Types of Soil Structures

Soil structure is the shape a soil takes according to its physical as well as its chemical properties. Soil is constructed of secondary components called aggregates or peds. Soil aggregates are determined by their shape, size and distinctness. Abiotic processes such as wetting and drying or freezing and thawing develop soil structure, while biotic processes such as compression by roots, burrowing by earthworms, and fungal hyphae develop the soil structure over time, according to scientists at the University of British Columbia.

Granular

Granular soil appears as small pieces of rock or dirt, like pieces of cookie crumbs according to the Soil Science Education website, run by NASA. The crumbs of soil are less than 0.2 inch in diameter and are often found on the surface horizon, or surface layer, of soil. Granular is susceptible to quick change due to weather conditions and human activity.

Block

Block soil type is made up of rocks between 0.6 inch and 2 inches in diameter. Blocky conditions are often found in the A or B horizons of the soil layers and are more often found in regions that are, or once were, humid, according to the University of British Columbia.

Prismatic

Prismatic soil is made up of vertical columns of soil. It is usually found in the lower horizons and is found in arid regions.

Columnar

Columnar soil structures have the same appearance as prismatic soil, appearing in vertical columns, but they have a cap of salt at the end.

Platy

Platy soils are thin, looking like stacked plates when viewed from the side. This type of soil structure is usually found in compacted soil regions.

Single Grained

Single grained is soil that is broken into small particles that do not stick together and has a loose consistency. It is easily poured from the hand. This is commonly found in sandy soils, in the top horizons.

Massive

Massive is a soil type that has no visible particles and no visible structure. It is difficult to break down into smaller pieces and is usually found as large, unworkable clods.

Keywords: soil structures, soil types, soil composition

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Cleveland Van Cecil is a freelancer writer specializing in technology. He has been a freelance writer for three years and has published extensively on eHow.com, writing articles on subjects as diverse as boat motors and hydroponic gardening. Van Cecil has a Bachelor of Arts in liberal arts from Baldwin-Wallace College.