Classification

There are many ways of classifying soil. The major ones include:

Classification based on colour

Classification based on particle sizes

Classification based on climatic region

Classification of soil based on colour

Red clay soils: They are found on the northern and N. western parts of l. Victoria. These are deep, have stable structure and fairly high water holding capacity.

Brown soils: Mainly found in western and south western Uganda. They are shallow but fertile.

Reddish sandy soil: occupy large areas of central Uganda. Are acidic and of fairly low fertility.

Yellowish sandy soils: wide spread in eastern and northern Uganda. They are shallow, free draining, low in fertility and underlaid by murram.

Classification based on particle size

Soil separatesDiameter (mm)
GravelAbove 2.0
Coarse sand2.0 – 0.2
Fine sand0.2- 0.02
Silt0.02 – 0.002
ClayBelow 0.002

These are further divided into sub-classes due to the %age of particle sizes present in each i.e.

Silt loam has 20- 39%sand, 70% silt, 10%  clay , 0.004% om.

Clay loam has 20- 60% silt, 20- 30% clay, 20- 60% sand, 0.1- 0.6% om

Sandy loam has 20 – 50%, silt clay 50- 80% sand, 0.13% om.

Loam soil has 45%sand, 40% silt, 25% clay, 1-4% om.

Classification based on climatic region

Zonal soils: are characterized and influenced by climate and world vegetation.

Intrazonal soils: are characterized and influenced by local conditions e.g. drainage, pH, mineral content etc.

Azonal soils: Have characterized by parent rocks of origin.