production
constraints and discuss alternate production and management strategies. These activities are needed
to identify or elicit farmer perceptions of land use constraints. Special efforts are also made to
involve women in the diagnostic interviews. By doing so, problems such as fuel wood shortages,
which men may be unaware of or not concerned about, receive deserving attention. Farmer
interviews are also useful in initiating linkages and developing trust between farmers and
researchers, which is necessary for future program development.
If the agroforestry technologies that are envisaged in the design already exist, the D & D
methodology can be used directly as a guide for agroforestry interventions by extension workers. If,
on the other hand, the desired technologies do not exist or are not fully developed, the designs can
provide a basis for identifying the kind of research that needs to be undertaken. However, in reality,
most applications of D & D to date have been for development oriented projects.

When the terms research and design are used together, most biological researchers in land- use
disciplines immediately think of experimental designs of a statistical nature. Before embarking on
such specific experiments, however, it is necessary to determine in a holistic manner what the
problems are (in other words, to "diagnose" the problem), and what kind of research -would best
address the problem. This analytical logic is the cornerstone of the "Diagnosis and Design"
methodology, the development of which represents the most significant tool for the design of
agroforestry systems in the 1980s.
The arrangement of tree and crop components in relation to one another within plots deserves
important consideration, especially in interaction studies. Therefore, use of an appropriate design is a
very important aspect of agroforestry experimentation. A general recommendation or solution cannot
be given for all the situations since a specific problem requires a particular design.

Plot size:
The plot size is also an important consideration in agroforestry experiments. The size of the plot
depends on many factors like the objectives of the experiment, types of measurement to be made, the
expected duration of the experiment, likely ultimate size of the trees, the requirement for extra space
to avoid interference between plots etc. For example, MPT selection trials involve large number of
species or provenances and if the focus is on tree survival and growth, each species can be allocated
a small plot (20-30 m2 ). Larger plots (50-200 m ) are needed for experiments designed to test
species for particular agroforestry technologies or to study the effects of management practices.
Choosing suitable sample from which to measure the response is another important aspect of these
experiments.

Methods and tools used:

Steps in the decision-making process:

1. Decide whether agroforestry systems are appropriate:

 Describe family and community needs.
 List the needs that could be met with an agroforestry system.
 List the potential benefits, and their relative importance, of an agroforestry system in the region in
question.
 Find the limiting constraints in agriculture, including markets and marketing.
 Consider whether the people of the region are willing or capable of adopting a system.
 Then decide if it is worth the effort to develop one.

2. Design a system:
 Select the area.
 Characterize its strengths and weaknesses with respect to existing soil, water, and crops.
 Select the trees, shrubs, or grasses to be used (give preference to locally adapted plants)
 Characterize the minimum space requirements, water and fertilizer needs, and shade tolerance of the
 desired crops.
Further decisions as influenced by anticipated duration of the system
a. If the system is temporary:
 Plan the features of soil erosion control, earthworks, and gully maintenance first.
 Plan spacing of fruit trees according to final spacing requirements.
 Plan a succession of annual or short-lived perennials, selecting the most shade tolerant crops for the
final years of intercropping.
b. If the system is permanent:
 Plan the proportion of the permanent fruit and lumber trees on the basis of relative importance to the
farmer.
 Plan the spacing of long-term trees on the basis of final space requirements.
 Plan succession of annual and perennial understory crops, including crops for soil protection and
enrichment.
 As large permanent trees grow, adjust planting plan to place shade tolerant crops in most shady
areas.
c. With both temporary and permanent systems:
 Always keep the ground covered using various crops to protect soil from sun and erosion (wind, rain,
animals).
 Try the system on a small scale first.
 Measure the inputs and outputs of the system.
 Evaluate whether the benefits expected have been achieved.
 Expand or extend any new system cautiously. Top of document

3. Process of Designs and analysis in agroforestry systems:

Use of an appropriate design is a very important aspect of agroforestry experimentation. Several
characteristics of the trees like slow growth, long term effects on their surroundings, long life, age of
trees, the area over which the influence of trees extend etc. complicate the issue of designing
experiments for these systems. So, a general recommendation or solution cannot be given for all the
situations. In addition to the basic principles i.e. randomization, replication and local control, there
are several other factors that need to be taken care of while planning agroforestry experiments. For
example, within one experimental plot there may be crop rows, individual trees or hedges with
different treatments applied to each and each component may respond to its own treatment as well as
to the treatments applied to other components.

The Diagnosis & Design process follows five stages:

A. Pre-diagnostic,
B. Diagnostic,
C. Design and evaluation,
D. Panning and
E. Implementation.
 Fig: D & D is an Interactive Process

The basic logic of the procedure put forward by ICRAF (1987) is presented in Table, which
summarizes the basic questions, key factors and modes of inquiry regarding the different stages.

Table . Basic procedures and stages of D & D

D & D stages Basic questions to Key factors to consider Mode of inquiry
answers
Diagnostic Which system to focus Distinctive combinations Setting and comparing the
on? of resources, technology different land use system
and land user objective Analyzing and describing
How is it organized? Production objectives and the system
How does it function to strategies, arrangement of
achieve its objectives? components
Design & What is needed to Specifications for problem Diagnostic interviews and
Evaluation improve system solving or performance direct field observations
performance? enhancing Interventions Troubleshooting the
problem subsystem
Planning What to do to develop Research and Research design project
and disseminate the development needs planning
improved system? extension needs
Implementation How to adjust to new Feedback from on-station Re diagnosis and redesign
information? research, on farm trials in the light of new
and special studies information

Limitation of D & D
There appears to be some potential limitations to this method. These include:
 Tendency to focus on agroferestry technologies only;
 Process may be driven by external researchers; and
 Macro D & D requires a large amount of secondary a data and time
Assignments:
1. What are the techniques and tools of AFS? Give the key feature and basic process of D & D.
2. What are the criteria of selecting AFS designing and its affecting factors?
 Lect -14 & 15

MANAGEMENT OF TREES IN AGROFORESTRY

Introduction:
Agroforestry systems involve the interaction of trees with crops, livestock or both. Such a situation
needs judicial management of trees, animals and crops. The effective and efficient agroforestry
management practices are divided into two groups.
1. Tree management and
2. Agriculture management

Management of Trees in Agroforestry:

The management of trees in agroforestry systems includes various practices that are required to get
desired product from the unit area. The tree management practices should be carried out by farmers
to get desirable product, properly manage the tree canopy and roots in order to facilitate maximum
resource utilization, management of organic residues for nutrient cycling, proper method of
harvesting tree as well non-timber tree products, protection from biotic and abiotic stresses.
The main objective of tree management is to minimize the negative tree-crop interactions and
maximize the positive. The type of tree management practices depend mainly on the characteristics
of the species and the purpose for which it is grown. Broadly these management practices can be
categorized as : aboveground and belowground management.

