SILVICULTURE

Paper - 1 | Section - A

EDITION : 2019
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 SYLLABUS

 GENERAL SILVICULTURAL PRINCIPLES : Ecological and physiological factors influencing

vegetation, natural and artificial regeneration of forests; methods of propagation, grafting
techniques; site factors; nursery and planting techniquesnursery beds, poly-bags and
maintenance, water budgeting, grading and hardening of seedlings; special approaches;
establishment and tending.

CONTENTS

SN Topic Page No
1. Forest, Forestry and silviculture 1 to 16
2. Site factors 17 to 19
3. Climatic factors 20 to 31
4. Edaphic factors 32 to 37
5. Physiographic factors 38 to 40
6. Biotic factors 41 to 43
7. Influence of forest over their environment 44 to 50
8. Form & growth of trees and crops 51 to 53
9. Crop morphology 54 to 65
10. Hardiness and tolerance 66 to 74
11. Forest succession 75 to 89
12. Forest types in india 90 to 97
13. Natural regeneration 98 to 113
14. Artificial regeneration 114 to 120
15. Choice of species 121 to 130
16. Seed supply 131 to 142
17. Forest nursery 143 to 160
18. Sowing and planting 161 to 172
19. Maintenance of plantation 173 to 177
20. Afforestation of difficult sites 178 to 193
21. Tending operation 194 to 216
 Topic 1 Forest, Forestry and silviculture

CONTENT :-
1. Forest : Definition & Classification
2. Forestry : Definition & Classification
3. Silviculture
4. Importance of Forest
5. Exercise

1.1 | FOREST

The term FOREST have their roots In medieval European, where there increasing
population as well as rise of new kingdoms and serfdoms based on heavy exploitation of natural
resources, caused heavy loss of Jungle (Natural vegetation) to feed their increasing demands of
food, fodder, fuel and Timber. Shrinking Jungles creates shortage of Fuel wood and Timber in
their ruling areas, so they start separating some part of land, which is usually unproductive and
located at the boundaries of village territory for rising tree crop that we known as FOREST or
WOOD LAND.

NOTE : FOREST term derived from a LATIN term FORIS which means OUTSIDE OF VILLAGE
BOUNDARY.
DEFINITION

 An AREA SET ASIDE for the production of TIMBER and other forest produce or to get
other INDIRECT BENEFITS from it.

 An UNCULTIVATED LAND occupied by NATURAL VEGETATIONS with closed or

partially CLOSED CANOPY, which provides shelter to the wild life.

 Any land area declared as Forest under any CENTRAL or STATE or LOCAL LAWS (i.e. by
Tribal council).

1.2 | FOREST CLASSIFICATION

FORESTS are classified into various categories for purposes of description,

administration, management and record; On the basis of -

A. Age basis
B. Regeneration basis
C. Composition
D. Ownership
E. Function
F. Legality
G. Growing stock
H. Ecological or Ecosystem based

A | AGE

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NOTE : Nature never produced Even aged forest, but man can by plantation i.e. Nilambur
teak plantation (1842). So in short, a true EVEN AGED FOREST MUST BE A MAN
MADE FOREST***.
NOTE : in case of Natural regenerated forest, for management point of view we could
consider them as even-aged forest by allowing upto 25 % of rotation age difference
in such case where forest is not harvested for 100 or more years***.

B | On the basis of REGENERATION

 HIGH FOREST : when regeneration obtain by SEED***.

 COPPICE FOREST : by COPPICE*** and other vegetative parts.

OR OTHER TYPE ?

 NATURAL FOREST : when regeneration obtain by natural means

 Man-MADE FOREST or PLANTATION : by Artificial means.

C | On the basis of COMPOSITION

D | On the basis of OWNERSHIP

 GOVT OWNED FOREST : 96 % forest area

 PRIVATE FOREST : own by industries i.e. BILT paper mill.
 PANCHAYAT or SOCIETY : Lalwan community reserve, Punjab.

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E | FUNCTION

 NATIONL FOREST POLICY (1952) : classified forest into 4 part on the basis of their
purpose of management i.e. Protection forest, National forest, Village forest and Tree
land.
 Similarly, NATIONAL COMMISSION ON AGRICULTURE (1976) : also classified forest

Forest Policy - 1952 NCA - 1976

1. PROTECTION Forests.
Protection Production Social
2. NATIONAL Forests. Forest Forest
3. VILLAGE Forests.
4. TREE-lands.

Valuable Mixed Inaccessible

Forest Quality Forest

F | LEGALITY or STATUTORY

An area declared as Forest under either Indian Forest act (IFA) 1927 or any other state /
local community law. Under Indian forest act 1927, forest could be classified as -

 RESERVED FOREST : have complete protection, Under “chapter II” of this act.
 VILLAGE FOREST : Aim to supply of forest produces to a village without disintegrating
their sustainability, under “Chapter III” of IFA.
 PROTECTED FOREST : Forest Area subject to limited degree of protection, exercises
control on felling and transport of timber, and removal of forest produce in whatever
form it may be. Declared under “Chapter IV” of IFA.
 UN-CLASSES FOREST : Forest lands owned by Govt.

NOTE : CONSERVATION RESERVE : Protected areas which typically act as buffer zones or migration
corridors between established national parks, wildlife sanctuaries and reserved forests.
Such areas are designated as CONSERVATION AREAS if they are uninhabited and completely
owned by the Government but used for subsistence by communities i.e. Ropar Wetland

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 conservation Reserve. If part of such area are privately owned then we called it
COMMUNITY RESERVE i.e. Lalwan community reserve, Punjab.

AIM : to extend the protection around the existing or proposed protected areas due to
private ownership of land, and land use.

WL (P) Act, 1972 : Amended in 2002, section 36A for declaring conservation reserve and 36C
for community reserve. (Remember Govt and Public always have 36 ka aankada).

G | GROWING STOCK

H | GEOGRAPHICAL or CLIMATIC / ECOLOGICAL BASIS

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 TROPICAL forest : Mt. SUBTROPICAL Forests :

Group 1 - Wet evergreen Group 8 - Broad leaved hill

(Tropical Wet evergreen Group 9 - PINE
forest) Group 10 - Dry evergreen
Group 2 - Semi-evergreen
Mt. TEMPERATE Forests :
Group 3 - Moist deciduous
Group 4 - LITTORAL AND SWAMP Group 11 - Wet
Group 5 - Dry deciduous Group 12 - Moist
Group 6 - THORN Group 13 - Dry
Group 7 - Dry evergreen

SUB-ALPINE forests : ALPINE Forests :

Group 14 - Sub alpine forests Group 15- Moist

Group 16- Dry

NOTE : We will study all of them more thoroughly in Topic Forest types in India.

----------------- EXERCISE – 1 -----------------------

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1.3 | FORESTRY

IFoS 2013 : Based on the objectives, what are the different classifications of the 'Forestry'?

1.4 | FORESTRY - CLASSIFICATION

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IFoS 2018 : Justify that the study of SILVICS is essential for the successful afforestation
programme in india (8m)

MODEL Q : define SILVICS and SILVICULTURE with their objectives and scope (10 m)

1.5 | SILVICULTURE

A | DEFINITION

 Silviculture is the ART and SCIENCE of cultivating forest crop → Annon. 1966

 The CARE and CULTIVATION of forest trees

 Silviculture is the THEORY and PRACTICES of raising forest crops → Champian & seth,
1968

 SILVICULTURE is the branch of forestry, which deals with the ESTABLISHMENT,

DEVELOPMENT, CARE and CULTIVATION of stand timber.

NOTE :-

 Analogy to agronomy
 Silviculture = SILVICS + its practical application
 Means – Practice of SILVICULTURE = Applied SILVICS

B | SILVICS

SILVICS is the study of LIFE HISTORY and GENERAL CHARACTERISTICS of forest tree
or crops with particular reference to environmental factors.

LIFE HISTORY : PHENOLOGY, Growth &

development.

GENERAL CHARACTERISTICS : Life form,

Tree morphology, Physiology and their
relationship with other trees or Crops

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Basically, SILVICS is the foundation of silviculture. It includes the study of Morphology,
Phenology, Physiology and reproduction - Growth & development of tree /Crops included
their relationship with other tree and crops.

C | OBJECTIVES

Our objectives of study SILVICULTURE are –

 Control CROP COMPOSITION – by controlling competition, diseases & Fire attack

 Production of LARGE VOLUME per unit area + ↑ QUALITY TIMBER
 Reduced ROTATION period
 AFFORESTATION & REFORESTATION, SITE PROTECTION.
 Introduction of EXOTICS i.e. Poplar, Eucalyptus
 Creation of MAN-MADE FOREST in place of Natural forest i.e. Nilambur teak

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D | Silviculture & other branches of Forestry

SILVICULTURE is the HUB (Backbone) of the forestry wheel. Other branches i.e. Forest
protection, F. Management, F. Mensuration, Economics, Soil etc. are supported by
Silviculture.

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IFoS 2018 : Justify that the study of SILVICS is essential for the successful afforestation
programme in india (8m)

Solution : SILVICS is the study of LIFE HISTORY and GENERAL CHARACTERISTICS of forest
tree with reference to LOCALITY factors, it helps in improving LIMITING factors
that regulate the growth and development of plantation/Afforestation.

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 FOREST FORESTRY SILVICULTURE ROLE OF FOREST HISTORY

IFoS 2012 : Discuss the ROLE OF FOREST in INTERCEPTION, surface runoff, Infiltration of rain
fall, regulation of stem flow and maintaining Soil fertility (5m)
IFoS 2009 : Describe the ROLE OF FOREST in Environmental Conservation (12 m)

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 FOREST FORESTRY SILVICULTURE ROLE OF FOREST HISTORY

 VEDIC PERIOD : In Vishnu Puran, there are 13 types of forest in different part of the country,
few of them are - ANGIREYA VANA (Bengal and Assam), Prachya vana (Bihar, UP, Nepal),
Naimisharanya (central UP), Panchanada vana (Punjab + J&K), Aparantaka vana (MH),
Dandkarandya van, Kalinga van, Kalesha van (south of river narmada), Vaman vana (near
Gwalior), Dasarnaka vana (around Bhopal, sagar, damoh) and Karush van (Baghel & bundle
khand).

They also divided forest into – Kunjar van (dense/elephant forest) and kantak van (thorny scrub
forest).

 MAURYA PERIOD : kautilya arthashastra – head of forest dept “Kupyadhyaksha”

assisted by a number of vanpalss (Forest guards). They classified forest into 4 parts (1)
forest reserve for king, (2) reserve forest for state, (3) forest donated to the Brahmins
and (4) forest for public.
 Gupta period : destruction of forest in central india
 Mughal :
 British period :
1790  Tipu sultan introduces Eucalyptus in Nandi hills, Mysore.

1806  Captain Watson appointed as first Conservator of forest by Govt. of Madras

1828  Wasteland declared as government properties

1842  Conolly, Collector of Malabar region establish Nilambur Teak plantation +

Afforestation work started

1843  Champell introduces Eucalyptus pinnata at Wellington, Madras

1854  First Zoo in India (Calcutta Zoo, West Bengal)

1856  Cleghorn is appointed as first regular Conservator of forest

1864  Forest department set up + Scientific forest management started in India

 Dietrich Brandis appointed as first IGF of India

1865  Indian Forest Act passed

1866  Changamanga fuel wood plantation established

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 1867  Indian Forest Service started

1875  1st copy of Indian forester journal issued by Baden Powell and Dr. Schlich

1878  Forest school at Dehradun started.

1879  Elephant Preservation Act passed

1883  BNHS (Bombay Natural History Society) started

1884  Forest school renamed as Imperial Forest School

1885  Training for forest officers of India started at Cooper's Hill, England

1890  Dr. Voelkar from Germany starts study on Indian agricultural problems

1894  First Indian Forest policy passed

1898  Vedanthangal declared as a first wildlife sanctuary in India

1905  World Forestry Congress set up

1906  Imperial Forest School renamed as Imperial Forest Research Institute now
it is known as Forest Research Institute (FRI), Dehradun

1927  Indian forest act

1936  1st national park “Hailey”

 AFTER INDEPENDENCE :

1948  Central board of Forestry

1949  M.D. Chaturvedi — First Indian Inspector General of Forest

1950  Van mahotsav

1952  National forest policy with target of bringing 1/3 of GA under forest
cover
 Indian Board of Wildlife

1957  Hailey National Park renamed as Corbett National Park

1959  Logging Research Institute at Batote established

1960  Prevention of Cruelty to Animals Act passed

1961  Forest seed testing started in FRI, Dehradun

1965  Pre-Investment Survey of Forest Resources (PISFR) published the

Forest Type Map of India.

