LEGUMINOUS PLANTS. 13
deplete the soil, and the same is true, in a general way, of other grasses. Leguminous plants (see page 18) accumulate nitrogen from the air and are of great importance as soil improvers. Clovers return nitrogen to the soil, and thus to a certain degree maintain its fertility.
Name: These plants belong to a large family of a distinct type, called Leguminosw. Peas, Vetches, Beans, Red Clover, Alsike and Alfalfa belong to this great family—that is, the plants which farmers commonly term legumes and clovers. As generally used, the name
clovers " includes Red Clover, Alsike, Dutch Clover, Crimson Clover, Alfalfa, Trefoil, Sweet Clover and other leguminous plants. Botanically, however, only the first four are clovers in the true sense; that is, they belong to the genus Trifolium, whereas Alfalfa, Trefoil and Sweet Clover belong to other genera.
Seed: When splitting a bean or a pea, the two halves seem
to be kept together by the seedcoat only. One of them has a