1. Aboveground Management
The aboveground management practices include pruning, thinning, pollarding, lopping
and coppicing.

1.1. Pruning
Pruning is the practice of managing perennial tree species by cutting away dead or overgrown
branches as per the requirement of crop and tree growth. Pruning is synonymously used and reported
as pollarding, coppicing or lopping based on pruning intensity and place of pruning (height).
Coppicing is the most extreme of the tree cutting practices, usually involving cutting to a height of
10-30 cm above ground. Lopping, cutting off branches, commonly leaves stubs of about 30-100 cm
long on 150-200 cm main stems

Tree Pruning Tips

The following tips and techniques will help guide you if you‘re planning on pruning a tree or if you
just want to educate yourself about typical tree trimming care and maintenance techniques.

Crown Thinning

If you need to thin the crown of a tree, you should keep the following tips and techniques in mind:

 Keep lateral branches as evenly spaced as possible, especially on young trees.

 Prune away branches that cross other branches or run against them.
 Never remove more than one-fourth of a living crown at once. If you need to remove
more than that, spread it out over a number of years.
Crown Raising

 To provide clearance for pedestrians and for other reasons, you can raise the crown by
carefully pruning the tree. Maintain live branches on at least two-thirds of a tree’s height.
If you remove too many branches near the bottom half, the tree may not be able to develop a
strong stem.

Crown Reduction

 If you need to remove more than half of the foliage from a branch, just remove the whole
branch.
 Only reduce the crown of a tree if it‘s really necessary. Prune lateral branches that are at least
one-third of the diameter of the stem that needs to be removed.
The main purposes of the pruning are:
To restore the functional balance between above - and below-ground plant organs by reducing root
respiration, slowing or ceasing root growth or reallocating carbon from storage organs in roots and
stems to shoot meristems to support tree regrowth.
To reduce the competition between tree and crops for light, water and nutrients.
To train trees to a single straight stem and develop more valuable, knot-free trunks.
To increases the growth rate of the branches left after pruning.
To create a healthy, structurally sound tree with good branch architecture.
Maintain a strong central leader to obtain a longer merchantable log to increase the value of the tree.
Suppression or removal of lower limbs, or vigorous branches that are growing upward into the
canopy. No more than 25 to 30 per cent of the foliage should be removed in any year, especially if a
tree is mature.

1.2. Thinning
As a plantation matures, trees become crowded and competition among trees causes growth rates to
decline. A dense stand initially promotes straight growth and small branches, but later the trees must
be removed; otherwise, they will grow too slender and eventually not reach the desired size. This
selective process of removing or killing some trees to allow the remaining trees to maintain a steady
growth rate, is called thinning

The purposes of thinning in agroforestry systems are :

To obtain firewood and wood for construction purpose in earlier years of plantation.
To selectively remove poorly formed trees and species of lower value.
To provide suitable light conditions to the crop and to eliminate the excess root competition
between the trees and crops.
To get earlier return by selling small poles and fuelwood.
Maintain a strong central leader to obtain a longer merchantable log to increase the value of the tree.
Suppression or removal of lower limbs, or vigorous branches that are growing upward into the
canopy. No more than 25 to 30 per cent of the foliage should be removed in any year, especially if a
tree is mature.

1.3. Pollarding
Pollarding is a process in which crown of the trees are cut at least 2 m above the ground level i.e.
beyond the reach of cattle, in order to get flush of new shoots is the repeated pruning of branches at
or near the same point, which results in a distinctive thick bushy appearance of the trees (Soule,
1985). Typically, depending on pruning height and the needs of associated crops, pollarding allows a
time window of 3-4 months where there is negligible competition for light between crops and trees.
However, fine roots and nodules start to regrow after 2-3 months after pruning and competition for
nutrients may occur.

The objectives of pollarding are :

Early harvest of wood, fodder or other biomass.
Production of wood or fodder at heights that is out of the reach of livestock, hence there is no need
for protection from browsing.
Reduction of shading of nearby crops.
Regeneration of the tree crown to promote growth of the trunk for timber or small poles, withies for
construction and wicker handicrafts.

The choice of pollarding height and frequency depends on the desired products. If the main aim is to
produce timber or poles, the top of the tree should be cut as high up as possible, and the pollarding
interval should be such that the crown is kept as green and vigorous as possible for the maximum
production of trunk wood. An interval of 2 to 5 years is appropriate in such cases. Sometimes the
main aim is to produce staking material, poles or withies for construction. In such situations a wide
stool will allow many stems to grow.

1.4. Lopping
Lopping is the cutting off tree branches e.g. mainly of leafy branches or twigs from a tree. The time
window for renewal of inter specific competition for light is similar to trees managed by pollarding
but may be less depending on branch taxonomy for carbon uptake.

The objectives of lopping are given below :

To meets seasonal needs for food, fodder, fuelwood and other subsistence requirements.
To encourage new flush of growth.
To maintain the hygiene of the trees.

1.5. Coppicing
Many species of trees and shrubs have the ability to re-sprout after the whole tree has been cut. If this
ability is utilized for regeneration of the tree and this practice is known as coppicing. Coppicing can
almost be regarded as a method of tree propagation since it can substitute for the task of planting a
new tree after a mature one is felled. This practice involves cutting the tree down to the stump and
allowing it to re-grow to maximize biomass production. Copping provides longer time window (4-6
months depending on species) in which there is negligible competition for light between coppiced
trees and crop(s).

The purposes of the coppicing are delineated below :

To create a multi-stemmed shrub rather than a large single-trunked tree
To rejuvenate old trees and generates new vigorous stems
To encourage larger leaves on trees
To generate woody stems for firewood and/or charcoal making

The optimum cutting height for most of the coppicing trees should be kept in between 30-50 cm
above the ground level. The coppice should be carried out while trees are dormant.

1.6 Weeding
Weeding is an important tending operation. Especially in plantations, weeding has to be carried out
at least twice a year: once immediately after plantations and next in winter period. Results have
shown that weeding has a remarkable effect on the height and diameter growth especially in case of
Eucalyptus species.

1.7 Harvesting age

Farmers‘ tend to harvest trees as and when necessary. Harvesting age of trees varies depending on
the objectives of plantation. In Terai belts of the country people in general harvest trees especially
for firewood.

1.8 Pest and Disease

Diseases may also occur during agroforestry plantation establishment. It should be noted that trees of
varied ages may be affected by fungal pathogens and insect pest.