1966  Seed act

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 1968  Champion and Seth classify the forests of India into 16 forest types
 Westoby coined the word "SOCIAL FORESTRY" in world forestry
congress held in India

1970  Gujarat became the first Indian state to start Social forestry
programme
 Project "Hangul" started in J&K

1972  Project Lion started at Gir sanctuary.

 WL (P) Act

1973  Project tiger + Chipko movement

 UNESCO starts MAB (Men and Biosphere) program

1975  Crocodile Breeding and Management project launched

 Forest and Wildlife brought on concurrent list in the 7th schedule by
42"d Amendment to the Constitution

1976  NCA report published

1979  Social Forestry project started

1982  IIFM + FSI + WII

1983  First National Wildlife Action plan adopted

1984  MOEF (Ministry of Environment and Forest) created

1986  First biosphere reserve in India — Nilgiri Biosphere Reserve.

1987  ICFRE (Indian Council of Forest Research & Education) established at

Dehradun

1988  2nd National forest policy

1992  Project Elephant started

2002  Biological Diversity Act passed

2006  National Bamboo Mission

 FRA (Forest Right Act) passed

2010  National Green Tribunal Act (NGT)

2014  3rd meeting held on World Congress in Agroforestry, New Delhi

2018  Draft national forest policy released for public opinion

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 Chapter 2 SITE FACTORS

CONTENT :-
6. Site ? & Site factors
7. Site quality and its classification
8. Exercise

2.1 | SITE

 SITE or LOCATION - is an area or a place on which you cant to carried out plantation
work

 SITE or LOCALITY or HABITAT FACTORS : are the sum of all effective conditions of a
particular area under which a plant community lives.

Or
All physical and biological factors of an area which determined the occurance,
distribution and growth of vegetation.

These factors are –

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 1. CLIMATIC : Solar radiation, Humidity, wind, Air temperature
2. EDAPHIC : Soil organic matter, soil texture, structure
3. TOPOGRAPHIC or physiographic and
4. BIOTIC.

2.2 | SITE QUALITY

 SITE QUALITY : The relative productive capacity of a site for a particular species or
group of species.
Site quality is a measure of the ability of a piece of land to provide the
resources needed for plant growth i.e., how nutrient rich is the soil, how well does the
soil hold water, how deep is the soil, how much sunlight reaches the area.

 SITE QUALITY DETERMINATION : by SITE INDEX.

NOTE : SITE INDEX

₋ Direct measure of site productivity
₋ Defined = average height of dominant and codominant trees that have been
free-to-grow (not suppressed) in a stand at some base index age (usually 50
years for hardwoods and 25 years for softwood) for a particular species.
₋ Indirect measures of site productivity: soils, landform, indicator species
₋ Site index curves allow estimation of site index before and after the base age.

 SITE QUALITY CLASSIFICATION :

We can classified site as - Poor, Good, very good or excellent, on the basis of –
A) VEGETATION IN THE FIELD : by the help of ① indicator spp (Barren land, Grass,
Tree etc.), ② Total volume produced by the crop, ③ growth rate of a sp p i.e.
MAI/CAI etc.
B) By the help of SOIL, TOPOGRAPHIC AND CLIMATIC CONDITIONS

NOTE : MAI & Tree height are the best indicators of site quality

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2014 : Why does height of a tree considered a better criteria for a site selection than its
diameter discuss (5m).

2.3 | EXERCISE

 2014 : How is site quality important in timber production ? discuss the methods used to
measure the site quality (15 m).
 2011 : Why are locality factors considered importance for any silvicultural operation ?
 2010 : What do you understand by the term Locality factors ? how these affect the decision of
plantations undertaking by the silviculturist ? (10 m).

Linked Questions :

 2018 : explain the Eco-physiological factors that are more concerned to silvilulturist (15 m).
 2014 : why does height of a tree considered a better criteria for a site selection than its diameter
discuss (5m).

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EXERCISE

 2018 : Can ‘climate change’ changed the period of phenology ? share with examples (10 m).
 2017 : Regulation of solar radiation given a powerful tools to the forester justify (10 m).
 2015 : How can a forest with shade bearer and light demander tree species be managed under
uniform shelterwood system ? (10 m)
 2014 : Explain the importance of snow in regeneration of cedrus deodara (5).
 2012 : How snow affects the forest vegetation ? (5m)

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 Topic 4 EDAPHIC FACTOR

CONTENT :-
1. Conceptual Part
2. Mycorriza
3. Biofertilizers & Rhizobium
4. Micronutrients
5. NOTE : Soil types in india
6. Exercise

4.1 | CONCEPTUAL PART

 SOIL : the uppermost weathered layer of earth crust

 FOREST SOIL : A porther of eath surface which served as a medium for the growth and
sustinace of forest vegetation.
 SOIL TYPES IN INDIA :
 SOIL DISTRIBUTION :

4.2 | MYCORRHIZA

DEFINITION :

 Mycorrhiza is the symbiotic relationship b/w fungi and higher plants

(Remember : Myco = Fungi (Mycology) + Rhiza = Rhizome = Roots)

TYPES :

 ECTO-MYCORRHIZA : in this fungal hyphae formed a cover over the lateral roots called
MANTEL as wel as its hyphae penetrated into the inter-cellular space of root cortex and
formed a net like structure called HERTING NET, however they didn’t established a
direct cytoplasmic contact with cortex cells.
₋ Fungi group : Ascomycetes & basidiomycetes
₋ Plants : most common in conifers i.e. Chir Pine, deodar

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 Endo-Mycorrhiza : unser this, Fungal hyphai entered into the cell and established direct
contact with the cytoplasm of cortex cell. As they established direct contact so there is
no needs of formation of Herting net or fungal Mantle.
₋ Most common types of mycorrhiza and formed in almost 90 % herbaceous and
woody plants
₋ Fungi : Phycomycetes or VAM (vascular arvascular mycorrhiza).

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  Ecto-endo-mycorhiza :

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IMPORTANCE OF MYCORRHIZA :

 Absorbtion of soil moisture : increases by increasing water absorption surface area

 Inrease minirals availability to the plant : by absorb some minirals themselves or by
make them in absorbable form through releasing enzymes i.e. Phosphorus
 Nitrogen Fixation : increase nitrogen availability to the plant
 Produce some growth hormones i.e. Auxin, gibbralin that further boost-up plants root
growth.

INOCULATION OF MYCORRHIZA INTO THE PLANTATION SITE OR NURSERY PLANTS ROOTS :

 By planting infected plants & roots in a site/nursery bed.

 By inoculating Fungal Spores and Mycelium

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4.3 | BIO-FERTILIZERS

Biofertilizers are the artificially developed culture of usefull microorganisms of soil

and plant origin, which are used as inoculants od seed, root of seedling and soil in the
nursery.

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4.4 | SOIL NUTRIENTS

We will study all of them in one place : Soil science

4.4 | EXERCISE

 2018 : Write in detail about the influence of parent rock in the distribution of tree species.
 2017 : Discuss in detail, the kind of mycorrhiza and the benefits derived by plant from them (8m)
 2016 : white the importance of soil organic matter in forest. How is calculation of seedlings
carried under Line, square . . . .... (20 m)
 2014 : Difference b/w Ectomycorrhizae and endomycorrhizae
 2013 : write a note on ‘role of microorganism and rhizobium in amelioration of forest soils (10 ).
 2013 : What are the source and nature of elements considered as essential plant nutrients (10
m).
 2012 : Difference b/w Ectomycorrhizae and endomycorrhizae
 2011 : Difference b/w Ectomycorrhizae and endomycorrhizae with respect of structure and
function (10 m).
 2010 : How are ectomycorrhizal fungi beneficial in managing soil born diseases of forest
nurseries ? gives examples (10 m).

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 Topic 5 PHYSIOGRAPHIC FACTOR

CONTENT :-
7. Factors ?
8. Exercise

5.1 | INTRODUCTION

 It influenced vegetation indirectly by influencing local climate

 Factors are –
₋ Configuration or arrangement of land surface i.e. hills & velleys
₋ Altitude
₋ Latitude
₋ Slopes
₋ Aspect & Exposure
₋ Surface condition

 ARRANGEMENT OF LAND SURFACE : arrangement of hills and valleys affect local

climate by affecting rainfall pattern, wind direction, temperature and solar radiation.
With this it also affect wind direction which is important for pollination and seed
dispersal in conifers.

 ALTITUDE : heght of a place from mean sea level, with increasing altitude usually
rainfall, temperature, pressure & soil fertility decreases, and wind velocity, solar
radiation increases.

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 Example : inner Himalaya received very low precipitation (below 60 cm).

EFFECTO FO ALTITUDE ON VEGETATION :

₋ It reduce plants height & diameter and formation of flag tree

₋ Reduce Form factor, thickness and size of Leaves
₋ Induced root growth
₋ High transpiration due to high solar radiation intensity results may plants
competeout from this location.
 SLOPES : the angle b/w the land surface and the horizontal plane. It responsible for soil
erosion and changing soil properties, soil material movement (i.e. Land slide,
Solifluction).

 ASPECT & EXPOSURE :

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 ASPECT Northern face of our Himalaya has dencevegetation

Why is our Himalayas Northern face have dence forest vegetation whereas Southern face
are virtually barren ?

 Southern slopes get more horizontal radiation = more heated up = more evaporation
of water = less water available for vegetation = poor vegetation growth (despire of it
gain more rainfall during monsoon period).
 Norther phase : less radiation = low temperature = more humid condition = more
vegetation

5.2 | EXERCISE

 2015 : Latitude influences the forest types of the earth explain (10 m).
 2013 : Configuration of the land surface has an impact on local climatic conditions and wind
movement, which in tum have a bearing on forest." Comment (8 m).

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 Topic 6 BIOTIC FACTOR

BIOTIC FACTORS are the biotic agencies which influence the growth and development of
vegetation either individual crop or over crops.

 Climatic / Edaphic / Physiographic factors affects whole crop, where as Biotic factors
may affect individually (Sal heartwood borer) or collectively.

RELATIONSHIP IN BIOTIC FACTORS

 Relationship b/w Plants : where 1 plant species affects the growth, development and
distribution of other plant species through the mechanism of -

 COMPETITION : for light, moisture, space and Nutrition. So only healthy and vigour
growth plant can survive.
 SYMBIOTIC relationship : helps both species to survive under stress conditions i.e.
Mycorrhiza, rhizobium in lagumes.
 PARASITIC : when one species depent for food and protection over other plant
species and sometime they remove the later from its natural habitat i.e. Cuscuta
(Amarbel or madar) a total stem parasite.
 EPIPHYTES : grow over other plant (have no soil contact) i.e. Orchids

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  CLIMBER : tendril plants clim over the other plant, but they have their roots in the
soil i.e. Lianas, Bauhinia etc.

 Relationship b/w Plants and Animals : where survibability of a specific plant species
may controlled or regulated by Animal species through mechanism of -

 Seed and pollen dispersion -> helps in its distribution

 Insects /pests -> cause diseases
 Wild animals distoyed seedlings i.e. Porcupine destroyed bamboo seedling

 Relationship b/w Plants and MAN : here man is the majour factor for the extinction of a
usefull plant species in its natural habitat.

