Value of Legumes
Alfalfa is a legume or nitrogen gathering plant. An examination of the roots of leguminous plants reveals numerous bacteria nodules which vary in size, shape and number according to the kind and age of the plant. A very close relation has been found to exist between leguminous plants and the bacteria existing within these nodules. The plant furnishes the nourishment required by the bacteria while the bacteria in turn draw nitrogen from the air and render it available for the use of the plant. Nitrogen is essential to plant life. The plowing under and resulting decay of legume plants releases vast quantities of nitrogen into the soil where it may be absorbed and assimilated by succeeding crops.
The accompanying [illustration] shows the nodule development on the roots of a two-months-old legume plant.