Brown Forest Soils

soils formed under mixed broad-leaved or, less frequently, coniferous forests under conditions of a temperate, warm, moist climate on soil-forming rocks of various origin and mechanical composition. The soils are usually distinguished by their brown color and lumpy, nutty texture. In cross section, brown forest soils are divided into A₀, a layer of forest litter 2-5 cm thick; A₁, a humus layer 15-20 cm thick (occasionally up to 30 cm thick); and B, the lower layer of maximum loam (15-40 cm thick). The greatest quantity of humus (6-10 percent) is contained in the humus layer. The acidity and degree of saturation with bases of brown forest soils depend on their geographic position; a more acidic reaction of such soils is found in southern regions. Brown forest soils are further subdivided into typical (saturated or unsaturated with bases and residually carbonaceous), podzolized, and gley (surface gley or pseudopodzolic) soils. Brown forest soils are found in western and central Europe, in the northwestern USA, in China, and in Korea. In the USSR they are found in the Carpathians, the Crimea, the Caucasus, and the southern part of the Far East. High yields of tobacco, grapes, tea, and other crops can be grown on brown forest soils, which also have great value for forestry.