 Shifting cultivation
 Forest fire
 illicit felling and encroachment
 Grazing and lopping
 Deforestation

EXERCISE

 2018 : Explain the ecophysiological factors that are more conceren to silviculturists (15 m)

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Linked Questions

 2018 : write the problem and prospects of exotic tree species in india with suitable examples (15)

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 Topic 7 INFLUENCE OF FOREST ON THEIR ENVIRONMENT

CONTENT :-
9. Introduction
10. Effects of forest on their climate
11. Effects of forest on soil
12. Effects of forest on water cycle
13. Forest and soil erosion
14. Wildlife + global warming, pollution, GHGs (Not included in this edition)
15. Exercise

7.1 | INTRODUCTION

A Natural forest influenced their local environment through the activity of –

(a) The unbroken canopy in a fully stocked forest intersept sun’s rays and precipitation,
retard wind velocity and loss of heat radiation through long wave radiation resultant
creation of their own micro climate.
(b) Trees ability to recycled minerals, reducing bulk density and falling down of Large
quantity of leaf litters protect and changed the soil property.
(c) Interlocking root system bind the soil -> reduce its erodibility.
(d) As it change its environment, subsequently new environmental factors further induced
changes in the vegetation till both achieve its maximum (Climax community), during
this process it also remove many plants and animal species composition.

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EFFECTS OF FOREST ON THEIR ENVIRONENTAL FACTORS ?

A) Local climate
B) Forest hydrological cycle
C) Forest soil (Edaphic) +
D) Soil erosion and flood
E) Wildlife
F) Global warming, Pollution, GHGs etc.

7.2 | EFFECTS OF FOREST ON THEIR CLIMATE

 WIND VELOCITY : forest creates mechanical obstruction and major part of it deflected
upwards, and slowing down the part of wind which entered into it. A average dence
forest reduce ≈ 20 to 60 % of wind velocity than the open.

We often used this capability of trees to protect our farms and building from very cold
& warm winds by creating SHELTERBELT and WINDBREAK (Further detail in Agroforestry).

 HUMIDITY : Tree absorbed large amount of water from the soil. Only avery small part (1
to 2 %) of this water they utilized in its metalolic activities and the remaining 98/99 %
lost through transpiration (vapour form) resulting 5 to 15 % more humidity than the
open i.e. Eucalyptus evaporate ≈ 3500 Tonnes ot water per hectare per annuam.
 LOCAL TEMPERATURE : Forest reduce local air temperature by pouring out huge
amount of water into the air through transpiration (Physiologycal process), resultant it
decrease temperature ≈ 2 to 3o C .
 LOCAL PRECIPITATION : Huge amount of water pouringout by the forest trees into the
air increase its saturation + Forest role in reduction in temperature = Air become
oversaturated and often create local rainfall when local wind move them toward the
local mountains. So forest increases ≈ 15 to 20 % more rainfall than the open land.
 FROST : No or very negligible effect on the ground vegetation as closed canopy creating
insulating effect through preventing entering cold air into the forest + very little
temperature change + prevent moving out of long wave radiation. Forest also delayed
melting of SNOW in temperate forest.

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 In GLOBAL WARMING : global warming is the result of absorption and emitting back of
long wave radiation by the GHGs. Despite of Forest as having one of the source of GHGs
emission through forest fire and decaying of Organic matter, its positive role play far
beyond it though – Sink of GHGc & CO2 and its capability of long term carbon store into
the soil.

Total 6622 MMT of carbon is stored in Indian (forest + TOF), and they neutralized ≈ 12
% of GHGs of india (ISFR 2009)

7.3 | EFFECTS OF FOREST ON SOIL

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7.4 | EFFECTS OF FOREST ON WATER CYCLE

Forest affects hydrological cycle considerably through the mechanism of interception, stem
flow, Percolation and infiltration. Because of this major chunk of rainfall retain in the local
area (use term FOREST STAND during
writting in your exam).

 INTERCEPTION : is the part of

precipitation whch is cought by
vegetation cover, However rte of
interception inversly proportion
to the rainfall intensity.
RATE : 15 to 30 % of total
precipitation
 STEM FLOW : Downward
movement of water by using tree
stem surface
 INFILTRATION : Entry of water
into the soil (5 % higher than
open field)
 PERCOLATION : downward
movement of water through soil
profile
 RUN-OFF : reduce surface runoff

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7.5 | FOREST and SOIL EROSION

Forest increase interception = less water available for runoff = Controll erosion and flood in
lower reaches.
Examples : Dense forest in himalayas reduce flooding issue in North Indian plain

HILLS BEFORE DEFORESTATION AFTER DEFORESTATION

NOTE : Wildlife + Global warming, Pollution, GHGs etc these are easy topic so prepair them by self or we
discuss them at the end of syllabus to save unnecessary time wastage.

7.1 | EXERCISE

 2016 : Justify the statement “ Forest substantially check soil erosion and control runoff (8m).
 2016 : Comment “Forest has moderating influences on soil and air temperature (8 m)
 2016 : Explain the role of forest in environmental conservation (10 m).
 2012 : Comment critically “Recycling of nutrients in Natural forest” (5 m).
 2012 : Do forests influence the rainfall ? If so, how ?
 2011 : Compare Nutrien cycling in a forest, an agroforestry system and in an agriculture field.
Discuss how it helps to sustain soil fertility (10 m).
 2007 : Discuss the impact of forest on the climate of a locality, how do forest affects soil and
water conservation (20 m).
 2007 : Discuss the impact of deforestation on ecological aspects (20 m).

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 Topic 8 Form and Growth of trees

I did not find any question from this topic directly but this topic actually making the base of
other questions as well as makes them easy to understand.

8.1 | BASIC TERMINOLOGY

 HERB : Plants whose stem is always green and tender and height is usually not more
than 1 meter. They may be Annual, Biennial or perennial.
 SHRUB : a woody perennial plant differing from a perennial herb in its persistence and
woody stem and its habitat of branching from the base.
 TREES : A large woody perennial plant having a single well defined stem (Bole/Trunk) and
more or less defined crown.

Herb Shrub Tree

 SPECIES : group of individuals of plants having close relation structurally and functionally
as well as they can interbreed and generate fertile offspring (i.e. Human)
 RACE : Group of individuals having some specific characters (i.e. Chinese race in Human
species)
 STEM : a perennial axis of plant on which buds and shoots are developed
STEM = BOLE = TRUNK (synonyms)
 FORKING : when stem has more than 1 leader, common in broad leave species.
 LIGNOTUBER : a Lignotuber is a starchy swelling of the root crown or stem base in some
plant species. Aim : protection against distruction of main stem against fire and other
factors. i.e. in Eucalyptus.

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 BUTTRESSING : Buttresses are the outgrowth at the base of the stem, usually vertically
and connected the base of the stem with roots mote strongly.

LIGNOTUBER Buttressing Root nodules

 ROOT NODULES : Root nodules are organs induced in most species of legume plants by
symbiotic, N-fixing bacteria i.e. Rhizobium, Azorhizobium.
 PHENOLOGY : Seasonal changes in the plant i.e. flowering, fruiting, leaves shedding etc.

8.2 | GROWTH

 Growth is the permanent and irresistible increment in size

 STAGES OF TREE GROWTH :-

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 (a) Recruit : From germination to the stage that the young trees has a few leaves.
(b) Seedling : From recruit stage upto a height of 1 m of the young plant.
(c) Sapling : From the time the young tree reaches 1 m height till the lower branches
begin to fall.
(d) POLE : From the fall of the lower branches to the time when the rate of increase in
height begins to fall and the crown expansion becomes marked.
(e) TREE : After passing the pole stage.
 TREE HEIGHT GROWTH : by Apical meristem

Factors that affects the tree height growth :

1) Genetic makeup of tree

2) Site quality : height of plant on best site is usually 1.5 to 4 time higher than poor
site.
3) Density and composition of vegetation.

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 Topic 9 CROP MORPHOLOGY

Content :
1. Introduction
2. Differentiation on the basis of age
3. Differentiation on the basis of composition
4. Differentiation on the basis of density
5. Crown classification
6. Exercise

9.1 | INTRODUCTION

 Study of outer form of the forest crop consisting of trees and its development is called
CROP MORPHOLOGY.
 FOREST : A plant association predominantly of trees or other woody vegetation or a
collection of stands.
 STAND : An aggregation of trees or other growth occupying a specific area and
sufficiently uniform in species composition, size, age, arrangement, and condition as to
be distinguished from the forest or other growth on adjoining areas.

Stand is the part of forest, so for studying crop morphology we usually used
stand as a medium of study. Stand are differentiated on the basis of – Age, Density,
Composition, tree Crown and many other factors. (Here we study only 1 st four remaining
factors we study in Forest management chapter 10 : Stand structure & dynamics).

NOTE :
₋ A forest is a COLLECTION OF STANDS
₋ Remember that the stand is the unit which is of silvicultural interest. The
forester practices silviculture on stands not on forests. It is not an ecological
management unit.
₋ Importace of stand : Stand level modelling

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9.2 | DIFFERENTIATION ON THE BASIS OF AGE

 EVEN AGED CROP :

In even-aged stand, almost all trees having the same age or at least of the same
age Class. If variation in age among the individuals of the stand is more than 25 per cent
of the length of rotation

ADVANTAGES OF EVEN-AGED STANDS :

1) There is greater uniformity in size and shape of the trees

as all tree having same age and space for growth with
similar condition.
2) Better bole formation, trees grow too larger heights,
have longer clean bole
3) better natural pruning owing to intense competition in
the crop,
4) Development of smaller crowns,
5) Better quality of wood, less taper and
6) Easier and cheaper to apply silvicultural operations e.g.
thinning, pruning, felling etc.

Sometimes, it is observed that the above advantages are either not visible in the
crop or not fully realised due to several factors. From even-aged stands, mostly economic
advantages accrue.

DIS-ADVANTAGES OF EVEN-AGED STANDS :

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Even aged stands have certain disadvantages or In other words un-even-aged stands have
certain merits which are not available in even-aged stand. These are :

1) The soil is better utilized and more uniformly protected in the uneven-aged stands as
tree of different strata have their roots at different level of depth as well as canopy is
deeper and thick protected from external forces.
2) In even-aged stands, there is no or very little advance growth but in uneven-aged
stands, natural regeneration of several species is easily attained.
3) The even-aged stand is more adversely affected by wind, snow, insect attacks.

 UNEVEN AGED CROP :

An un-even-aged stand Contains at least three age classes. on the basis of

distribution of stems of different age classes uneven-aged stand can be classified as

(a) balanced uneven- aged : each age class occupies almost equal area.
(b) irregular uneven-aged stands : it does not contain trees of all ages or age classes,
so it do not ensure regular yield on sustained basis.

9.3 | DIFFERENTIATION OF THE BASIS OF COMPOSITION

A stand may consist of a single species or several species. When the stand is formed
by single species it is called PURE STAND and that consisting of several species is called
MIXED STAND.

For management purpose, if a species constitutes more than 50 per cent or more in
the over-wood, it is usually classed pure stand.

PURE STAND

 ADVANTAGES :
Although pure stands are ecologically less desirable than mixed stands, there are several
advantages in the management of pure stands. These advantages are :

1) Management is simple because all trees are almost same size, age and height.

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 2) Application of various silvicultural operations i.e. thinnings, fellings etc. require less
skill and time.
3) We get more uniform Natural pruning in pure crop than in mixed stands.
4) Produced timber of higher quality with less taper.
5) We can grow species which have market demand
6) Economical : Raising of plantations of a single species is easier and less expensive.
Later when we got mature crop, its Same size and uniform spacing make easy to
mechanised harvesting = cheap harvesting = more economical.
7) The resulting crop is more uniform in quality of wood, shape and size.
8) There are no unnecessary sacrifices of the increment of valuable species in
intermediate felling.

