Soil Consistency

Soil Consistency the feel of the soil, reflecting relative resistance to pressure: eg friable, firm, hard, loose, plastic. The term soil consistency is used to describe the resistance of a soil at various moisture contents to mechanical stresses or manipulations. It is commonly measured by feeling and manipulating the soil by hand or by pulling a tillage instrument through it. The consistency of soils is generally described at three soil moisture levels: wet, moist and dry. Terms used to describe soil consistency at these three moisture levels are shown in the table.

Wet soils Moist soils Dry soils
Stickiness Plasticity Nonsticky
Nonplastic Loose Loose
Slightly sticky Slightly plastic Very friable
Soft Sticky Plastic
Friable Slightly hard Very sticky
Very plastic Firm Hard Very firm
Very hard Extremely firm Extremely hard

Terms such as weakly cemented, strongly cemented, and indurated are used to define categories of cementation. Consistency has importance for the practical use of soils such as soil tillage and compaction by farm machinery.

acid basin clays are featured by heavy soil consistency (making the soils difficult to plough both when wet and when dry). Noncalcareous Grey Floodplain soils and Noncalcareous Dark Grey Floodplain soils show firmer consistency. Calcareous Brown Floodplain soils develop more friable consistency. [Md Mizanur Rahman Bhuiyan]