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UNDERSTORY PLANTS
The understory of a forest is composed of trees, shrubs,
and ground plants. The trees are either seedlings
struggling to survive or are older trees
that have been suppressed by the lack of sunlight.
This section will address the other plants - the shrubs
and ground plants.
The development of understory growth is dependent upon
several factors: the quality of the soil, the amount of
rain, and especially the density of the
canopy. Oak forests usually have a thicker understory
than a beech-maple forest because oak canopies are more
open and oak crowns are not as dense as maple crowns or
beech crowns. Canopy density appears to control what
grows on the forest floor.
There are different ways that plants have adapted to
live within the forest, competing for sunlight and
nutrients.
Some try to complete all of their annual growth before
the canopy closes over with leaves; they grow in the
spring or fall. Examples are bloodroot and may
apple.
Some have adapted to live with very little or no direct
sunlight; examples of these would be the lichens and
mosses.
Some plants start on the forest floor with extensive
root systems and send up shoots that reach the forest
canopy; these are the vines. Both virginia creeper
(vine) and grape vines can overtop trees and shade the
canopy. Grape vines will deprive trees of enough
sunlight that they will die.
Some plants grow in clusters, shading out any
competitors - claiming a small section of forest floor
and resources. Examples include dogwood and prickly
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