 DISADVANTAGES :

The advantages of mixed stands form the disadvantages of pure stands. The advantages
of mixed stands or we can say disadvantages of pure stand are as follows –

1) Mixed stand utilized the site more efficiently and completely as they have different
level of root depth, root pattern and horizontal-vertical crown differentiation
(means it is not fully utilized in pure stand).
2) Pure forests (e.g. Teak plantation) are create adverse effect on site. There is a
greater risk of soil exhaustion and deterioration under pure crops but not in mixed.
3) Mixed stands are better protected from epidemics of insect-pest and diseases .
4) A mixture of shallow rooted species with deep-rooted species protects the stands
from wind damage. Similarly, frost and snow tender species can be grown with
hardy species.
5) The fire danger is much greater in case of a single species particularly in conifers.
The severity of fire depends upon the nature and amount of dry leaf litter. Species
in mixed stand may have different period of leaf shedding and quicker
decomposition resulting in lesser amount of available litter. Coniferous needles,
being resinous in nature produce quicker and hotter fire than most hardwood
species. Crown fires which are most destructive are mostly confined to pure forests
of coniferous species

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 6) Mixed species are better adapted to poorer sites, better maintain soil properties
because they draw varying quantity of nutrients and water from different depths of
soil as against pure crops which make on same depth.
7) Mistakes made in selection of species in artificial regeneration are more easily
corrected in mixéd crops than in pure crops. When one or more species planted in
mixed stands are found unsuitable, they can be removed during cleaning and
thinning and only such species are maintained for final crop which are best suitable
to the site. In pure stands, there is no possibility of such manipulation.
8) Natural regeneration of mixed forest is easier + less dangers for seedlings to be
affected by frost, insect pests and diseases.
9) Mixed stands are more desirable from an aesthetic point of view than pure stands.
If forests are to be protected and maintained primarily for aesthetic value, mixed
stands would be recommended.
10) Mixed stand is more easily converted or modified to meet the present and the
future demands of the market.

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MIXED STAND

A stand may consist of several species is called MIXED STAND. Its 2 types

(i) Artificial or man-made mixed stands

(ii) Natural mixed stands

 NATURAL MIXED STANDS : in natural condition trees never grow in specific

arrangement they usually randomly scattered in

o GREGARIOUS - when species occur naturally almost in pure stands,

o CONSORTING - when a species grown is mixtures but forms a considerable part of
the crop and
o CONCOMITANT, when a species grows in mixtures but forms only a part of the
crop.

 ARTIFICIAL MIXED STANDS : When a forest is created artificially, it is easy to raise a

single species for the entire area. Considering the advantages of a mixed stands,
foresters have also started raising mixed stands. The most common forms of mixture
are –
1) Sporadic mixtures : obtained by sowing of mixture seeds or by planting alternately
plants of of different species.

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 2) Line mixtures : obtained by raising different species in different lines or strips
alternately.
3) Group or block mixtures : obtained where group of trees of different species
Planted in blocks.

9.4 | DIFFERENTIATION OF THE BASIS OF DENSITY

 DENSITY is the relative closeness of trees in a stand

↳ with respect of crown = CROWN DENSITY.
↳ with respect of Stem = STEM DENSITY or CROP DENSITY.

 The efforts of foresters are always aimed to achieve crop having closed crown
throughout the life of the stand. This is because the production of goods and services is
directly linked with the crop or crown density.

NOTE :
 Density refers to relative closeness of trees in a stand. The closeness may be with respect to
crown, called CROWN DENSITY and/or with respect to stem, called CROP DENSITY.
 The relative completeness of the tree stocking expressed as a decimal coefficient, is called
CROP DENSITY.

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DENSITY CLASSIFICATION :

CANOPY CLASS DENSITY

OPEN When the density is under0.5

THIN density is between 0.5 and 0.75

DENSE When the density is between0.75 and 1.0

CLOSED When the density is 1.0

 FACTORS AFFECTING DENSITY : 4F+

 Species composition
 Mode of regeneration
 Soil fertility
 Moisture availability
 Biotic interference

9.5 | CROWN CLASSIFICATION

In order to decide several silvicultural operations e.g. thinning, fellings etc. Trees are
usually classified on the basis of position of the crown in the crop. Several factor i.e. age,
species, Competition size, height, etc. decide the development of crown in a crop.

 CROWN CLASSIFICATION FOR EVEN AGED CROP STAND OR REGULAR FOREST : On next
page.
 CROWN CLASSIFICATION FORUN-EVEN AGED STANDS : When trees of different species
of all ages are present in a mixed stand, certain species may stand under the crown of
others and still not be suppressed so far as their growth is concerned. Several systems of
classification are suggested but none of them have been widely adopted. The crown
classification in irregular stands suggested by Seth (1956) based on replace the different
crown position by degrees of crown freedom, these being further classified according to
crown size.

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9.6 | EXERCISE

 2014 : Describe the characteristics and structure of an EVEN-AGED STAND (10 m).
 2014 : What is STAND DENSITY ? How spacing is used to control stand density ? Discuss (15 ).
 2014 : Mixed forest stand offer complete utilization of land. Comment (8 m)
 2012 : Canopy architecture in forestry
 2010 : Pure stand of forest result incomplete utilization of site comments on the following
(5m).

Linked Questions :

 2017 : Why SITE SPECIFIC PLANNING is essential for forest management ? Explain different
components of site-specific management (8m).
 2014 : How is SITE QUALITY important in timber production ? Describe the methods used to
measure the site quality (15 m).

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 Topic 10 HARDINESS AND TOLERANCE

In normal condition of soil, air and water provide suitable environment condition for the
growth of most of the plants. However there are large areas where normal condition of climate
and soil do not exist and only such plants are able to grow which are either able to adapt these
local condition or develop resistance to these condition
Hardiness : the ability of plant's to survive under adverse growing conditions like cold, heat,
drought, flooding or wind is called hardiness.
Tolerance :

HARDINESS AND TOLERANCE OF PLANTS AGAINST :

1. Drought condition
2. Water logging condition
3. High salt concentration
4. Low temperature & frost
5. High temperature

10.1 | DROUGHT CONDITION

 The shortage of moisture due to low rain fall,

 The plants they grow in very dry habitat are known as XEROPHYTES

TYPES OF DROUGHT :

1. METEOROLOGICAL DROUGHT: This happens when the actual rainfall in an area is

significantly less than the climatological mean of that area.
2. HYDROLOGICAL DROUGHT: A marked depletion of surface water causing very low
stream flow and drying of lakes, rivers and reservoirs
3. AGRICULTURAL DROUGHT: Inadequate soil moisture resulting in acute crop stress and
fall in agricultural productivity, it is the impact of meteorological/hydrological drought
on crop yield.

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 PLANTS ADAPTATIONS FOR DROUGHT CONDITION
WATER TAPPERS
WATER SAVER WATER STORERS
OR
PHREATOPHYTES

A | Water tappers or PHREATOPHYTES

 Some Plants develop remarkably long tap root (Deep-root) system

and they able to tap deep ground water.
 These such plants grow on sand dunes and desertic condition
Examples : Prosopis juliflora, P. cineraria,
Acacia nilotica, A. Senegal,
Azadirecta indica, Zizyphus mauritiana,

B | WATER SAVER

 Mainly in CAM plants (Crussulaceae family)

 They save water by the following adaptation:

(a) Ability to close the stomata rapidly & completely

(b) Sunken stomata
(c) Thick and highly water proof cuticles
(d) High osmotic pressure
(e) Mechanism that reduse transpiration

(a) ABILITY TO CLOSE THE STOMATA RAPIDLY & COMPLETELY : Before the cells damaged by
desiccation, several species are able to close their stomata.
(b) SUNKEN STOMATA : In xerophytes, stomata, rather than being found on the leaf surface,
are found embedded deep into the leaf layers and are partially covered by cuticle and hair
(trichomes). This feature helps in controlling the excessive water loss due to transpiration in
these plants.

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(c) THICK AND HIGHLY WATER PROOF CUTICLES : The leaves of xerophytes, often covered by
thick waxy layer (cuticle). These layers resist to vapour loss is 4-5 time higher then non-
xerophytic plants.

(d) MECHANISM THAT REDUCE TRANSPIRATION : In C3 & C4 plants generally stomata open
during the day time and allow the CO2 entry for photosynthesis, but this strategy induced
greater loss in transpiration, when air is hot and dry. So the desert vegetation (CAM plants)
open their stomata in night and close during day time, hence reduce water loss. Another
mechanism is to rolling-out and rolling-in of leaf to reduce effective leaf surface area.

C | WATER STORERS

 Their roots become flashy and thick due to storage of water i.e. Cacti & Euphorbia
 They are the true Xerophytes

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10.2 | LOW TEMPERATURE AND FROST

All physiological activities in plants take place within an optimum range of temperature.
When temperature decreases above this range, all physiological activities are adversely affected
and when temperature decrease further plants may die. Ability to resist and adopt low
temperature is very with plants to plants.

MECHANISM TO RESIST LOW TEMPERATURE :

Resistance
SN Character Causes of resistance
Low High

Greater amount of cell

Water content
1 of cell wall water caused danger
of cell water freezing

More water → low resist. Low water → high resist

Higher osmotic
concentration reduce
Osmotic
2. concentration freezing point means
of cell less change for cell to

Low conc → low resist. High conc. → high resist. freezed

Low permeability of cell Higher permeability,

Permeability
of cell to membrane (+ cell wall) water move out
3.
water toward water induced more readily of cell
low water resistance during freezing

High perm high resist

4.
Water binding Colloids bound
Low concentration of
colloids. Higher → higher water molecules, so
colloids = low resistance
(pentosans, it is not easily

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 mucilage & available to freezing
pectin
substance)

Smaller cells are

more hardy than
5. Size of cells larger due to their
small volume
Smaller size  higher surface ratio
resistance.
Larger size  low resist.

EXAMPLES :
1. Frost hardy spp : Conifers, Dalbergia sissoo etc.
2. Frost tender spp : Acacia nilotica, Azadirecta india etc.

10.3 | HIGH TEMPERATURE

All physiological activities in plants take place within an optimum range of temperature.
When temperature increases above this range, all physiological activities are adversely affected
and when temperature increase further plants may die. Ability to resist and adopt high
temperature is very with plants to plants.

EFFECTS OF HIGH TEMPERATURE ON PLANTS :

1. Rate of photosynthesis decrease.

2. Rate of respiration increase
3. Coagulation of protoplasmic protein due to high temperature.
4. Plant is starved and become more susceptible to attack by pathogen.
5. Sunscald & sunburn of seedlings.

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10.4 | WATER LOGGING

When the water content of the soil will exceeds then

its field capacity, the soil is said to be waterlogged. Under
waterlogging condition, all pore spaces are filled by water
resulting in soil atmosphere become anaerobic.

 In water logging, condition plants show symptom of

mineral deficiency.

EFFECTS OF WATER-LOGGING ON PLANTS :

 Plants roots don’t get oxygen

 Anaerobic soil bacteria reduce nitrate and sulphate into ammonia & hydrogen sulphide,
these gases are toxic and killed the plants.
 Mineral absorption reduces due to low availability of respiration energy.

SPECIES THEY GROW IN THIS CONDITION :

1. Eucalyptus spp.,
2. Syzygium cumini,
3. Terminalia arjuna,
4. Acacia niloti

10.5 | HIGH SALT CONCENTRATION

 Salinity adversely affects plant growth due to following reason.

 Salt-tolerant plant = HALOPHYTES.

