ABSTRACT
Green manuring is the tilling of green, growing plants into the ground to improve the condition of the soil. Increasing the organic matter content of soil is the primary purpose of green manuring. For maximum benefits, the green manure crop should be in a crop rotation every third year, such as a rotation of corn-oats-green manure or vegetable-vegetable-green manure. Nitrogen is added to the soil by nitrogen fixation if the green manure crop is a legume. Nitrogen fixation is a process by which nitrogen in the air is converted into ammonium nitrogen. Nonlegumes that are grown as green manures do not add nitrogen to the soil, for they do not have capacity to fix nitrogen. Nonlegumes, however, or legumes will help to conserve nutrients. The roots of these crops will intercept nutrients that might otherwise be lost by leaching. These green manures are called catch crops. Cover crops should be used on sloping land to protect it against soil erosion.
