ARCHIVE: Fertiliser Manual (RB209)

Description of Soil Types

Soil Category Description of Soil Types Within Category
Light sand soils Soils which are sand, loamy sand or sandy loam to 40 cm depth and are sand or loamy sand between 40 and 80 cm, or over sandstone rock
Shallow soils Soils over impermeable subsoils and those where the parent rock (chalk, limestone or other rock) is within 40 cm of the soil surface. Sandy soils developed over sandstone rock should be regarded as light sand soils.
Medium soils Mostly medium-textured mineral soils that do not fall into any other soil category. This includes sandy loams over clay, deep loams, and silty or clayey topsoils that have sandy or loamy subsoils.
Deep clayey soils Soils with predominantly sandy clay loam, silty clay loam, clay loam, sandy clay, silty clay or clay topsoil overlying clay subsoil to more than 40cm depth. Deep clayey soils normally need artificial field drainage.

Deep silty soils

Soils of sandy silt loam, silt loam or silty clay loam textures to 100 cm depth or more. Silt soils formed on marine alluvium, warp soils (river alluvium) and brickearth soils are in this category. Silty clays of low fertility should be regarded as other mineral soils.
Organic soils Soils that are predominantly mineral but with between 10 and 20% organic matter to depth. These can be distinguished by darker colouring that stains the fingers black or grey.
Peat soils Soils that contain more than 20% organic matter derived from sedge or similar peat material

 Assessment of Soil texture

Accurate measurement of soil texture requires laboratory analysis, but for practical purposes texture can be assessed by hand using the following method:

Take about a dessert spoonful of soil. If dry, wet up gradually, kneading thoroughly between finger and thumb until soil crumbs are broken down. Enough moisture is needed to hold the soil together and to show its maximum stickness. Follow the paths in the diagram to get the texture class.

A texture triangular diagram, defining the particle size distribution for each named texture class, is given in Appendix D of Controlling Soil Erosion (MAFF PB4093).

ADLib logo Content provided by the Agricultural Document Library
© University of Hertfordshire, 2011