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 Effects of salinity

Osmotic effects Ionic effects

 In normal soil condition:  The chlorides & sulphate of sodium

Osmotic pressure = ↓ -1 bar, and magnesium are present in large
quantity and plants absorb these ions
But in high salt condition:
in large quantity
O.P. = ↓ -10 to -20 bar,
 Result:
 RESULT : make water absorption 1) Excess amount of Na+ & chloride
more difficult so plants suffer induce toxic symptom (chlorosis,
from water deficit. necrosis etc.)
 Also know: Osmotic stress or 2) Induced premature senescence
physiological stress of older leaf.
3) Due to high Ph, make other
Note : This type drought is not due element less available form
to non availability of water but due to 4) Reduce synthesis of amino acids
& protein. So retard growth.
inability of plants to absorb water

MECHANISM BY WHICH PLANTS DEVELOP RESISTANCE :

a) Pump excess ions out of root by the help of membrane bound protein(mainly in non
halophytes plants)
b) Storing of excess salt and converting into non toxic form
c) Secreting excess ions by salt glands in mangroves leaves
d) Desert saltbush (Atriplex spp.) cover with salt hairs in which
salt is accumulated
e) Some plants accumulate salt in their cell vacuoles until the
concentration of salt is too high that the leaves can absorb no
more salt and ultimately die.

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72
 Mangrove plant leaf with
SALT GLANDS and SALT HAIRS in Atriplex
salt glands

SALT REGULATION IN MANGROVES

Mangroves have 3 methods to regulating their internal salt level :

 EXCLUSION : They have special types of membrane in the roots. Those effectively block
salt uptake and only allow water to enter into the plant
 SECRETION : secret salt via. Special glands in the leaves
 SEQUESTRATION : salt concentrated in bark & leaves which the plants later drops
Example : Avicennia - Leaves turned yellow & drop off when loaded with salt

10.6 | EXERCISE

 2014 : Explain the survival strategies of the following group of plants (20 m).
(a) Halophytes, (b) Phraetophytes (c) Xerophytes (d) Succulent
 2015 : Explain the term Hardning off. What are the internal factors affecting forest resistance ?

Linked QUESTIONS :

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73
 2015 : Why is saline-alkaline soil considered problematic ? Can you suggest any procedure to make
it suitable for plant growth ? (10 m).
 2013 : what are the specific problem of the following wastelands ? suggest at least three species for
planting in each of them (5 m).
1. Hot desert
2. saline and alkaline soils
3. Wetlands
4. Cold desert
 2012 : Comment critically on the following – Failure of forest plantations (5 m).

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74
 Topic 11 FOREST SUCCESSION

CONTENT :

1. Concept 6. Stages in Succession

2. Definition 7. Various types in primary succession
3. Process of succession 8. Theories
4. Types of Succession 9. Importance
5. Causes of succession 10. Exercise

11.1 | CONCEPT

Suppose the forest department went mad in Madhya Pradesh and it cleaned ≈ 100 hectare
forest area for corruption, Even so cruel that they cleaned and sell the upper subsurface soil to Brick
Killen factories, you are a local person who affected by this act and filed case in Supreme Court. In its
verdict, Supreme Court asks them (Forest department) to leave this area permanently on the name
of god. As i said before you are a neighbor of this site, you see that after the onset of monsoon there
where a small patch of grass start growing on a clean barren land, which later die at the end of the
monsoon. You also observed that there were few seeds of shrubs and Teak also germinated but they
failed to establish due to very poor Organic matter and low Minerals availability. These initial grasses
actually did not get any previous Organic material and free minerals from the soil and struggling hard
to mobilized them resultant poor nutrition and small height.
 In next few year’s, these grasses generate bulk of Organic matter and improve soil fertility
that show in its large size and composition (from seasonal grasses to annual grasses). In these new
changed conditions, our shrub species that earlier failed to established not become able to
established and flourished, However Teak still unable to survive as now it germinate and established
but soon die after monsoon end. Subsequently shrub species compete out grasses and field become
from grassland to shrub land.

In next few year’s, these shrubs further enriched the soil organic matter, mobilized soil
minerals and improve soil water holding capacity by further pulverize them. Now the seedling of
Teak that failed to survive in earlier stages now starts dominating the area.

MORAL OF THE STORY :

 1st species that encroach and start to grow in new area – called = COLONIZER.
 Species those established them shelves 1st time in this area = PIONEER spp.
 The process of development and movement of vegetation from one stage (grass land
to tree land) – called = SUCCESSION.
 When COLONIZER start grow on barren land where there No any residue of previous
Organic matter – called PRIMARY SUCCESSION (If grow on previous OM – SECONDARY
SUCCESSION).
 Last tree land or forest stage is - called = CLIMAX condition.

11.2 | DEFINITION

 Succession is the process of replacement of one set of biotic community by another set
of more advance and different nature biotic community.
 Term : Hault
 With every stage in succession complexity and diversity increases.

11.3 | PROCESS OF SUCCESSION

 NUDATION : the process of development of a bare

area (without any form of life), it may be due to
erosion (Soil/water), Volcanic eruption, forest fire,
erosion and deposition etc.

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  INVASION or MIGRATION : migration of seeds & spores

 COLONIZERS : the species which invade/ occupy the new site 1st time.
 POINEER Spp. : the species which grow in the area for the first time

 ECESIS or ESTABLISHMENT : the process of establishment of plant into new area from
its germination to reproduction.

 AGGREGATION : After ecesis, as a result of reproduction the individuals of

species increases in numbers and they come close to each other called
aggregation

 COMPETITION : after aggregation, increasing population creates conflicts

(competition) for light, space, moisture and nutrient minerals. They affect each other’s
through various ways and this action is called CO-ACTION with results REACTION.

 CLIMAX or STABILIZATION stage : FINAL stage

11.4 | TYPES OF SUCCESSION

BASED ON THE STARTING OF SUCCESSION :

 PRIMARY SUCCESSION : when the process of succession start on a land there were
no any previous organic matter, so rate of succession id slower.
Example : Nudation of land after heavy landslide.

 SECONDARY SUCCESSION : succession process start on field where there previously

available organic matter present, so rate of growth is fast.
Example : Succession process after forest fire.

BASED ON NATURE OF SUBSTRATUM :

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  XERARCH SUCCESSION : when succession (especially primary) starting on dry rock
material, windblown send, mineral matter under extremely dry condition.
 MESARCH SUCCESSION : when succession begins with moist and well aerated soil
material.
 HYDRARCH SUCCESSION : when succession process starts with water or very wet
lands i.e. Pond, lakes, marshes etc.

BASED ON THE CAUSE OF SUCCESSION :

 AUTOGENIC SUCCESSION : after the succession has begun, community modified itself
and own environment and replace own by new community. Means there were no
any external interference i.e. Amazon rain forest.

 ALLOGENIC SUCCESSION : when replacement of one community by another due to

external forces.
 INDUCED SUCCESSION : when human activities are responsible for the succession of
a plant community i.e. Keoladev Ghana bird sanctuary where formation of wetland
and whole ecosystem started after dam formation in mid 18 th century.

NOTE : CYCLIC SUCCESSION : is a pattern of vegetation change in which in a small number of

species tend to replace each other over time in the absence of large-scale disturbance.
Cyclic replacement has provided evidence against traditional Clementsian views of an
end-state climax community with stable species compositions.

 RETROGRESSIVE SUCCESSION : when natural

succession is obstructed by natural or biotic factors and
push few stages back called retrogressive succession
i.e. SAL FOREST converted into SAL SAVANNAH in Uttar
Pradesh due to heavy biotic pressure (over grazing,

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 shifting cultivation etc.)

11.5 | CAUSES OF SUCCESSION

 INITIATING CAUSES : to make space (NUDATION) or bare area for new succession
process by destroying the existing once through climatic or biotic factors i.e. Land
sliding, soil erosion & deposition, volcanic eruption, long term water logging,
deforestation, Forest fire, coastal and estuarine deposition.

 CONTINUATION CAUSES : that continue the movement of succession process

through various seral stages i.e. Migration, ecesis, aggregation, competition, reaction
etc.

 STABILIZING CAUSES : they finally established the colony according to the local area
climate, soil or complex of factors.

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IFoS 2011 : Describe the initial causes of secondary succession. Write various seral stages
of succession leading to the development of Shorea robusta.

Solution : Initiating causes are the disturbances that make space or bare area by destroying
the existing forest vegetation for initiate secondary succession. In this process
new sucession usually used pre-existing Organic matter of previous crop, They
may be following –

 Climatic causes : Drought, flood, heavy snow and frosty conditions

 Physiographic factors i.e. soil erosion
 Biotic causes : Forest fire due to carelessness, insect-pest destroyed entire
vegetation of an area.

MODEL : Describe the initial causes of SECONDARY succession.

Solution : Initiating causes are the disturbances that make bare soil or NUDATION by either
originating new surface area by heavy land sliding and thick soil layer deposition
over the plain or by destroying the existing forest vegetation with its humus.

 Long-term persisting flooding

 Heavy surface soil erosion and deposition
 Formation of new lava plains after volcanic eruption
 Biotic factor ? no because they destroyed forest but not humus

MODEL : Causes of retrogressive Succession ? .

Solution : Same as we study earlier 4 factors – Climatic, edaphic, biotic and physiogrphic.

 Climatic : Drought, flood, insect-pest attack

 Physiographic : Land slide
 Man-made : Shifting cultivation, fire, lopping

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11.6 | STAGES IN SUCCESSION

NOTE : here we gives just conceptual part, usually they didn’t asked this in this way. They asking its
application like in 2011 they asked Write VARIOUS SERAL STAGES of development of SAL forest or
SUB-CLIMAX in 2017.

 PIONEER : the initiation phase, when few species established themselves in a newly
formed soil.
 SERE or SERAL STAGES (sometime used term CONSOLIDATION PHASE in lose sense)
are the intermediate stages during which plant community grow and improving soil
condition and gradually change themselves into another more advanced community.
 SUBCLIMAX : it is the immediately preceding stage of climax in an ecological. It is
relative stable, and maintain by edaphic or biotic influences or by fire.
 CLIMAX : A mature final and stable community that maintain itself for long period in
equilibrium with that particular environmental condition.
 POST CLIMAX : is a strip of vegetation of higher life form occurring within a climatic
climax.

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11.7 | VARIOUS TYPES OF PRIMARY SUCCESSION

 Riverine Succession
 Esturian succession
 Succession in Mountain temperate Forest
 Succession in sand dune condition
 Succession in Hydrarch, mesarch, xerarch condition

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11.7 | VARIOUS THEORIES FOR SUCCESSION

 MONO CLIMAX THEORY or CLIMATIC CLIMAX THEORY :

₋ Given by FE CLEMENT
₋ According to this theory only climatic condition involved into controlling succession
so there are only one type of climax community formed.

 POLY CLIMAX THEORY :

₋ By Tansley
₋ Counter of Clement theory, TENSELY suggest climax community is never actually
controlled by single factors.
₋ This theory considers that the climax vegetation of region consists of not just one
type but a mosaic of vegetational climaxes controlled by soil moisture, nutrients,
topography, slope, aspect, fire, grazing, etc. According to this concept, each stable
community within a climate is called a climax community.
₋ When the development of communities are due to Climate, they are described as
CLIMATIC CLIMAX, when it is due to -
Edaphic conditions → EDAPHIC CLIMATE
Biotic disturbances → BIOTIC CLIMAX
or due to topography where dominant factor → TOPOGRAPHIC climax

EXAMPLES :
 CLIMATIC CLIMAX : Giant evergreen forest in Andaman and nicobar
 EDAPHIC CLIMAX : Babool forest in black cotton soil, Butea forest in Badly drained soil
of central India.
 BOITIC CLIMAX : Tropical moist deciduous forest of teak in Laterite soil replaced by
Xylia xylocarpa due to biotic interference.

 INFORMATION THEORY :
₋ By Fosberg (1967) and odum (1969)
₋ According to this theory succession is a function of energy balance and nutrient
cycles. The climax stage is reached when the amount of energy and nutrient

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 received from the environment by the vegetation is again returned in more or less
similar amount to the environment by the decomposition through heterotrophs.

