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This is a list of U.S. state soils. A state soil is a soil that has special significance to a particular state. Each state in the United States has selected a state soil, twenty of which have been legislatively established. These official state soils share the same level of distinction as official state flowers and birds.
The use of soil tests, coupled with the corresponding provisions, can alleviate issues of nutrition and irrigation that can result from non porous Ultisol. [4] Soil tests help indicate the pH, and red clay soil typically has a low pH. [5] The addition of lime is used to help to increase the pH in soil and can help increase the pH in Ultisol as ...
The Unified Soil Classification System ( USCS) is a soil classification system used in engineering and geology to describe the texture and grain size of a soil. The classification system can be applied to most unconsolidated materials, and is represented by a two-letter symbol. Each letter is described below (with the exception of Pt ): If the ...
A Quaternary clay deposit in Estonia, laid down about 400,000 years ago. Clay is a type of fine-grained natural soil material containing clay minerals [ 1] (hydrous aluminium phyllosilicates, e.g. kaolinite, Al 2 Si 2 O 5 ( OH) 4 ). Most pure clay minerals are white or light-coloured, but natural clays show a variety of colours from impurities ...
Alfisol. Alfisols are a soil order in USDA soil taxonomy. Alfisols form in semi-arid to humid areas, typically under a hardwood forest cover. They have a clay-enriched subsoil and relatively high native fertility. "Alf" refers to aluminium (Al) and iron (Fe). Because of their productivity and abundance, Alfisols represent one of the more ...
Soil types by clay, silt and sand composition as used by the United States Department of Agriculture. Loam (in geology and soil science) is soil composed mostly of sand (particle size > 63 micrometres (0.0025 in)), silt (particle size > 2 micrometres (7.9 × 10 −5 in)), and a smaller amount of clay (particle size < 2 micrometres (7.9 × 10 −5 in)).
The AASHTO Soil Classification System was developed by the American Association of State Highway and Transportation Officials, and is used as a guide for the classification of soils and soil-aggregate mixtures for highway construction purposes. The classification system was first developed by Hogentogler and Terzaghi in 1929, [ 1] but has been ...
A taxonomy is an arrangement in a systematic manner; the USDA soil taxonomy has six levels of classification. They are, from most general to specific: order, suborder, great group, subgroup, family and series. Soil properties that can be measured quantitatively are used in this classification system – they include: depth, moisture ...