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 WHICH SHALL IT BE?

 WHAT WE OWE TREES.

Did you ever stop to think how much we owe to trees? Let us see.

You have learned in school that trees purify the air by taking out of it gases which are hurtful to man, and also that they purify the springs of water at their roots; consequently, you understand why it is that terrible fevers have so often followed the cutting down of forests in a new country. But do you know, too, that the health-giving quality of trees is only one of their many virtues? Not the least of these is the prevention of floods, and the droughts which follow floods. You will wonder how this is. Now you know if you hang out a piece of wet cloth in the sun and wind it will become quickly dry. The water in it has evaporated. So it is with the open spaces where there are no trees. And the moisture, which has all at once been absorbed by the air, is discharged in torrents instead of in gentle rains, as would be the case if there were trees and and it was absorbed gradually. Here again comes in the question of health, for floods and droughts are as hurtful to man as the soil which suffers from them.

A way in which trees help us greatly, which is not often thought of, is by preventing so great extremes of heat and cold as there would otherwise be. Your geographies tell you how the ocean equalizes the climate of places upon it. It is upon the same principle that trees modify climate, though in a lesser degree.

Their effect upon desert land should be spoken of as well. It has been found that, where trees have been planted to keep off the winds of the ocean from such land, in a short time crops could be raised. This is because the winds take up moisture very quickly. When they cease to blow, therefore, or blow less hard, the rainfall is increased. Indeed, it has been thought that even the terrible Sahara desert itself, might be made fertile by planting trees. It is known that springs of water in the oases disappear if the trees are for any reason destroyed, and also that new springs appear in the spots where they have been made to grow.

None, perhaps, can appreciate so fully their loveliness and charm as those who have crossed the desert plains of the great West. How the passengers on the overland train crowd about the little plats of grass (carefully guarded by iron fences), where trees are growing, while such exclamations as "O, don't they look good?"