 CLIMAX PATTERN HYPOTHESIS :

Whittaker (1953) emphasized that a natural community is adapted to the
whole pattern of environmental factors in which it exists; the major factors are:
genetic structure of each species, climate, site, soil, biotic factors (activity of
animals), fire, and wind, availability of plant and animal species, and chances of
dispersal. According to this theory, climax communities are patterns of populations
varying according to the total environment. There is thus no discrete number of
climax communities and no one factor determines the structure and stability of a
climax community. Whereas the mono-climax theory allows for only one climatic
climax in a region and the poly-climax theory allows several climaxes, the climax-
pattern hypothesis allows a continuity of climax types varying gradually along
environmental gradients and not clearly separable into discrete climax types.

11.8 | IMPORTANCE OF SUCCESSION IN SILVICULTURE

The study of succession in silviculture is important as it helps foresters in

1) Classifying the forests

2) deciding the silviculture system to be adopted for the management of the
existing crop,
3) selecting suitable species and site treatment for artificial regeneration and
4) deciding silvicultural operations to maintain the forests at a desired
successional stage.

In classification of forest types, one of the important considerations is its ecological

status and Indian forests have been classified on this basis. Various stages in succession e.g.
climax, seral and retrograde, secondary succession, etc. Are recognised. The knowledge of
succession of the forest helps to decide suitable system of management. For climax
vegetation, the silviculture system should be such which creates least disturbance. Selection
system favours the development of climax species and systems with heavy fellings may be
good for seral or pre-climax species. The choice of species and soil treatment practices are

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somewhat related to forest succession. For immature soils, usually seral or pre-climax
species need to be selected. The climax species are suitable for mature soils. The soils which
are immature or recent in origin are usually deficient in organic matter and nutrients.
Addition of organic matter and fertilizers ensures success in artificial regeneration. If some
economically import ant species occur in seral or preclimax stage, the same can be
maintained at that stage, through control on biotic fạctors, e.g., clearing, tire, grazing, etc.

11.9 | EXERCISE

 2017 : what is SUB-CLIMAX ? Explain its importance in the context of Indian forestry (10 m).
 2017 : Explain various TYPES OF SUCCESSION. Describe the major theories explaining succession
(10 m).
 2014 : Discuss in detail the EVOLUTION OF THE CONCEPT of plant succession (20 m).
 2013 : Explain the evolution of the concept of plant succession (8 m).
 2012 : IMPORTANCE of plant succession in Forestry practices.
 2011 : Describe the INITIAL CAUSES of SECONDARY succession
 2011 : Write VARIOUS SERAL STAGE of succession leading to the development of SAL forest.
 2008 : what is succession ? explain in details the different TYPES of succession, describe the
major THEORIES explaining succession (20 m).
 2007 : what is succession ? Describe primary and secondary succession along with examples,
how the succession is STUDIES IN NATURAL FOREST (20 m).
 2007 : Describe the process of typical SUCCESSION IN XERIC condition.

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 Chapter 12 FOREST TYPES IN INDIA

Forest type is a category of forest definedd with reference to its geographic allocation,
climatic and edaphic features, composition and condition. Champion and Seth defined it as -"a unit
of vegetation which possesses (broad) characteristics in physiognomny structure sufficiently
pronounced to permit its differentiation from other such units".

IFoS 2012 : Basis of forest classification and why there is need for such classification

12.1 | BASIS OF CLASSIFICATION

Various factors which form the basis for classification of forests into various forest types
include :

(a) physiognomy,
(b) structure,
(c) function,
(d) floristics,
(e) dynamics
(f) environment and
(g) history

 PHYSIOGNOMY : It is an art of judging character from features of face, or form of body.

From general appearance, forest can be classified into : (a) evergreen or deciduous, (b)
broad leaved or coniferous, (c) consisting of large trees or small trees, shrubs, herbs or
grasses.
 STRUCTURE : Structure means stratification in forests, dimensions especially height and
spacing. Forests on this basis can be classified into: (a) single storeyed, (b) double
storeyed and (c) multi-storeyed. On the basis of spacing, a forest is (a) closed, (b) dense,
(c) thin and (d) open.
 FUNCTION : It covers the common morphological characters of the species, such as form
of stem, leaf, bark, etc.

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 FLORISTICS : Floristics means the species composition in the forest which is considered
useful for determination of minor types and units within a forest type e.g. pure forests
or mixed forests.
 DYNAMICS : Dynamics refers to the consideration to mutual interaction in forest
communities and the habitat. On this basis, forest may be identified to be in
successional stages or on its climax.
 ENVIRONMENT : Environment or site refers to the climatic, edaphic, physiographic and
biotic factors. These factors are often used in identification of various types and sub
types.
 HISTORY : History of a site and the vegetation are also important in determining the
pregent and assessing the future productivity.

12.2 | CRITERIA FOR DELIMITING FOREST TYPES

Though, various plant communities Constitute the floristic composition of the forest,
but it is the tree layer which is more important for identification of forest type. Various
factors which affect trees and forests are climate, soil, physiography, microclimate and biotic
factors. These factors have been used in classifying forests.

 FOREST TYPES IN RELATION TO CLIMATE : Climate is a very important factor in the

classification of forests. Vegetation all over the world has been classified purely on the
basis of climate by several workers. The most important variables of climate, e.g.
temperature and rainfall have been used in classifying forests. The effect of temperature
and rainfall on forests have already been discussed under climatic factors. On the basis
of mean annual and mean January temperatures and occurrence of frost and snow, etc.
four temperature zones have been recognised. These are: (i) tropical, (ii) sub-tropical,
(iii) temperate and (iv) alpine. Indian forests have been classified into these zones.

The rainfall is another important factor in the classification of forests. On the

basis of rainfall, forests are classified into; (i) wet, (ii) moist, (iii) semi-moist, (iv) dry and
(v) desert types. (i) Wet forests include forests occurring in areas having mean annual
rainfall over 2500 mm. (ii) Moist and semi-moist forests occur in areas where mean
annual rainfall is between 1250 mm and 2500 mm. (iii) Dry forests are located in areas

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 having rainfall between 750 mm and 1250 mm. (iv) Desert forests are found in areas
with rainfall below 750 mm. Temperature and rainfall together are also used to classify
forests. Several factors, e.g. precipitation-effectiveness-index, evapo-transpiration ratio,
moisture indices, etc. have been used to classify forests. Precipitation-effectiveness
index is the ratio of precipitation to evaporation. Evapo-transpiration is the sum total of
evaporation and transpiration. These factors are not easy to work out as we do not have
enough observations on various climatic factors for seyeral locations. Therefore,
classification of forests on the basis of temperature and rain fall is more popular.

 FOREST TYPES IN RELATION TO SOIL : Soil affects the forest within the prevailing
climate. Several factors of soil have pronounced effect on the forest type. Physical
characteristics e.g. sandy and clayey nature, recent alluvial and old mature soil, well
drained and water-logged, saline-alkaline, neutral and acidic soils, different soil depths,
etc., bear different types of forests. For example, khair and sissoo forests are associated
with recent alluvial soils. Acacia nilotica forests are common in clayey and black cotton
soils. A large number of species grow well only in well drained soils. Only a few species
are found adapted to water logged soils. Similarly, only a limited number of species e.g.
Prosopis, Acacia, Tamarix, etc. grow in saline-sodic soils, while most species prefer
neutral or slightly acidic soils.
Due to these influences we find several edaphic forest sub- types in various
climatic forest types. For example, ateritic forest sub-type in semi-evergreen,
Anogeissus pendula forests, Boswellia forests, babul forests, Butea forests, Aegle
forests, etc. in dry deciduous types, palm swamps in littoral and swamp forests,
Euphorbia, Acacia senegal and Salvadora forest sub- types in thorn forests, Cypress
forests in Himalayan moist temperate forest, etc., are some of the typical edaphic forest
types.

 FOREST TYPES IN RELATION TO PHYSIOGRAPHY : The role of physiographic factors viz.

altitude, slope, topography, aspect and soil cover on the vegetation is quite pronounced
through their effect on the climate and soil. Among topographic factors, perhaps the
most important factor is the altitude. Forest types are usually identified on the basis of
altitude. For example, sub-tropical pine forests in Himalayas are classified into two sub-
types: (i) lower chir pine forests occurring below 1000 m altitude and (ii) upper chir pine

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 forests occurring above 1000 m altitude. Similarly, temperate forests of western
Himalayas are classified into: (i) lower western Himalayan temperate forests consisting
of ban oak and moru oak occurring below 2500 m elevation and (ii) upper Himalayan
temperate forests consisting of kharsu oak, fir and spruce occurring above 2500 m
elevation. When a species occurs in a comparatively large altitudinal range, it is usually
easy to distinguish between sub types. Aspect is perhaps another factor which affects
the development of different types of forests as southern and western aspects are
always hotter than northern and eastern aspects.
 FOREST TYPES IN RELATION TO BIOTIC FACTORS : Uncontrolled grazing and fires, heavy
illicit fellings, epidemic out-breaks of insect pests and diseases are some of the
important biotic factors, which control the development of forests. These factors
degrade the forest considerably. Unrestricted grazing and uncontrolled fire may destroy
the forests and push the vegetation several stages back in the succession. Several
degradation torest types are identified which are a result of these biotic factors. For
example, Himalayan sub-tropical scrub and sub-tropical scrub forests in sub-tropical
pine forest types, wet scrub forest sub-type in wet temperate forests, oak scrub and
Himalayan temperate scrub in moist temperate forest types are some of the typical
degraded sub-types.

12.3 | ORIGIN OF INDIAN FLORA

Indian flora is a mixture of the following elements:

(a) Malayan flora,
(b) European and Mediterranean flora
(c) African or Indo-African flora
(d) Tibetan and Siberian flora
(e) Chinese and Japanese flora
(f) Australian flora.

(a) The Malayan flora consisting of Dipterocarpeae, Dilleniaceae, Schleichera, Garcinia etc.
are found in high rainfall areas particularly in eastern and southern states of the
country.

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(b) The EUROPEAN and MEDITERRANEAN FLORA is represented by Coniferae, Betuleae,
etc., which mostly occur in Himalayas.
(c) The AFRICAN and INDO-AFRICAN FLORA consists of various species of Acacias and some
other plants of Leguminosne Combretaceae and Rhamnaceae. These are found
distributed in almost all tropical areas, particularly in the drier areas.
(d) The TIBETAN FLORA consists of alpine herbs and shrubs which are found in Himalayas.
(e) The CHINESE AND JAPANESE FLORA includes many species of Quercinaceae,
Ternstroemiaceae, (e.g. Schima)a Rhododendron, Altingia, Tsuga, etc.
(f) The AUSTRALIAN FLORA is represented by Casuarina, Helicia, etc. in coastal areas in
India.

12.4 | BOTANICAL AREAS

A number of botanical areas have been recognised in the country. These botanical areas
have have characteristic botanical features. important botanical areas in India are as
Follows :
 WESTERN HIMALAYAS : This area consists of Himalayan mountains from Kumaon to
Kashmir + annual precipitation of 1000 mm to 2500 mm. The western Himalayan region
consists of Siwalik bhabar tract have mainly Shorea robusta forests. In the montane
subtropical areas, forests of Pinus roxburghii are of considerable economic importance.
In the montane temperate zone, coniferous forests of Cedrus deodara, Pinus
wallichiana, Picea smithiana and Abies vindrow occur sometimes in pure and mostly in
mixture.
 EASTERN HIMALAYA : Eastern Himalayas constitute the humid regions from Sikkim and
eastwards, characterised by heavy rainfall, scanty snowfall and high temperature and humidity.
The tropical zone consists of mainly sal forests (with patches of riverain forests). The evergreen
forests are composed of Artocarpus, Michelin champaca, Dendrocalamus hamiltonii,
etc.
 INDUS PLAIN : This region comprises parts of Punjab, Rajasthan, Gujarat and Delhi with
annual rainfall usually less than 800 mm. The forests in this region are degraded by
biotic interference. They consist of mainly bushy and thorny trees belonging to the
genus Acacia, Prosopis, Anogeissus etc.

