In the four European tree species the researchers looked at: horse chestnut, scots pine, alder and ash, the time interval between leaf unfolding and flowering increased at a rate of 0.6 to 1.3 ...

Black alder, which is also known as common alder or European alder, is found in most of Europe and extends into North Africa and Asia. It is easily identified by its gummy twigs and leaves. Learn more ...

The unfolding of a tree's leaves mark the beginning of the year's growth cycles, while flowers signals the start of the reproduction cycle. Between 1950 and 2013, the delay between these two ...