The speed of soil destruction, with its erosion after plowing, is particularly noticeable with the great American crops, cotton, corn and tobacco, which require clean cultivation. Many orchards are also cultivated for the double purpose of keeping down rival plants and preserving moisture, but we pay high in soil loss for the moisture that we get by that means on hilly lands. The plow is one of the greatest enemies of the future. As a matter of fact we have already destroyed enough land in the United States to support many millions of people; and therefore the tree is the more important because it permits an agriculture that will keep the soil indefinitely, and in permanent production, without plowing. I have aecidently discovered a better way of conserving moisture than by plowing, and I have found it going on in widely scattered places and in widely different climates. Primitive peoples in many parts of the world have long since obtained the advantage of cultivation, mainly, increasing the available moisture for the tree or plant, without cultivation of the soil and the loss which follows the washing of cultivated soils. As an example I cite the Indians of Arizona, who have grown corn crops for centuries in a country with but from six to fifteen inches of rain. They do this by planting in little patches at the mouth of a gully where at the time of rain the flood water is led away into furrows and depressions so that it thoroughly soaks the ground in which the corn is planted. My attention was first called to this practice by observing a good patch of barley in the edge of the Sahara in Southern Tunis, where the gulley flow resulting from a winter rain had spread itself out fan-*like and soaked the triangular alluvial area of sand, which bore a fine crop of barley in the midst of the desert. For centuries the olive growers of parts of Tunis have led gulley water to the olive trees where it was retained, in areas that resembled a tennis court, with a 12 inch bank of dirt around it and two or three olive trees within this area thus watered by impounding. A practice somewhat similar to this is shown in F. H. King's classic book on Chinese agriculture, "Farmers of Forty Centuries;" but the most extreme case that has come to my attention is furnished by the Berber tribe of the Matmatas, of Tunis. These people live on the edge of a hilly, limestone plateau, where the rainfall is less than 10 inches and in some years as low as five.