2. Belowground Management
The management of belowground interactions is most important where trees and crops are grown in
close proximity and where soil resources (water, nutrients) are limiting, as in seasonally dry climates
and semi-arid tropics. Below ground competition is minimized by selecting trees of less competitive
root architecture or deep root system. Tree management, rather than species selection, is an attractive
approach because it allows farmers to grow the tree species they want, rather than those with
particular root architecture. Main belowground management practice is root pruning.
 2.1. Root Pruning
Tree root pruning is a potential tool for managing belowground competition when trees and crops are
grown together in agroforestry systems. The tree roots are managed by trench and artificial root
barriers. Root pruning, usually by way of trenching, has been used as a mean to separate root systems
of trees and crops, thereby reducing belowground competition significantly. Drawback of this system
is increase in root density and root mass near the pruned area which causes soil moisture stress.
Therefore, periodic root pruning is suitable and minimizes moisture depletion problem but it is
labour intensive. Another quick method is tractor drawn disc ploughing. Deep disc ploughing to a
depth of 60-90 cm in between the tree lines helps to cut down roots and minimize the root growth. It
is less labour intensive
Trees growing in cropland can have their shallow roots cut 0.3 to 0.6 m from the trunk when they
reach a height of 2 to 3 m. This is applicable to species that would otherwise compete with crops for
resources like moisture and nutrients (Lwakuba et al., 2003). The roots are best managed by digging
a relatively deep trench (0.3-0.6 m) along the edges of woodlots, for example, Acacia mearnsii,
where the woodlots border cultivated land. The trench serves to minimize competition underground
competition between crops and trees for nutrients and water. An obvious disadvantage of all
techniques for root management is that they require a lot of work

Agricultural and Silvicultural Management in Relation to Crop;

Agriculture is the science, art and practice of cultivating plants and livestock. Agriculture was the
key development in the rise of sedentary human civilization, whereby farming of domesticated
species created food surpluses that enabled people to live in cities.
Silviculture is the practice of controlling the growth, composition/structure, and quality of forests to
meet values and needs, specifically timber production.
The name comes from the Latin silvi- ("forest") and culture ("growing"). The study of forests and
woods is termed silvology. Silviculture also focuses on making sure that the treatment(s) of forest
stands are used to conserve and improve their productivity.
Generally, silviculture is the science and art of growing and cultivating forest crops, based on a
knowledge of silvics (the study of the life-history and general characteristics of forest trees and
stands, with particular reference to local/regional factors). In specific, silviculture is the practice of
controlling the establishment and management of forest stands.
The distinction between forestry and silviculture is that, silviculture is applied at the stand-level,
while forestry is a broader concept. Adaptive management is common in silviculture, while forestry
can include natural/conserved land without stand-level management and treatments being applied.
Agricultural production within an AFs may take many forms such as pasture for grazing,
horticultural crops, apiculture, fish, poultry, agricultural crops, cash crops, forage crops, for
harvesting or any combination of these. Agricultural management is highly varied due to the
changing nature of the systems. It is divided into the following stages on the basis of tree growth and
management.

1. Pre-planting phase
2. Establishment phase (From planting to the time of first pruning/thinning)
3. Silvicultural management phase (during which all the thinning and pruning is done)
4. Maturing phase (During which the trees are left virtually unattended until they reach
maturity)
5. Harvesting phase

1. Pre-Planting phase:
This phase consists of adequate site preparation, improvement of soil fertility, and weed control. In
this phase the site is prepared and fertility of the site is increased by growing one or two agricultural
 crops before planting trees. Emphasis for N-fifing trees will improve more soil structure and fertility.

2. Establishment phase:
In this phase of management, young trees are carefully tended until they are large enough tofond for
themselves. (In this phase hay or silage crops are more suitable to grow in between the rows of trees
and cut in short time. The crops should not grow close to the base of the trees as this will encourage
competition which may affect the tree growth during its establishment phase.

3. Cropping between young trees:

Appropriately managed tree plantings allow considerable agro crops production in between tree
rows. How close agricultural crops can be grown to trees without inducing excessive competition
depends on the rooting habits of both trees and crops. In general one meter wide free zone should be
left on either side of the tree rows to encourage early tree growth.

4. Silvicultural management phase:

During this phase of tree development it is important to consider doing the thinning and pruning in
such a way as to minimize the effect on agricultural production. By the age of first thinning and
pruning operations, the tree begin compete with agricultural crops. Light is the most limiting factor
to affect agro crops. This completion makes cropping inefficient due to reduced returns from the
same area. Livestock, apiculture will be an ideal option in this matter light pruning is desirable then
heavy pruning. Pruning should be done during winter months to minimize the attack of pathogens.

5. Maturing phase:
In this phase of management, different practices are involved beneath the maturing trees such as
grazing, maintenance of soil moisture and fertility, and weed controls which improve the aesthetic
value of the stand.

6. Harvesting phase:
This phase involves harvesting of tree crops. Harvesting of timber from agro forestry can begin as
soon as the trees become large enough to allow a profitable sale. The optimum time of harvest
depends on three factors as:
 Value of the standing timber and its expected increase in value over time.
 Availability of suitable market
 Owners' interest

Assignments
1. What are the techniques of tree management in AFS? Why it is important?
2. What are the stages of Agriculture management systems? What will be the consequences if not
manage?

Terms used in Agroforestry:

Gradient: By the term gradient mean slope. The gradient is expressed by stating how far you must
travel is rise to a given height.

