Green manure

In agriculture, a green manure is a crop specifically cultivated to be incorporated into the soil while still green. Typically, the green manure's biomass is incorporated with a plow or disk, as is often done with (brown) manure. The primary goal is to add organic matter to the soil for its benefits. Green manuring is often used with legume crops to add nitrogen to the soil for following crops, especially in organic farming, but is also used in conventional farming. Farmers apply green manure by blending available plant discards into the soil. Farmers begin the process of green manuring by growing legumes or collecting tree/shrub clippings. Harvesters gather the green manure crops and mix the plant material into the soil. The un-decomposed plants prepare the ground for cash crops by slowly releasing nutrients like nitrogen into the soil. Farmers may decide to add the green manure into the soil before or after cash crop planting. This variety in planting schedules can be seen in rice farming. Green manures are meant to be used alongside chemical fertilizers as a way to reduce our use of chemical fertilizers. When used alone, we cannot see all the advantages of green manures Green manures usually perform multiple functions that include soil improvement and soil protection: Leguminous green manures such as clover and vetch contain nitrogen-fixing symbiotic bacteria in root nodules that fix atmospheric nitrogen in a form that plants can use. This performs the vital function of fertilization. Depending on the species of cover crop grown, the amount of nitrogen released into the soil lies between 40 and 200 pounds per acre. With green manure use, the amount of nitrogen that is available to the succeeding crop is usually in the range of 40-60% of the total amount of nitrogen that is contained within the green manure crop. {| class="wikitable" |- |+Average biomass and nitrogen yields of several legumes ! Crop ! Biomass (tons acre−1)