It is important, then, that we understand why trees grow in some places and not in others, in order that we may know how to take care of them.
CHAPTER SIXTEEN
WHAT ARE THE ENEMIES OF THE TREES?
Every living thing is engaged in a struggle for air to breathe and for something to eat. Those that make their homes on the land also have to struggle for water. The stronger rob the weaker; for, among all of them except man, might always makes right. Men are learning that unselfishness is the better way, although they do not always practice it.
In this struggle the animals have an advantage over the plants, for if food fails in one place they can move to another. Among the animals also the mother tries to protect her children; and, in the case of some,—the wolf, for example,—a number will hunt together for the common good.
It is quite different with the plants. They must grow where the seeds take root. If there is little sunlight or water or the soil is poor, they must make the best of what they have.
The plants have to struggle not only with such enemies as insects, winds, fire, and browsing animals, but with each other, for every tree is the real or possible enemy of every other tree. Brother seeds sprouting under the same parent maple struggle with each other for the food and moisture in the soil and for the best place in the sunlight. The one that gets the most of these will grow the faster and choke some of its weaker brothers.