Gradient = Vertical interval / horizontal equivalent

= 300/ 1500 = 1/5 i.e. 1 in 5
Where, 300 m
(1= height, asl, m)
(5= distance travelled, m)
1500 m
 Social forestry: The use of tree to pursue social objectives, usually the betterment of poor. Open
vegetation: Crowns or shoots not touching to each other.
 Flora: It is the total list of plant species present irrespective of abundance of each species.
 Vegetation: It is the collective plant life of an area or the combination of species present and
their relative abundance.
 Dominant tree: Trees which form the uppermost canopy and have their leading shoots free.
 Co-dominant tree: Together with dominant, they form the main canopy but they are not quite as
tall as dominants. Their height is about 5/6 that of dominant.
 Dominated trees: Trees which do not form part of the uppermost canopy but the leading shoots
of which are not overtopped by the neighboring trees. Their height is about 3/4 that of dominants.
 Suppressed: The trees whose leading shoots are either overtopped by their neighbors or shaded
on all sides by them. They reach only 54 to 5/8 of the height of dominant.
 Speciation: The process by which new species is formed.
 Branched speciation: It is the process by which a single species branches down to form two or
more new species.
 Gradualism: It is the process by which a\ species changes gradually over time.
 Commensalism: It is a condition in which one population benefits another, but is not itself
significantly affected by the interaction. Orchids grow on trees, the former are benefitted while
the latter are not seriously affected.
 Natasity: The rate at which new members are added to the population by reproduction.
 Dispersal: The rate at which individuals immigrate into the population and emigrate out of the
population. This attribute applies mostly to animals.
 Population growth rate: It is the combined effect of natural mortality and dispersal on
population.
 Agrosilvicultural system: An agroforestry system for the concurrent production of agro crops
and forest crops. Here the trees offer productive and service roles.
 Apisilvicultural system: An agroforestry system in which honey bee colonies are integrated with
agro crops and woody perennials.
 Apihortipastoral system: An agro forestry system for the production of fruits, honey and meat.
 Agropastoral system: A farming system in which crops and livestock are integrated with woody
perennials.
 Bush fallow: A fallow of usually 3 to 10 years in which the natural vegetation which regenerates
is composed, principally of shrubs and young trees.
 Seedling: From germination to attainment of a height of one meter.
 Sapling: After attaining the height of one meter to the stage when its lower branches begin to
fall.
 Pole: From the stage of falling of the lower branches to the time when the rate of increase in
height begin to fall and the crown begin to expand significantly.
 Forest: All lands bearing vegetative associations dominated by trees of any size, exploited or not,
capable of producing wood or of exerting an influence on the local climate or on water regime or
providing shelter for livestock and wildlife. -FAO.
 Zero grazing: Livestock production systems in which the animals are fed in pens or other
confined area and are not allowed to open graze.
 Share cropping: The exchange of land use rights for a fixed percentage of the harvest.
 Rotational grazing: Grazing system in which the pasture is subdivided into a number of
enclosures with at least one more enclosure than group of animals.
 Rangelands: Those area of the world which by reason of physical limitation, low and erratic
precipitation, rough topography, poor drainage or cold temperatures are unsuited for cultivation
and which are a source of forage for free grazing native and domestic animals as well as a source
of wood production, water and wildlife.
 Protective plants: Plants grown to protect crops, soil or land from adverse environmental factors.
 Pasture reseeding: Rehabilitation of an existing pasture which has become too sparse to offer
effective soil cover. It provides denser stand.
 Niches: Specific physical places in the landscape.
 Monoculture: Repeated growing of the same crop on the same land.
 Ley farming: Rotation of arable crops with two or more years of sown pasture.
 Grass stripes: Bands of grass either natural or planted on unploughed land along the contour
between stripes of cropped land to reduce erosion.
 Telescoping measuring rod: Instrument to measure tree height up to 12 to 15m. It can be read
from eye level making it easier and faster to use than fixed rods.
 Fixed measuring pole: This is made of bamboos or round wood and can be used on trees up to
6m in height.
 Hyprometer /clinometers: Instruments used to measure tree heights.
 Caliper: It is often used for measuring diameter.
 Diameter tape: This gives the diameter of an angle by using the formula d= circumference divide by
π.
 Sprouts: Shoots growing out of the stump or roots.
 Phenology: The study of the seasonal timing of the life events of an organism.
 Multipurpose Tree Species (MPTS): Tree species purposely grown to provide more than one
significant product/or service function in the land use systems they occupy.
 Lopping: Cutting off one or more branches of tree, whether standing, felled or fallen.
 Border: Region of a plot surrounding the measured part of the experimental plot.
 Biomass: For MPTS, the total weight at given time of living trees or tree part per unit area.
 Regeneration felling: A felling made to stimulating regeneration under a shelter wood system.
Includes seeding felling, secondary felling, and final felling.
 Shelter wood felling: Includes seedling felling, secondary felling and final felling.
 Seeding felling: Opening the canopy of a mat stand to provide conditions for securing
regeneration from the seed of trees retained for that purpose. The first stage of regeneration
felling under a shelter wood system.
 Secondary felling: A regeneration feeling carried out between the seeding feeling and the final
felling under a shelter wood system in order gradually to remove the shelter and admit increasing
light to regenerated crop.
 Final felling: The removal of the last seed or shelter trees after regeneration under a shelter wood
 system. The final stage in regeneration fellings.
 Regeneration interval: The interval between the seeding felling and the final felling on a
particular area under one of the shelter wood systems.
 Felling cycle: The time which elapses between successive main feelings on the same area.
 High forest systems: Those silvicultural systems in which the regeneration is normally of
seeding origin either natural or artificial.
 Clear feeling systems: Clear feeling systems are those silviculturaal systems in which the
matured crop is removed in one operation.
 Shelter wood system: Those silvicultural systems in which the matured crops are removed in a
series of operations, the first of which is the seeding felling and the last is the final felling. Other
feelings if any are called secondary felling.
 Coupe: A felling area, usually, one of an annual series unless otherwise stated. Preferably,
numbered with Roman number, I, II, III etc.
 Normal series of age gradation: A complete series of age gradation (i.e. an age class with one
year interval) from seedling to the mature stage.
 Deforestation: The permanent clear felling of an area of forest or woodland. This can lead to
sever soil erosion due to the sudden heavy flow of water, especially were heavy seasonable rains
or the melting of snow happens at higher levels.
 Coppice stump: The removal of a tree that has been cut usually to or near the ground level and
from which coppice growth develops.
 Coppice - with standards: A coppice system in which trees are allowed to grow to their fuel
height (standard) for use as structural timber.
 Coppice shoot: A shoot that arise from a bud at the base of the shoot of a tree that has been cut
near the ground.
 Advance growth: Seedlings, saplings and poles of species of over wood that have become
established naturally in a forest before regeneration fellings are started.
 Afforest ration: Establishing a forest by artificial means on an area from which forest vegetation
has always or long been absent.
 Exploitable age: The age at which individual tree or crop attains the size or stage of growth
required to fulfill the objects of management.
 Bole: The main stem of a tree. Sometimes used to refer to only the lower part of the stem up to a
point where the main branches are given off.
 Boom: A contrivance/device, usually of linked floating timber, for arresting the passage of timber
floated down a river from the point or its upper reaches or in coastal depots for preventing the
escape of timber due to tidal currents.
 Grove: a. A small wood usually of less than eight hectare, b. An area that is composed entirely of
timber trees without under wood within a large woodland.
 Growth form: The morphology of a tree especially as it reflects physiological adaptation to the
environment.
 Biodiversity: A term which gained popularity in the late 1980 that describes of biological
diversity, especially including species richness, ecosystem complexity and genetic variation.
  Butt: The base of a tree or lower end of a log.
 Carrying capacity: The maximum population of a given organism that a particular environment
can sustain.
 Boundary Plantings: Trees planted along boundaries or property lines to mark them well.
 Dispersed Trees: Trees planted alone or in small numbers on pastures or otherwise treeless
areas.
 Improved Fallows: Areas left to grow up selected trees in trees-crop rotation systems.
 Individual Trees: Trees occurring alone, whether spontaneously emerging or planted.
 Living Fences: Fences in which the posts are living trees, or in which the entire fence consists of
closely-spaced trees or shrubs.
 Nectar Crops: Trees valuable as a source of nectar for honey bees.
 Pollen Crops: Trees which provide pollen for honey bees.
 Propolis tree: Trees from where honey bees collect propolis
 Entomophily Plants: Plants in which pollination is done by insects
 Terraces: Level areas constructed along the contours of hills, often but not necessarily planted
with trees
 Vegetative: Long, narrow areas of any vegetation, usually planted along contours for erosion
control; may include trees
 Woodlot: An area planted to trees for fuel or timber
 Quarter girth: The girth of a tree or log divided by four
 Log: The steam of a tree or a length of the stem
Related Glossary
Adaptation—Adjustment in a natural or human system in response to actual or expected climatic
stimuli or their effects that moderates harm or exploits beneficial opportunities.