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 GANGETIC PLAIN : This region consists of Uttar Pradesh and parts of Bihar, Orissa and
West Bengal. Important species - Shorea, Terminalin, Lagerstroemin, Bauhinia etc. The
mangrove forests of Sunderbans and delta forests in Bay of West Bengal are special
forms of flora in this area.
 CENTRAL INDIA: This region consists of mainly Madhya Pradesh. The hill ranges are
generally formed by granite and gneiss The important species occurring in this region
belong to genus Tectona, Madhuca, Terminalia, Lagerstroemin, Bauhinia etc.
 WEST COAST : areas of heavy rainfall = Luxuriant vegetation = mostly tropical evergreen
and mixed moist deciduous forests. Species : Toona, Desoxylum, Dipterocarpus, Hopea,
Mesua, Mangifera, Sterculia, Calophyllum, Artocarpus etc. The sub-tropical and
temperate evergreen forests which are commonly known as SHOLAS occur in Nilgiri and
Annamalai hills.
 DECCAN PLATEAU : includes the major part of the Indian peninsula, where the forests of
Tectona, Hardwickia, Boswellia, Terminalia, Anogeissus, Schleichera etc. Karnataka has
valuable forests of Santalum album.

12.5 | CHAMPIAN AND SETH CLASSIFICATION

Champion and Seth (1968) classified the forests of the country into various forest types on the basis
of ecosystem approach and taking into consideration vegetation, climate, soil and other habitat
factors.

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Limitations of Champion and Seth's classification

The system of classification of Indian forests into different forest types has been
widely adopted. But the classification is not complete in itself. There are certain forest
associations which have not been mentioned at all. The system suffers from the following
limitations.

1. The classification of forests of India into different forest types is generally based on
observations here and there and the forest type map of India is approximate. No
systematic survey has been conducted. Division of area into different forest types is
done arbitrarily. Identification of floristic composition in different forest types would
have been done in better way if stock maps or aerial photographs would have been
used for the purpose.
2. Certain forest formations have not been included in the classification i.e. (a)
Chloroxylon swietenia which occurs as under storey tree in dry and very dry teak
forest types, forms almost pure crop where soil conditions are not favourable. (b). In

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 certain areas of Madhya Pradesh, sitaphal (Anona squamosa) is the main vegetation
on ridge tops where the soil is very poor and lateritic. Presence of Kankar nodules is
obvious. (c) Moist mixed deciduous forests occurring in the south of Brahmaputra
river (Assam), which have about 15 per cent sal, are not covered in any of the type
and sub-types.
3. The area under man made forests is increasing day by day. But, Champion and Seth's
classification covers only natural vegetation. No system of classification is involved
for artificially raised forests.
4. Many new species have been introduced and are being regenerated naturally. Natural
barriers of many species have been broken. Teak has been introduced in forests of
north india. Chir (Pinus roxburghii) has done well in artificially raised plantation in
Supkhar area (Balaghat of Madhya Pradesh).
5. The forests of Jammu and Kashmir and Sikkim have not been included in the
examples.
6. Floristic composition in dry sub tropical forests and dry temperate forests does not
compare favourably with examples, specially so of Bastar district of Madhya Pradesh.

12.6 | NEEDS OF FOREST CLASSIFICATION

2.3 | EXERCISE

 2017 : Enlist four groups of forest types under the moist tropical forest as per the Champion and
Seth classification of forest types (8m).
 2012 : Basis of forest classification and why there is need for such classification.

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 Chapter 13 NATURAL REGENERATION

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 IFoS 2012 : Successful regeneration in a forest depends upon silvicultural." system. (5m)
 2013 : Large scale mortality has been noticed in Dalbergia sissoo and Acacia nilotica
What could be the possible reasons for this mortality? (10)
 2012 : Reasons of dying Dalbergia sissoo (5m)

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 IFoS 2017 : Give four examples of uses of Pollarding in Indian forestry (8)

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 IFoS 2014 : Describe the following : regeneration survey (5 m)

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EXERCISE : Natural regeneration + Artifiial regeneration

 2018 : no
 2017 : Give four examples of uses of Pollarding in Indian forestry (8)
 2015 : Comment upon the dieback (dying back) phenomenon in Shorea robusta. Is it a problem
or a adaptation ?

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 Chapter 14 ARTIFICIAL REGENERATION

IFoS 2014 : Discuss in detail the objectives of artificial regeneration (10 m)

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FEATURES OF PLANTATION

Plantations are man made and have the following important features :

 SPECIES COMPOSITION : Almost all plantations are grown in monoculture because

planting operation and subsequently management are much simpler with monoculture
plantations. Sometimes 2 or 3 species are mixed in plantations. The mixture is either
by block or by strips or lines.
 AGE : Plantations are even aged. All the trees in the plantations are almost of the same
age. The even aged stands are simple. When plantations start regenerating naturally
some unevenagedness may be introduced in the crop.
 STOCKING : Initially, plantations do not occupy the site fully. It takes quite a long
period about 5 to 10 years to occupy the site fully. The stocking can be manipulated by
adjusting the spacing in plantation. Generally, stocking can be referred to yield or
stand table numbers. Where the number of trees at planting are below these figures,
the plantation can be said to be understocked.
 CANOPY : Usually, plantations should have a single layer however, some difference is
introduced in the crop due to various factors and the height and diameter growth of all
the trees are not the same. The crop however cannot be called having multilayered .

INSHORT :

2013 : Explain various factors affecting the choice between artificial and natural
regeneration with reasoning ( 10m)
2012 : Differentiate clearly between natural and artificial regeneration of forests. Describe
the manner in which natural regeneration of Teak, Sal and Deodar takes place

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ARTIFICIAL V/S NATURL REGENERATION

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FACTORS AFFECTING PLANTATION ACTIVITY

 FINANCE : one of the most important consideration in deciding the rate of plantation.
There are three main sources of finance, (a) Local state government or governntent of
India, (b) International funding agencies and (c) Commercial banks. Most of the funds
for plantations are coming up from local state government or government of India
sources. Now CAMPA fund + 2% share of project cost under green highway corridor.
International funding agencies like World Bank, USAID, SEDA etc.
 LAND : Land must be available in large chunks for raising plantations. The land should be
made available to the planting organisation 1 to 5 years in advance to carry out
preliminary surveys and other pre-plantation works. Availability of land in small pockets
creates supervision problem and increases plantation cost.
 LABOUR : Plantation activity is labour intensive and therefore, sufficient labour both
trained and untrained should be available for raising plantation.
 INFRASTRUCTURE : Several other infrastructures such as nurseries, roads, workshops,
transport facilities, housing etc. are required. Without these infrastructures plantations
on a large scale is difficult.
 MARKETING AND PRICING : The main purpose of raising plantation is the production
either firewood or timber or pulp wood. Several times market conditions change which
leads to the change in the utilisation pattern. If market support is available, the
plantations become self sustaining.
 SOCIAL AND CULTURAL FACTORS : Social and cultural factors also affect the rate of
development of plantation. Local demands adversely affects the industrial plantations .

Do ‘Russian poplar’ seeds cause May illness in Kashmir?

Over the years, people in the Valley have started to prefer the “Russian poplar” over the native
Kashmiri poplar for its quick growth — 10-15 years to reach full size compared to 30-40 years for
the Kashmiri poplar. It was introduced in Kashmir in 1982 under a Word Bank-aided social
forestry scheme. The tree is a Western American species known as Eastern Cottonwood
(Populus deltoides) in the US. In May every year, hospitals and doctors in the Kashmir Valley find
themselves treating a high number of patients, especially children, with respiratory diseases.
The patients complain of sore throat, cold, cough and fever. While a common cause is pollen

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 shed by various plants, the spike in illness has often been attributed to a phenomenon during
this season.
Result : In 2014, J & K High Court banned sale, purchase and plantation of the female “Russian
poplars” in Srinagar.
https://indianexpress.com/article/explained/do-russian-poplar-seeds-cause-may-illness-in-
kashmir-the-fears-the-science-5724268/

PLANTATION ORGANISATION

The plantation activity requires a great deal of organisation and planning. A number
of operations are required to be performed in a plantation programme. Some of the
important activities relating to plantations are as follows :

(i) Seed collection and storage

(ii) Identification of land where plantation is to be raised
(iii) Nursery operation for raising planting stock
(iv) Pre-plarıting activities
(v) Sowing and planting
(vi) Protection and maintenance
(vii) Tending operations
a. Weeding
b. Pruning
c. Thinning
d. Others
(viii) Rotation and harvesting

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IFoS 2014 : What do you mean by plantation schedule ? give in detail the factors which
decide the success of plantation programme (10 m)

PLANTATION SCHEDULE

One of the key factors for the success of plantations is timely operations. A schedule
usually exists in each state for completion of various activities involved in plantations. The
layout, demarcation, marking, etc. of felling coupe or plantation area should be completed
about one year in advance. Similarly, collection of seed and sowing. in the nursery should
start atleast one to 3 years in advance depending upon the species and size of plants
required. Felling of trees and shrubs in the plantation area should be completed about 6 to 8
months in advance. The trees should be logged and saleable material should be removed
from the coupe, atleast 6 months in advance. The disposal of slash and debris and working of
the soil should be completed by April-May and the plantation should start as early as
possible after the onset of monsoon. After planting is over, plantation should be inspected
and the seedlings which have died should be replaced. In the first year 2 to 3 weedings are
done. Thinnings are done after 5 years of age. Plantation schedule for chir, deodar, teak and
bamboo is given in table :

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 IFoS 2012 : Comment critically : Failure of Forest plantations (5)

SUCCESS OF PLANTATION

Success of the plantation programme depends upon several factors. Technical

factors, like selection of right species, correct soil working, proper size of nursery stock,
proper planting technique, etc. are important. Beside these there are several socio-
economic factors which decide the success of the plantation. Some of the important factors
are as follows :

1) Participation and involvement of the LOCAL POPULATION

2) Commitment and the financial provisions by the government over a long period of
time. Change in government should not alter the allotment.
3) Plantation should be done as a part of integrated land use.
4) There should be a competent organisation to carry out plantation. There should be
arrangement for proper training.
5) Infrastructure should be well developed in respect of nursery, seed, store etc.
6) The plantations need to be protected against biotic interference for longer period.
local population.

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 Chapter 15 CHOICE OF SPECIES

CONTENT :-

2013 : Enumerate the factors which decide the choice of species for plantation (8)

15.1 | FACTORS

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2018 : Write the problems and prospects of exotic tree species in India with suitable
examples (15 m).

2016 : Discuss the reasons for widespread use of exotics for plantations and specific
advantages of exotics over native species (8m)

2012 : Comments : Exotics in Indian Forestry (5m).

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EXERCISE

 2018 : Write in brief on the criteria of selection of tree for resistance to adverse
environments for high quality timber production (8m)
 2012 : What are ecological aspects for Selecting the tree species ? Discuss (8m)

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 Chapter 16 SEED SUPPLY

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EXERCISE

 2018 : Explain seed production and certification system in Indian forestry (10 m).
 2014 : Explain the following : Orthodox and recalcitrant seeds (5 m).
 2014 : Exogenous dormancy and endogenous dormancy

Linked QUESTION :

 2014 : Discuss the important factors white planning of seed orchards (10 m) (Tree
improvement subject).

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2006 : Define vegetative propogation and discuss in details the various techniques adopted
in vegetative propagation
2017 : Enlist the advantages and disadvantages of vegetative propagation. What future do
you foresee for it in forestry ?

VEGETATIVE PROPOGATION

Vegetative propagation It is otherwise called as asexual propagation in which the

propagation is predominantly by vegetative means either through plant parts or through plant
tissues.

ADVANTAGES :
 Vegetative propagation helps to produce genetically identical plants.
 Many tree species do not produce viable seeds and some trees do not produce seeds at all.
Such species can be propagated through vegetative means easily.
 Vegetative propagation through grafting helps to produce pest and disease free plants.
 This method eliminates the variability and maintain clonal fidelity.
 It also helps to induce early flowering and reduce the rotation.
  Vegetative propagation helps to accelerate the breeding process and has excellent
application in potted or controlled breeding.
 It is more rapid, uniform and large scale multiplication is economically viable compared to
seed propagation.
 It helps to preserve the geno-type through clonal bank approach

DIS-ADVANTAGES :

 Vegetative propagation is expensive than seed propagation in many species.

