Soil colour is an important indicator of soil health including mineral composition, soil organic matter, soil fertility, soil moisture, drainage etc as well as the past and present oxidation-reduction conditions of the soil. Soil color is also used to distinguish soil horizons. Soil displays a wide range of colors according to presence of minerals and organic content in it. For example, soil having brown/dark brown/black colour indicate the presence of organic matter, darker is the colour more will be the organic matter; yellow/pale brown indicated presence of iron oxides, poor organic matter and nutrients; white colour indicates presence of calcium and silica, red colour indicates presence of iron. All soil colors display darker under wet condition and lighter in dry condition, therefore determination of soil colour should be done under uniform conditions. Early morning and late evening readings are not accurate. The soil colour is determined by using Munsell colour chart. In his chart different colour chips are systematically arranged by three variables namely Hue, Value and Chroma. Hue indicates the spectral colors like red, yellow, blue, green etc; Value indicates lightness or darkness of the colour on a scale; Chroma indicates the range of strength of colour on a scale. The combination of these three variables is used to describe the colour of a soil.