Adaptive capacity—The ability of a system to adjust to climate change (including climate

variability and extremes), to moderate potential damages, to take advantage of opportunities, or to
cope with the consequences.

Adaptive management—A decision process that promotes flexible decisionmaking that can be
adjusted in the face of uncertainties as outcomes from management actions and other events become
better understood. Careful monitoring of these outcomes both advances scientific understanding and
helps adjust policies or operations as part of an iterative learning process.

Afforestation—Direct human-induced conversion of land that historically has not been forested to
forested land through planting, seeding, and/or the human-induced promotion of natural seed
sources. Most agroforestry plantings in temperate regions do not meet the definition of forest based
on size criteria. As such, they do not qualify as afforestation practices, although ecologically they are
afforestation like in their growth and ecological behavior.

Agro-deforestation—The process of destroying or neglecting the traditional agroforestry systems in

favor of plantation-type agriculture.

Aagroforestry—Intensive land-use management that optimizes the benefits (physical, biological,

ecological, economic, and social) from biophysical interactions created when trees and/or shrubs are
deliberately combined with crops and/or livestock.
Agroforestry practice—A category of agroforestry based on the type and purpose of the planting.
The five categories of agroforestry practices recognized in the United States and Canada include
windbreaks, riparian forest buffers, alley cropping, forest farming, and silvopasture, with a growing
sixth category to capture modifications of the five practices for use in addressing emerging issues
(e.g., stormwater treatment, biofeedstock production).

Aagroforestry system—A land-use management system in which woody perennials (trees, shrubs,
bamboos, palm trees, woody lianas) are grown on the same land management unit with crops and/or
livestock to create interactions considered beneficial to the producer and/or the land. An agroforestry
system can be subdivided into other systems and is a part of larger systems.

Alley cropping—The planting of trees or shrubs in two or more sets of single or multiple rows with
agronomic, horticultural, or forage crops cultivated in the alleys between the rows of woody plants.

Biodiversity—The variability among living organisms from all sources, including within species,
among species, and of ecosystems.

Bio-energy—Any renewable energy made from biological sources. Fossil fuels are not counted
because, even though they were once biological, they are long dead and have undergone extensive
modification.
Bio-fuel—Any liquid, gaseous, or solid fuel produced from biofeedstock.

Biological corridor—Geographic track that allows for the exchange and migration of species within
one or more ecosystems. Its function is to maintain connectivity of biological processes to avoid the
isolation of species populations.

Biological pest control—The beneficial action of predators, parasites, pathogens, and competitors in
controlling pests and their damage. Biological control provided by these living organisms (―natural
enemies‖) is especially important for reducing the number of pest insects and mites.

Biomass—The total mass of living organisms in a given area or volume; recently dead plant material
is often included as dead biomass. The quantity of biomass is expressed as a dry weight or as the
energy, carbon, or nitrogen content.

Carbon allocation—The distribution of carbon within the various components of an entity of

concern (i.e., from a single tree to the whole ecosystem of which that tree may be part). In the case of
this report, carbon allocation refers to the apportionment or distribution of carbon in the various
components of the plants and soil system.

Carbon dioxide (CO2 )—A naturally occurring gas, fixed by photosynthesis into organic matter and
also a byproduct of burning fossil fuels and biomass, land-use changes, and other industrial
processes. It is the principal anthropogenic greenhouse gas that affects the Earth‘s radiative balance.
It is the reference gas against which other greenhouse gases are measured and, therefore, has a global
warming potential, or GWP, of 1.

Carbon equivalent—A quantity that describes, for a given mixture of greenhouse gas (GHG), the
amount of carbon dioxide (CO2 ) that would have the same global warming potential (GWP) when
measured over a specified timescale (in general, 100 years). The GWPs of the three GHGs associated
with forestry are as follows:
(1) CO2 persists in the atmosphere for about 200 to 450 years and its GWP is defined as 1,
(2) methane persists for 9 to 15 years and has a GWP of 25 (meaning that is has 25 times the
warming ability of carbon dioxide), and
(3) nitrous oxide persists for about 120 years and has a GWP of 310.
Carbon flux—The rate at which carbon moves to or from a particular component of an ecosystem
per unit ground area per unit time.

Carbon footprint—The total amount of greenhouse gases that are emitted into the atmosphere each
year by a person, family, building, organization, or company.

Carbon sequestration—The processes that remove carbon dioxide (CO2 ) from the atmosphere.
Terrestrial or biological carbon sequestration is the process by which plants absorb CO2 , release the
oxygen, and store the carbon. Geologic sequestration is one step in the process of carbon capture and
sequestration and involves injecting CO2 deep underground where it stays permanently.

Carbon sink—Any process, activity, or mechanism that removes carbon dioxide from the
atmosphere. Carbon sinks include the oceans, plants, and other organisms that remove carbon from
the atmosphere via photosynthetic processes.
Carbon stock—The quantity of carbon held within a pool at a specified time.

Chilling requirement—The minimum period of cold weather after which a fruit- or nut-bearing tree
will break dormancy and begin flowering.

Climate—In a narrow sense, the average weather or, more rigorously, the statistical description in
terms of the mean and variability of relevant quantities over a period of time ranging from months to
thousands or millions of years. The classical period is 30 years, as defined by the World
Meteorological Organization. The relevant quantities are most often surface variables such as
temperature, precipitation, and wind. In a wider sense, the state, including a statistical description, of
the climate system.

Climate change—A statistically significant variation in either the mean state of the climate or in its
variability, persisting for an extended period (typically decades or longer). Climate change may be
due to natural internal processes or external forcings, or it may be due to persistent anthropogenic
changes in the composition of the atmosphere or in land use. Note that Article 1 of the United
Nations Framework Convention on Climate Change (UNFCCC), defines climate change as ―…a
change of climate which is attributed directly or indirectly to human activity that alters the
composition of the global atmosphere and which is in addition to natural climate variability observed
over comparable time periods.‖ The UNFCCC thus makes a distinction between climate change
attributable to human activities altering the atmospheric composition and climate variability
attributable to natural causes.

