(introduction...)

The use of organic fertilizers is another method of correcting soil nutrient deficiencies. Although it is more labor intensive than chemical fertilization, it has the advantages of being locally produced; maintaining soil humidity; improving soil organic matter content, structure and texture; adding a better balance of micronutrients, and improving the soils capacity to hold nutrients. Organic fertilizer refers to a number of types of organic matter which can be incorporated into soils or left as a mulch on the surface. This may be as simple as incorporating crop residues or manure, or as complex as planting a green manure crop, making compost, or raising earthworms to produce materials which will be incorporated into the soil at some later date.

A traditional practice in many areas is the burning of residues left when initially clearing land or after a harvest. Although some nutrients are returned to the soil in the ashes, much of the organic matter and nitrogen present are lost to the air. m is loss of organic matter affects all of the just mentioned soil properties.