Great areas of grazing lands were plowed for the first time and turned into crop lands. Timber cutting became an industry. Thus began the upsetting of Nature's dynamic equilibrium in the soil and forests that is resulting in an annual waste of resources far greater and more serious than most individuals realize. Keystone in the equilibrium were the forests. Besides their effect of binding the soil together with their roots and checking the flow of water and the melting of snow, trees have a tremendous influence on precipitation.
Trees also emit much moisture through their leaves.
And only a small part has been replanted. With the destruction of our forests, water and winds have been free to erode our soil. The destruction of our soil cannot be measured in dollars and cents. Ten billion dollars could not buy back the top soil that has been washed into the ocean, taken out by crops, or blown away. It is irreplaceable.