Climate change adaptation—The efforts by society or ecosystems to prepare for or adjust to the
changes in climate.

Climate change mitigation—Human intervention to reduce the human impact on the climate
system, including strategies to reduce greenhouse gas (GHG) sources and emissions and to enhance
GHG sinks. See also mitigation.

Climate smart agriculture—An approach to developing the technical, policy, and investment
conditions to achieve sustainable agricultural development for food security under climate change.

Climate variability—Variations in the mean state and other statistics (such as standard deviations,
the occurrence of extremes) of the climate on all temporal and spatial scales beyond that of
individual weather events. Variability may be due to natural internal processes within the climate
system (internal variability) or to variations in natural or anthropogenic external forcing (external
variability).
Cultivar—A contraction of ―cultivated variety,‖ referring to a plant type within a particular
cultivated species that is distinguished by one or more characters.
Ecosystem service—An ecological process or function having monetary or nonmonetary value to
individuals or society at large. Ecosystems services are
(1) supporting services, such as productivity or biodiversity maintenance;
(2) provisioning services, such as food, fiber, or fish;
(3) regulating services, such as climate regulation or carbon sequestration; and
(4) cultural services, such as tourism or spiritual and aesthetic appreciation.

Enterprise budget—A financial management tool to estimate the costs and receipts (income)
associated with the production of a specific agricultural product.

Evapotranspiration—The sum of evaporation and plant transpiration. Evaporation accounts for the
movement of water to the air from sources such as the soil, canopy interception, and water bodies.
Transpiration accounts for the movement of water within a plant and the subsequent loss of water as
vapor through stomata in its leaves.
First Nations—The aboriginal groups formally recognized by the Canadian Government under the
Federal Indian Act of 1876.

Food security—A situation that exists when people have secure access to sufficient amounts of safe
and nutritious food for normal growth, development, and an active and healthy life. Food insecurity
may be caused by the unavailability of food, insufficient purchasing power, inappropriate
distribution, or inadequate use of food at the household level.

Forest farming—The intentional cultivation of edible, medicinal, or decorative specialty crops

beneath native or planted woodlands that are managed for both wood and understory crop
production. Forest farming does not include the gathering of naturally occurring plants from native
forests, also known as wildcrafting.

Greenhouse gas (GHG)—Any gas whose absorption of solar radiation is responsible for the
greenhouse (warming) effect. Some GHGs, such as carbon dioxide (CO2 ), may be emitted or drawn
from the atmosphere through natural processes or human activities. Other GHGs, such as certain
fluorinated gaseous compounds, are created and emitted solely through human activities. The
principal GHGs that enter the atmosphere because of human activities are CO2 , water vapor,
methane, and nitrogen oxide and also fluorinated gases, such as hydrofluorocarbons, per-fluoro-
carbons, and sulfur hexafluoride.
Greenhouse gas mitigation—A human intervention to reduce the human impact on the climate
system, including strategies to reduce greenhouse gas (GHG) sources and emissions and to enhance
GHG sinks.

Home garden—A private-property garden around a house that contains various trees, crops, and
animals. Homegardens exist more in tropical areas than in cooler climates.

Intercropping system—The growing of two or more different species of crops simultaneously, as in

alternate rows in the same field or single tract of land.

Living fence—Rows of living plants, such as grasses, shrubs, and trees, that are strategically planted
to work as a structural barrier.

Methane emission—The production and discharge of methane (CH4 ) that occur by natural sources
such as wetlands and also by human activities such as leakage from natural gas systems and the
raising of livestock. Agricultural emissions of CH4 are caused when domestic livestock such as
cattle, buffalo, sheep, goats, and camels produce large amounts of CH4 as part of their normal
digestive process.
Microclimate—The local climate of a given site or habitat varying in size from a tiny crevice to a
large land area, but being usually characterized by considerable uniformity of climate over the site
involved and relatively local compared with its enveloping macroclimate from which it differs
because of local climatic factors (such as elevation and exposure).

Multifunctional agriculture—The practice of farming that produces various noncommodity outputs

in addition to food.

Nitrous oxide emission—The production and discharge of nitrous oxide (N2 O) that occur naturally
through many sources associated with the nitrogen cycle, which is the natural circulation of nitrogen
among the atmosphere, plants, animals, and microorganisms that live in soil and water. Agricultural
emissions of N2 O are caused when people add nitrogen to the soil through the use of synthetic
fertilizers.

Forest products—Goods harvested from woodlands, including herbal plants like ginseng and
goldenseal, specialty mushrooms like shiitake and reishi, and wild foods.

Resiliency—The ability of a social or ecological system to absorb disturbances while retaining the
same basic structure and ways of functioning, the capacity for self-organization, and the capacity to
adapt to stress and change.

Riparian forest buffers—An area of trees, shrubs, and herbaceous vegetation established and/or
managed adjacent to streams, lakes, ponds, and wetlands.

Shelterbelt—A single row or multiple rows of trees and possibly shrubs planted in a linear fashion
and established upwind of the areas to be protected. Although this term is more often used
interchangeably with windbreaks, some use this term to designate thicker (i.e., more plant rows)
plantings to provide protection to farmsteads and livestock.

Silvopasture—The intentional combination of trees, forage plants, and livestock in an integrated,

intensively managed system.

Soil organic carbon—The carbon occurring in the soil in soil organic matter, a term used to
describe the organic constituents in the soil (tissue from dead plants and animals, products produced
as these decompose, and the soil microbial biomass).

Subsurface tile drain—A conduit installed beneath the ground surface to collect and/or convey
subsurface drainage water.

Taungya—A Burmese word that is now widely used to describe the agroforestry practice, in many
tropical countries, of establishing tree plantations by planting and tending tree seedlings together
with food crops. Food cropping is ended after 1 to 2 years as the trees grow.

Uncertainty—An expression of the degree to which a value (e.g., the future state of the climate
system) is unknown.

Vulnerability—The degree to which a system is susceptible to, or unable to cope with, adverse
effects of climate and global change, including climate variability and extremes.

Weather—The specific condition of the atmosphere at a particular place and time. Weather is
measured in terms of parameters such as wind, temperature, humidity, atmospheric pressure,
cloudiness, and precipitation.

