Topsoil and subsoil | Physical properties of soil | Principles of Horticulture | Botany

Topsoil and subsoil

Content

⇒	Physical properties of soil
	⇒	Plant requirements
	⇒	Composition of soil
	⇒	Formation of soils
	⇒	Natural soil profiles
	⇒	Soils of the British Isles
	⇒	Topsoil and subsoil
	⇒	Soil components
	⇒	Soil texture
	⇒	Soil structure
	⇒	Cultivations
	⇒	Management of main soil types

In natural conditions organic matter is more abundant at the surface and declines in concentration with depth, whereas under cultivation the organic matter is redistributed to create a distinct topsoil and subsoil with the boundary at ‘plough depth’. The dark colour that the decomposed organic matter gives the soil makes the boundary obvious by the colour change.