 Vegetative propagules lack taproot system and hence prone to damage due to winds and
cyclone.
 Chances of epidemic pest and disease occurrence are more compared to seed propagation.
 It require skill and expectise.

METHODS OF PROPAGATION : usually we refer Artificial neams

A. MACRO VEGETATIVE PROPAGATION

B. MICRO VEGETATIVE PROPAGATION

A | MACRO - VEGETATIVE PROPOGATION

1) Cutting
2) Budding
3) Grafting
4) Layering

1 ) CUTTING : cutting refers to any portionremoved from the parent plant which is meant for
regeneration.
EXAMPLES : Stem cutting, root cutting, leaf cutting, shoftwood cutting, hardwood
cutting etc.

FACTORS AFFECTING ROOTING OF CUTTINGS :

₋ Age of the stock planta

₋ Condition of the cutting
₋ Nutritional and hormonal conditional of the plant
₋ Relative position of the of shoot
₋ Maturity of the tissue

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 ₋ Position of the basal cut with reference to the node.
₋ Effect of leaves and buds
₋ Time of collection of cuttings
₋ Light, Temperature, Humidity, water quality
₋ Rooting media

2) GRAFTING : art of joining plant parts together in such a way that they will readily unite and
continue to grow as one plant.

FACTORS CONTROLLING THE SUCCESS OF GRAFTING :

₋ Compatibility of graft union

₋ Closeness of fit
₋ Cambial contact
₋ Time of grafting
₋ Growing condition
TYPES OF GRAFTING :

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3) LAYERING : in which a portion of an above-ground stem grows roots while still attached to
the parent plant and then detaches as an independent plant.

4) BUDDING : in which a bud of one plant transplanted on anather plant.

B | MiCRO - VEGETATIVE PROPOGATION

By using tissue culture techniques

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NURSERY CALENDER

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NURSERY REGISTER

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EXERCISE

 2018 : Enlist different types of nurseries and write different types of nursery beds used
in a nursery
 2018 : Enlist different types of containers used in a forest nursery and explain different
methods of seed sowing followed in a nursery
 2015 : Describe the methods of pre-sowing treatment of seeds for raising Nursery (10).
 2015 : Explain the necessity of grading of seedlings before plantation (10 m)
 2011 : Explain the following points in relation to nursery management. (4*5 = 20 m)
1) Site selection and layout
2) Soil working
3) Methods of raising nursery stock
4) Plant protection measures
5) Nuresery register
 2010 : What are the different types of containers used in raising forest nursery ? List
their advantages and disadvantages (5)

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EXERCISE

 2017 : Calculate the number of seeds required to raise a 20 hectare plantation with 4 m
x 4 m spacing and an extra plant in the centre of each square. Plant percent of the
species is 75%.
 2016 : write the importance of soil organic matter in forest. How is calculation of
number of seedlings carried under line, square, triangular and Quincunx methods of
planting (20 m).
 2012 : Highlight the salient features of – (2x3=6)
1) Aerial seeding
2) Stump planting.
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 Chapter 20 AFFORESTATION OF DIFFICULT SITES

CONTENT :-
1. Hot deseart and shifting sand dunes
2. Saline alkaline area
3. Ravine land
4. Cold desert
5. Lateritic soil
6. Coastal land
7. Dry rocky area
8. Wetland
9. Landslide
10. Black cotton soil
11. Mines area
12. Canal side plantation
13. Road side plantation

2012 : Describe the technique of Sand Dune Fixation in the Thar Desert. Also mention the
choice of species for planting.(15 m).

20.1 | HOT DESEART AND SHIFTING SAND DUNES

 DISTRIBUTION : The total area of hot desert in India is 31.7 million hectares 61 per cent
of which Iies in Rajasthan.
 LOCALITY FACTORS : Mean annual rainfall = 100 mm to 450 mm. The rainfall in these
regions is erratic and droughts are frequent.
 TEMPERATURE : 48 °C in may-june to 15°C, even
sometime goes below freezing point at several
places.
 WINDS : 100 to 150 km per hour are
experienced during summer.
 SOILS : sandy characterised with well developed
hard pan of calcium carbonate at varying
depths. Desert soils are purely mineral soils obtained by mechanical
disintegration of rocks. Characteris : (i) very low organic matter, (ii) high
 percentage of sol- uble salts, (iii) low nutrient status particularly nitrogen, (iv)
high pH and calcium carbonate, (v) structureless and coarse textured, (vi) very
poor water holding capacity and (vii) absolute deficiency of soil moisture.
 Heavily populated (61 persons /km2 as against 3 persons /km2 of the world
average) + Livestock population
 Sand dunes : dominant formation, ≈ 60 % of the desert area of the western
Rajasthan is covered this.
 ISSUES :
₋ Seeds fail to germinate in the unstabilized wind blown sand and often seedlings
get buried by drifting of sand.
₋ Soil + hard pan (Remember all 4F)
 SOLUTION : (Soil working ) by 2 way
1) Erecting micro windbreaks across the wind directive in parallel strips or in
checker board design by using local available plant material and

2) revegetating the sand dunes by planting the seedlings or sowing seeds.

 PLANTING MATERIAL :
₋ Rooted cuttings of 60 to 80 cm length + Deep planting protects the planting stock
against deflection.
₋ Brick prantation
 SUITABLE SPECIES : Acacia tortilis, Prosopis chilensis

2012 : Give suitable forestry techniques for the reclamation of salt affected soils

20.2 | SALINE ALKALINE AREA

 DISTRIBUTION : 7 M hac.
 LOCALITY FACTORS : (a) arid and semi-arid climate, (b) impervious hard sub-soil due to
clay or kankar pan, (C) basin-shaped topography, (d) high water table, (e) impeded
drainage, (f) salt-bearing sub-strata, (g) excessive canal irrigation, (h) use of saline and
brackish water for irrigation and (i) flooding by sea water.
 ISSUES :
₋ high osmotic pressure due to an excessive concentration of soluble salts

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 ₋ Hard pan = Decreased availability of soil moisture and air
₋ toxicity of sodium salts,
₋ Poor availability
 SOIL WORKING : (a) production of loose soil suitable for rapid root development, (b)
breaking the kankar pan or clay-pan for deeper penetration of roots, (c) production of
soil mass which may facilitate leaching of soluble salts, retention of soil moisture,
draining excess water etc., (d) replacement of exchangeable sodium by addition of
amendments and (e) maintenance of fertility through addition of manures and
fertilizers. (F) pits and trenches of various sizes are used in different states. trench-
ridge method of soil working is better. (G) Addition of 3.5 kg of gypsum and 2.5 kg of
farmyard manure has been found helpful in improving the soil condition = better
survival.
 SUITABLE SPECIES : Prosopis chilensis, Neem, Acacia nilotica.

2012 : Describe briefly the afforestation techniques adopted for Ravinous lands of Yamuna
giving suitable species

20.3 | RAVINE LAND

 DISTRIBUTION : Ravines are network of deep gullies. The whole land mass is cut by a
number of deen gullies. These lands occupy about 6.7 million ha, mainly on the banks
of the rivers Yamuna, Chambal, Mahi and Betwa in the states of Uttar Pradesh,
Rajasthan, Gujarat and Madhya Pradesh.

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  LOCALITY FACTORS :
₋ average rainfall : 75 cm to 125 cm, mostly during the monsoon.
₋ Temperature : 48oC (summer) to Crosses the freezing point in winter = severe frost
also occurs.
₋ The run-off is maximum, slopes are steep and gullies are of varying depths from
few metre to 100 m or more.
 SOIL WORKING : Ravine afforestation has to be carried out on the catchment basis
with other operations of soil and water conservation.
₋ Pluged gullies by the local growing brushwood + soil to control soil erosion.
₋ Check dams + Controur bunding
 SUITABLE SPECIES : Acacia nilotica, Prosopis sineraria, Delbergia sosoo, Acacia catechu
etc.

AERIAL SEEDING

In India Aerial seeding has been carried out in 1980 – 1986 in

cambal valley of central india and in western ghat with aim to
check soil erosion.

SPECIES : Prosopis chilensis, Acacia nilotica, A. catechu,

Dendrocalamus strictus, Albizia lebbeck and Dalbergia sissoo at
the rate of 20 - 40 kg/ha

AIM : -
1) Control soil erosion
2) Provide nutritious pods to wild + domestic animals
3) Increase succession progress

2017 : Where are cold deserts found in India ? Explain site characteristics encountered in a
cold desert and steps suggested to overcome problems in their afforestation (10).

2016 : Write th characteristics of cold desert. Discuss soil working and planting techniques
for cold deseart (8 m).

2014 : Discuss the importance of willow cultivation in cold deseart ( 8m).

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20.4 | COLD DESERT

 DISTRIBUTION : Leh –ladakh + lahut-spiti valley

 LOCALITY FACTORS :
₋ Temperature : snowfall (growing season – 3 to 5 month)
₋ Rainfall : below 60 cm
₋ Soil : sandy loam + poor nutrition
₋ Wind erosion : common problem
 Soil Working :
₋ Trench-cum-pit type : This technique is being extensively used in gently sloping
areas with stony surface. It involves of digging of Staggered contour trenches
spaced 10m x 10m, each being 4.3 m long, 0.60 m wide at the bottom and one
metre wide at the top. In the interspaces, pits of 60 cm long, 60 cm wide and 100
cm deep spaced at 2m x 2m are dug. Both trenches and pits are filled up flush to the
ground with a 50 : 50 mixture of dug up soil and fine textures silt transported from
nearby nala beds.
₋ Irrigation-cum-drainage type : This type of soil working is being largely practised in
low lying areas, namely, river banks and marshy lands with high salt concentration.
In order to facilitate leaching of salts from the root zone, planting is done in 45cm -
50cm deep crow bar holes. Around the plant, 45 cm high mounds are made by
filling the excavated soil from two irrigation-cum-drainage ditches. Each ditch is 100
cm wide on the top 60 cm wide at the bottom and 45 cm deep, and is placed 12.5
cm apart on either side of the planted row. The depth and the width of ditches are
regularly maintained and excess water is drained off from these ditches into
permanent depression or through an artificial channel
 SUITABLE SPECIES :
₋ Sloppy area besides of river banks : Salix alba, S. fragilis, Populus alba and P. ciliata
are successful.
₋ Marshy areas with pH upto 9.5 : Pure Salix plantations

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 2012 : Specific problem of coastal land and Hot deseart (5m)

20.5 | COASTAL LAND

 DISTRIBUTION :
 LOCALITY FACTORS :
₋ Temperature
₋ Rainfall
₋ Soil
₋
 Soil Working :
 Suitable Spp. :

EXERCISE

 2013 : What are the specific problem of the following wasteland ? suggest at least 3 species for
planting in each of them (5m).
₋ Hot deseart
₋ Saline alkaline soil
₋ Wetland
₋ Cold desert
 2012 : Discuss afforestation of inland sand dunes by giving their distribution, site condition,
planting technique and species suitable in each area (5 m)
 2012 : Discus brifly the afforestation technique adopted for ravines land of Yamuna giving
suitabl examples (5m).
 2012 : What are the major ecological consideration in Afforestation (5 m).

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EXERCISE

 2018 : Explain different kinds of thinning and its application in forest ( 8m).
 2017 : Name the method of thinning that best promotes genetic improvement of the
regular stand besides controlling density. Give reasons in support of your answer.
 2016 : Describe important objectives ofthinning. Differentiating crown thinning from
ordinary thinning. Write grades of ordinary thinning ( 8m).
 2014 : Explain the following – ELITE thinning are often difficult to execute (5).
 2013 : Explain the role of thinning in forestry. What are the different methods of
thinning followed in regular crops? Discuss in detail crown thinning. (20 m)

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