Windbreak—A single row or multiple rows of trees or shrubs that are established for environmental
purposes.
 Some of the multipurpose agroforestry species in land use systems of Nepal
Fodder Trees
Local name Botanical name Uses Suitable area
Badahar Artocarpuslakoocha fuel fruit Others Terai and mid
hills
Moka Acacia modesta fuel Teraimidhills
Babul Acacia vllosa fuel timber Terai, lower
midhills
Dabdabe GarugaPinnatar fuel nectar , pollen
IpilIpil Leucaena spp. fuel soil Terai, midills
conservation
Kabro Ficuslacor fuel soil pickle Terai,
conservation midhills
Khanyu Ficus fuel fruit Terai,
semicordata midhills
Khasreto Ficushispida fuel Terai,
midhills
Kimbu Morus alba fuel sericulture Terai,lowermid
hills
Churi Aesandra fuel Timber, fruit nectar Midhills,
butyracea
Koiralo Bauhinia fuel pickle nectar, Terai, mid hills
Bauhinia variegata pollen
variegata
RaharCajanus Cajanuscajan fuel food Terai,
cajan midhills
KutmeroLitse Litsea fuel Terai, mid hills
amonopetala monopetala
TankiBauhini Bauhinia fuel nectar, Terai, mid hills
a purpurea purpurea pollen
Nimaro Ficusroxburghii fuel Terai, mid hills
Pakhuri Ficusglaberrima fuel Terai to higher
hills
Fuel wood/Timber trees
Bakaino Meliaazedarach fodder Terai, mid
hills
Sal Shorearobusta fodder nectar,polle Terai, mid
n hills
Sissoo Dalbergiasissoo fodder nectar and Terai, lower
pollen hills
Masala tree Eucalyptus nectar Terai, mid
camaldulensis hills
KaloSiris Albizialabbek nectar,pollen fodder tools Terai,midhil
ls
Gobresallo Abiespindrow Higher hills
Utish Alnus acuminate necter,pollen fodder nectar Mid and
higher hills
Neem Azadirachataindica Nectar,polle insecticides medicin Terai, lower
n es midhills
Khair Acacia catechu pollen
Fruit trees
Local name Botanical name Uses Suitable
area
 Amba Psidium fuel Pollen Terai, mid
guajava hills
Amp Mangifera fuel Timber Terai, mid
indica hills
Anar Punica fuel nectar, Terai, mid
granatum pollen hills
Sau Maluspumila fuel Nectar,polle Higher hills
n
Aru Prunuspersica fuel nectar, Mid and
pollen higher hills
Bhui- Ananussativus soil nectar, Terai and
katahar conservation pollen, soil midhills
conservation
Kagati Citrus fuel nectar, Terai and
aurantifolia pollen mid hills
Kera Musasapientum nectar, Terai and
pollen midhills
Lichi Litchi chinensis fuel nectar, Terai and
pollen lower hills
Mewa Carica papaya Terai and
midhills
Naspati Prunuscommunis fuel nectar, Midhillss
pollen
Nibuwa Citrus lemon fuel Pollen Terai, Midhills
midhills
Rukh- Artocarpus fuel Timber,fodd Terai and
katahar integrifolia er midhills
Amba Psidiumguajava fuel Fuel Nectar, Terai and
pollen midhills
Lapsi Chorcospondisauxill fuel Timber timber Mid and
aris higher ills
Rukh Artocarpus fuel Fodder nectar, Terai and
katahar heterophyllus pollen midhills
Bel Aeglemarmelos fuel Fodder nectar, Terai and
pollen lower hills
Katus Castanopsisindica fuel Fodder Midhills
Okhar Juglansregia Mid and
higher hills
Almond Prunusamygdalus fuel nectar, Mid and
pollen higher hills
Kaju Anacardium fuel pollen, Terai and
uccidenlale nectar lower hills
Nariwol Cocosnucifera fuel Brooms nectar, Terai
pollen
Lapsi Choreospondias fuel Timber Mid and
axillaris higher hills

Table 5.2: Major Agroforestry practices

S. Agroforestry Brief description (of Major groups of Agro ecological
No. practices arrangement of components(W-woody, adaptability
components) h-herbaceous, f-fodder
for grazing, a-animals)
AL SYSTEMS (Crops – Including shrub/vine/tree crops - and trees)
1. Improved Woody species planted w: fast-growing, In shifting cultivation
fallow and left to grow during preferably areas
fallow phase leguminous;
h: common
agricultural crops
2. Taungya Combined stand of w: usually plantation All ecological regions
woody and agricultural forestry spp.; (where taungya is
species during early h: common practiced); several
stages of establishment of agricultural crops improvements possible
plantations
3. Alley Woody species In w: fast-growing, Sub humid to humid
cropping hedges; agricultural leguminous; coppicing areas with high. human
(hedgerow, species in alleys in vigorously; population pressure and
intercropping) between hedges; h: common fragile (productive but
microzonal or strip agricultural crops easily degradable) soils
arrangement
4. Multilayer Multispecies multilayer, w: different woody Areas with fertile soils,
tree gardens dense plant associations components of varying good availability of
with no organisedplanting form and growth; labour and high human
arrangements h: usually absent; population pressure
shade - tolerant ones
sometimes present
5. Multipurpose Trees scattered w:multipurpose trees In all ecological regions
trees on haphazardly or according and other fruit trees; esp. in subsistence
croplands to some systematic h:common agricultural farming; also
patterns on bunds, crops commonly integrated
terraces or plot/field with animals
boundaries.
6. Plantation 1.Integrated multistory w: plantation crops In humid lowlands or
crop (mixed dense) mixtures such as coffee, cocoa, tropical humid/sub
combinations of plantation crops coconut etc. fruit trees humid highlands
2.Mixtures of plantation (esp. in 1); fuelwood / (depending on the
crops in alternate or fodder spp. (esp. in 3) plantation crops
other regular h: usually present in 4 concerned); usually in
arrangement. and to some extent in 1 small-holder
3. Shade trees for shade tolerant species. subsistence system
plantation crops; shade
trees scattered
4. Intercropping with
agricultural crops.

