soil

Soil, superficial covering of most of the earth’s land area; an aggregation of unconsolidated mineral and organic particles produced by the combined action of wind, water, and organic decay. Soils vary widely from place to place. The chemical composition and physical structure of the soil at any given location are determined by the kind of geologic material from which it originates, by the vegetation cover, by the length of time that the soil has …showed first 75 words of 824 total…

…showed last 75 words of 824 total…not an index of fertility. Soils having a red or reddish-brown hue usually contain a large proportion of iron oxides (derived from the parent rocks) that have not been subjected to excessive humidity. Red color in a soil, therefore, is generally an indication that the soil is well drained, not excessively humid, and fertile. This generalization is particularly true in the southeastern U.S. but is not always true in other parts of the wor