White sweet clover (fig. 2) is ordinarily referred to as melilotus
or meliot in the South and merely as sweet clover in other portions
of the country. When soil conditions are favorable for germination,
sweet-clover seedlings will appear from one to two weeks after seeding.
On account of the biennial nature of the plants, they do not seem
to make much growth above ground the first month or six weeks after
germination, but during this time they are developing root systems
rapidly and thus becoming established, so to be able to withstand
adverse conditions. Plants which have made no more than 2 inches of top
growth very often have produced roots 6 inches or more in length (fig.
3). The tap-root continues to develop rapidly throughout the growing
season the first year, and by autumn often reaches a length of 24 to 36
inches and a diameter of three-fourths to 1 inch at the crown.
[Illustration: Fig. 2.--A branch of white sweet clover, showing the
long, loose racemes which bear white flowers.]
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.
[Illustration: 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.