Soil Consistence
Soil consistence refers to the resistance of soil to mechanical stresses or manipulation. It reflects both:
- Cohesion: Force between similar particles (e.g., soil particles).
- Adhesion: Force between dissimilar substances (e.g., soil and water).
Soil consistence varies with moisture content and is evaluated at three moisture levels:
- Wet Soil (Stickiness & Plasticity)
- Moist Soil (Crushability)
- Dry Soil (Hardness)
Wet Soil Consistence:
Wet soil properties are assessed based on stickiness and plasticity.
a. Stickiness: (Feel test between thumb & forefinger)
- Non-sticky: No soil sticks to fingers.
- Slightly sticky: Slight sticking; separates cleanly without stretching.
- Sticky: Sticks to both fingers; stretches slightly before breaking.
- Very sticky: Firmly sticks and stretches significantly when fingers are pulled apart.
b. Plasticity: (Wire formation test)
- Non-plastic: No wire can be formed.
- Slightly plastic: Wire forms but breaks easily & can be reformed.
- Plastic: Wire forms but breaks and can’t be reformed easily.
- Very plastic: Strong wire forms; difficult to break; can be reformed multiple times.