Conservation Reader

by Harold W. Fairbanks

When a fire occurs in the dense forests of the Cascade Range, all the trees are killed and the thick layer of decaying vegetation underneath is burned. The spruce, which is one of the most important lumber trees of this region, does not at once spring up again. Its seeds may be scattered there, but the soil is not now in a condition to nourish them. In its place springs up the tamarack pine, which, because it can grow in poor soil, has the whole burned area to itself.

If we should return to the same place perhaps one hundred years after the fire, we should find that the tamarack pines had formed a thick forest. The lumbermen have little use for the tamarack and so have passed it by. In looking carefully through the tamarack forest, we find that other trees are now springing up. They are already struggling for the food, the moisture, and the sunlight which the tamaracks are making use of.

During the many years that have passed since the fire swept this region, decaying vegetation has been slowly accumulating and forming humus again. Now at last the seeds of the spruce find the soil rich enough again to sprout and grow. Here and there are thrifty young trees which will in a few years grow up and choke out the tamarack. Thus the tamarack, though of so little value itself, has done a great work in preparing the soil for a new growth of the valuable spruce.

Upon the drier slopes of the Western mountains shrubs, such as the manzanita and chaparral, spring up and cover the surface after a forest fire. Nature does not seem to want the surface left bare and usually has something at hand, even though it be nothing better than brush, with which to clothe it again. As the years pass humus begins to collect upon the ground and finally restores it to much the same condition it had before the fire. Now, if by any means seeds can reach such places, scattering trees will first spring up in favored spots and, after a time, the trees will become thick enough and large enough to shade the ground and the brush will be killed out.

The cutting of the forests, especially from the steeper mountain slopes, has in many parts of the world changed water, one of Nature's most valuable gifts, into an agent of destruction. Throughout the Eastern and Southern states the floods are higher in spring and lower in summer than they used to be, because of the removal of so large a part of the forests that once covered this whole region.

In the West it is even more necessary that the forest cover be disturbed as little as possible. One reason is that the greater part of the forests are found upon the lofty mountains in which the streams rise. If we deforest these steep slopes, water is going to injure them much more than it would the gentler slopes of the lower lands, if they had been deforested. Another reason is that since little rain falls in the summer in this region, we must do nothing to lessen the summer flow of the streams, which is so much needed for irrigation.

American Forestry Association

This beautiful valley in the Southern Appalachian Mountains has been ruined by the floods due to cutting off of the forests upon the headwaters of the river.

The more water that can be held back in the mountains of the West for summer use, the more prosperous the farmers are. There is nothing that helps to hold the water better than the forests. They help to equalize the flow of the streams so that the floods are not so high in the spring nor the water so low in the summer as they would be if there were no forests.