After the root system becomes established the plants produce an upright, branching, leafy growth, which under ideal growing conditions may reach a height of 48 inches the first season, but more often 18 to 30 inches. A large quantity of reserve food is stored in the tap-root the first season; this reserve food enables the plants to make a rapid and vigorous growth early the following spring.
Fig. 3.—White sweet-clover plants collected from a plat six weeks from the date of seeding. An extensive root system such as is shown here is often developed before much growth is made above ground.
Toward the end of the growing season of the first year a number of buds, which serve to produce the second year's growth ([fig. 4]), are formed on the crowns of the plants. After these buds are formed the plants may be clipped quite close to the ground, as the buds are not developed until the plants have made sufficient growth to live through the winter.
During the second season sweet clover makes a rapid, erect, stemmy, branching growth from 5 to 10 feet in height, the plants producing only a moderate number of leaves, which drop as the seed matures. A large number of loose racemes bearing white flowers (see [fig. 2]) are produced during the flowering period, which usually lasts from three to five weeks.
Before sweet clover has made a growth of 12 to 18 inches it closely resembles alfalfa. The plants may be distinguished from alfalfa by the absence of pubescence on the under side of the leaves and by their bitter taste. When they are in bloom they may be identified easily by their long, loose racemes of white flowers and their open, coarse growth. Unlike alfalfa, the seeds are ordinarily found singly in the pods. Two seeds may occasionally be found, and very rarely three, in a single pod.
Fig. 4.—Buds produced on the crown of a sweet-clover plant at the end of the first season's growth. These buds will produce the first crop the second season.