s of the Trees Have Met. The trees are fifteen years old and in
many cases every other tree had to be removed.]

Forestry, therefore, deals with a vast and varied mass of information,
comprising all the known facts relating to the life of a forest. It does
not deal with the individual tree and its planting and care,--that would
be arboriculture. Nor does it consider the grouping of trees for
aesthetic effect,--that would be landscape gardening. It concerns itself
with the forest as a community of trees and with the utilization of the
forest on an economic basis.

Each one of these activities in Forestry is a study in itself and
involves considerable detail, of which the reader may obtain a general
knowledge in the following pages. For a more complete discussion, the
reader is referred to any of the standard books on Forestry.

The life and nature of a forest: When we think of a forest we are apt to
think of a large number of individual trees having no special
relationship to each other. Closer observation, however, will reveal
that the forest consists of a distinct group of trees, sufficiently
dense to form an unbroken canopy of tops, and that, where trees grow
so closely together, they become very interdependent. It is this
interdependence that makes the forest different from a mere group of
trees in a park or on a lawn. In this composite character, the
forest enriches its own soil from year to year, changes the climate
within its own bounds, controls the streams along its borders and
supports a multitude of animals and plants peculiar to itself. This
communal relationship in the life history of the forest furnishes a
most interesting story of struggle and mutual aid. Different trees
have different requirements with regard to water, food and light.
Some need more water and food than others, some will not endure much
shade, and others will grow in the deepest shade. In the open, a
tree, if once established, can meet its needs quite readily and,
though it has to ward off a number of enemies, insects, disease and
windstorm--its struggle for existence is comparatively easy. In the
forest, the conditions are different. Here, the tree-enemies have to
be battled with, just as in the open, and in addition, instead of
there being only a few trees on a plot of ground, there are
thousands growing on the same area, all demanding the same thing