Search results
Results from the WOW.Com Content Network
Atterberg limits. The Atterberg limits are a basic measure of the critical water contents of a fine-grained soil: its shrinkage limit, plastic limit, and liquid limit. Depending on its water content, soil may appear in one of four states: solid, semi-solid, plastic and liquid. In each state, the consistency and behavior of soil are different ...
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. Also, representative soils have been selected for Puerto ...
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 ...
Topsoil is composed of mineral particles and organic matter and usually extends to a depth of 5-10 inches (13–25 cm). Together these make a substrate capable of holding water and air which encourages biological activity. There are generally a high concentration of roots in topsoil since this is where plants obtain most of their vital nutrients.
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 ...
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 typical Natchez soil profile consists of a 3-inch (7.6 cm) top soil of dark grayish brown silt loam and to 8 inches (20 cm), a subsurface of brown silt loam, a yellowish brown and dark yellowish brown silt loam subsoil to 36 inches (91 cm) and a substratum that is yellowish brown, and dark yellowish brown silt loam down to 80 inches (200 cm).
The Storie index is a method of soil rating based on soil characteristics that govern the land's potential use and productivity capacity.Developed by R. Earl Storie at University of California, Berkeley in the 1930s as a method of land valuation, it is independent of other physical or economic factors that might determine the desirability of growing certain plants in a given location.