7. Home Intimate multistory w: fruit trees

in all ecological
gardens combination of various predominant also other regions; especially in
trees and crops around woody species, vines areas of high
homesteads etc. population density
8. Trees in soil Trees on bunds, terraces, w: multipurpose In sloping areas esp. in
conservation risers etc. with or and/or fruit trees. highlands, reclamation
and without grass strips; h: common of degraded acid alkali
reclamation trees for soil reclamation agricultural species. soils and sand dune
stabilization
9. Shelter-belts Trees around w: combination of tall- In wind prone areas.
and wind- farmlands/plots growing spreading
breaks, live types.
 hedges h: agricultural crops of
the locality
10. Fuel wood Inter planting firewood w: firewood species. In all ecological regions
production species on or around h: agricultural crops of
agricultural lands the locality
SILVOPASTORAL SYSTEMS (trees + pasture and/or animals
11. Trees on Trees scattered w: multipurpose of Extensive grazing
rangeland or irregularly or arranged fodder value areas.
pastures according to same f: present
systematic pattern. a: present
12. Protein banks Production of protein w: leguminous fodder Usually in areas with
rich tree fodder on trees high man: land ratio
farm/rangelands for cut h: present
and carry fodder f: present
production.
13. Plantation Example: cattle under w: plantation crops In areas with less
crops with coconuts in South- f: present pressure on plantation
pastures and eastern Asia and the a: present crop lands
animals South Pacific
14. Home Intimate, multistory w: fruit trees In all ecological regions
gardens combination of various predominate; also with high density of
involving trees and crops and other woody species human population.
animals animals around a: Present
homesteads
15. Multipurpose Woody hedges for w: fast growing and Humid to sub humid
woody browse, mulch, green coppicing fodder areas with hilly and
hedgerows manure, soil h: (similar to alley sloping terrain
conservation etc. cropping and soil
conservation)
OTHERS
16. Apiculture Trees for honey w: honey-producing Depending on
with trees production (other components feasibility of apiculture
may be present)
17. Aqua forestry Trees lining fish ponds, w: trees and shrubs Lowlands
tree leaves being used as preferred by fish (other
'forage' for fish components may be
present)
18. Multipurpose For various purposes w: multipurpose Various
wood lots (weed, fodder, soil species; special
protection, soil location-specific
reclamation etc. species (other
components may be
present)
 Past Questions
Agriculture and Forestry University faculty Agriculture
Office of the Controller of Exam Regular
Examinations Level Bachelor F.M. 20
Rampur, Chit wan. Program B. Sc. Ag. P. M 8
2074, Ashbin Year and Semester 4th Year, 7th Sem. Time 1:30 hrs.
Subject: HRT 406, 2(1+1) Agro Forestry
Candidates are required to give their answers in their own words as far as practicable. All questions
carry equal marks. Answer any 8 questions
1. Define agroforestry (ICRAF) and describe the consequences of forestation. (2.5)
2. Differentiate between boundary planting and wind breaks in an agroforestry systems. (2.5)
3. Write short note on protective benefits of an agroforestry systems. (2.5)
4. Agroforestry is a major key for sustainable agriculture, discuss. (2.5)
5. How agroforestry can be classified on the basis of space and time. (2.5)
6. Describe the benefits of improved fallow over bush fallow. (2.5)
7. Which agroforestry model will be suitable for Bara district of Nepal? (2.5)
8. List down the advantages and disadvantages of Taungya system of agroforestry system. (2.5)
9. Briefly mention the various factors and types of tree on crop interactions. (2.5)
------------------------------------------------------------------------------------------------------------------------

Agriculture and Forestry University faculty Agriculture

Office of the Controller of Exam Regular
Examinations Level Bachelor F.M. 20
Rampur, Chit wan.
Program B. Sc. Ag. P. M 8
2072, Push
Year and Semester 4th Year, 7th Sem. Time 1:30 hrs.
Subject: HRT 406, 2(1+1) Agro Forestry
Candidates are required to give their answers in their own words as far as practicable. All questions
carry equal marks. Answer any 8 questions
1. Describe the methods and tools used for D and D.
2. How does Agro-forestry help to reduce soil erosion and improve environment?
3. What is Neldes wheel model? Describe in brief.
4. Differentiate between contour hedgerow intercropping and alley cropping?
5. What is Taungya system of Agro-forestry? Describe its merits arid demerits.
6. Give an appropriate Agro-forestry system for Lamjung hills of Nepal. Support your answers with
diagram.
7. Classify the Agro-forestry on the basis of arrangement of components.
8. Describe the global need of Agro-forestry.
9. Define bole, boom, coppice, boundary planting and grove.
---------------------------------------------------------------------------------------------------------------------

Agriculture and Forestry University faculty Agriculture

Office of the Controller of Exam Regular
Examinations Level Bachelor F.M. 20
Rampur, Chit wan. Program B. Sc. Ag. P. M 8
2075, Karmic th th
Year and Semester 4 Year, 7 Sem. Time 1:30 hrs.

Subject: HRT 406, 2(1+1) Agro Forestry

Candidates are required to give their answers in their own words as far as practicable. All questions
carry equal marks. Answer any 8 questions
1. Define agroforestry and highlight the concentric design of agroforestry model. (0.5+2=2.5)
2. Calculate the volume of 12' (feet) long having 65" of girth management. (2.5)
3. Highlight the characteristics of trees which are used in agroforestry system. (2.5)
4. Enlist the ecological grouping of agroforestry system and also describe the appropriate agroforestry
system in upper hill of Nepal. (1+1.5=2.5)
5. Enlist the five tree species for wetland agroforestry system. (2.5)
6. Discuss the criteria of good agroforestry design. (2.5)
7. Briefly describe the advantages of tree/crop interface studies. (2.5)
8. Briefly describe the Nelder Wheel Model of agroforestry system. (2.5)
9. Write short notes on the following (any two): (1.25+1.25=2.5)
a. Contour hedge rod system of cropping model.
b. Pollarding
c. Gradient
-----------------------------------------------------------------------------------------------------------
Internal Assessment
2076
Subject: Agroforestry
Time: 30 minutes FM: 5 PM: 2
Attempt any 5 question
All questions carry equal marks.
1. Define agroforestry and highlight the need for agroforestry to sustain growing population.
2. Draw the model of contour hedge row intercropping and name 5 important MPTS.
3. List down how agroforestry helps to minimize soil erosion?
4. Differentiate between intermittent and interpolated.
5. Draw and label the Nelder Well Model.
6. Write the factors that affect the tree crop interface.
--------------------------------------------------------------------------------------------------

Agriculture and Forestry University faculty Agriculture

Office of the Controller of Exam Regular
Examinations Level Bachelor F.M. 20
Rampur, Chit wan. Program B. Sc. Ag. P. M 8
2076, Mangier Year and Semester th th
4 Year, 7 Sem. Time 1:30 hrs.
Subject: HRT 406, 2(1+1) Agro Forestry
Candidates are required to give their answers in their own words as far as practicable. All questions
carry equal marks. Answer any 8 questions
1. Discuss the characteristics of trees for agroforestry system with example. (2+0.5=2.5)
2. Briefly mention the importance and score of agroforestry in Nepal. (2.5)
3. Enlist five tannin producing agroforestry species (Botanical name) (0.5×5=2.5)
4. Calculate the volume of a log when the length is 12 feet long and girth is 5 inches. (2.5)
5. Discuss the hedge-row intercropping and concentric design of agroforestry model. (1.25+1.25=2.5)
6. Enlist the advantages of nursery rising of agroforestry species with example. (2+0.5=2.5)
7. Discuss the tree/crop interface studies with specific reasons. (2+0.5=2.5)
8. Discuss the key factors of D and D with example. (2.5)
9. Write short notes on (any two)
a. Gradients
b. Xylometric volume measurement
c. Agro-eco-zoning

 Good Luck 