. Adventures with animals and plants. Biology. PROBLEM 4. Why We Must Practice Conservation. Fig. 354 A hillside tuat has gone tu iiaste. Can you explain how:' (u. s. soil conser- vation service) Overgrazing causes loss of good soil, too. When too many animals graze on too small an area, they are forced to eat all the green parts above the ground, starving the roots which bind the soil. Sheep and goats are particularly destruc- tive because they crop very close to the ground. Stripped of its cover of grass, much of the topsoil is washed and blown away. (See Figs. 354 and 356.) The land becomes
. Adventures with animals and plants. Biology. PROBLEM 4. Why We Must Practice Conservation. Fig. 354 A hillside tuat has gone tu iiaste. Can you explain how:' (u. s. soil conser- vation service) Overgrazing causes loss of good soil, too. When too many animals graze on too small an area, they are forced to eat all the green parts above the ground, starving the roots which bind the soil. Sheep and goats are particularly destruc- tive because they crop very close to the ground. Stripped of its cover of grass, much of the topsoil is washed and blown away. (See Figs. 354 and 356.) The land becomes poorer and poorer. In some sec- tions of our country the topsoil is en- tirely gone. Overgrazing is partially the cause of the treeless slopes of Spain and other Mediterranean countries. Ordinary farming operations cause much loss of topsoil too. In plowing the land we expose the topsoil to the action of rain and wind. Furthermore, unless the farmer adds fertilizers or takes other precautions, the nitrogen and other min- eral compounds will soon be exhausted. Soil conservation. The United States government through several of its bu- reaus, some of the State governments, and groups of private individuals who are concerned about the future welfare of the country have attacked the prob- lem of soil conservation in several ways. Education of farmers and city dwellers in regard to the need for soil conserva- tion and the danger of forest destruction is the first job to be done. Government agencies search for plants which may be used to bind the soil. Research workers devise and try out ways of farming to. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Kroeber, Elsbeth, 1882-; Wolff, Walter Harold, 1901-. Boston : D. C. Heath
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