Bulletin Volume 80-87

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1911 Excerpt: ...except texture. Owing to the fact that very nearly similar soil material may be deposited by different agencies there may be a closer resemblance in two series formed from rocks of different origin than between two derived from rock of similar origin. For this and other reasons a classification based upon difference in the soil itself would be more desirable and some time will doubtless be made. 1 Two other divisions might possibly have been added, "alkali" soils, representing an excessive accumulation of soluble salts and semiarld soils or slightly leached surface soils containing considerable humus but having unleached subsoils. As the former cai be so readily changed by leaching out the injurious salts It seems best to consider the "alkali" soils as a variation of the arid, while the semiarld constitute a transition from the Arid to the Dark-colored Prairie soils. It has already been pointed out that texture is the most important physical property of the soil. According to differences in this property the series are divided into classes, or into sand, loam, clay, or some intermediate class. In order to bring out the importance of this property of the soil, the texture is made a part of the type name. There are undoubtedly a large number of soil series, and it is possible in this paper to describe only some of the more representative. In some cases no division of the larger groups into series was attempted. ARID SOILS. The distinguishing characteristics of the Arid soils are (1) a large quantity of soluble mineral matter, (2) low content of organic matter, (3) generally gray or light color, (4) deep soils with little change in character with depth, (5) small quantity of clay, especially in the subsoil, unless formed from clay deposits,...