442 A TEXTBOOK OF GENERAL BOTANY 
allows time for the development of the fruit and at the same 
time facilitates pollination, as both wind and insects have freer 
access to the flowers in a leafless forest than in one in full foliage. 
One of the most striking characteristics of the forests is the 
behavior of small perennial herbs with persistent underground 
portions which send up 
flowers and leaves be- 
fore the appearance of 
the leaves on the trees 
and so make use of 
the bright light which 
reaches them before 
they are shaded by the 
fohage of the trees. 
The aérial parts of 
many of these plants 
disappear early in the 
season. 
The changes in ap- 
pearance which the for- 
ests undergo with the 
changing seasons are 
very striking. During 
the winter the trees are 
leafless and only a por- 
tion of the herbaceous 
vegetation retains its 


Fic. 496. Leafless condition of a deciduous 
forest in the northeastern part of the United : 
States _ early flowering herbs 
carpet the ground and 
flower profusely, while shrubs and trees burst into bloom. 
Most of the trees are wind-pollinated and have inconspicuous 
flowers, but some of them have conspicuous insect-pollinated 
flowers. At this time the great array of blossoms renders the 
forest an object of great beauty. In summer the foliage pre- 
dominates and flowers are scarce. In autumn, before the trees 
foliage. In the spring 
