Fig. 247. Three clovers, respectively, Buffalo, Yellow, and Rabbit-foot clover.
The White Clover. (T. repens.)—This beautiful little clover, whose leaves make a rug for our feet in every possible place, is well known to us all. It is the clover best beloved by honey-bees, and the person who does not know the distinct flavor of white clover honey has lost something out of life. While in hard soil the white clover lasts only two or three years, on rich, moist lands it is a true perennial. While it was probably a native in the northern part of America, yet it is truly cosmopolitan and may be found in almost all regions of the temperate zones. Very likely the common stock of it is an introduction from Europe. By many this is considered to be the original shamrock.
The Yellow, or Hop Clover ([Fig. 247]). (T. agrarium.)—This friendly little plant, filling waste places with brilliant green leaves and small yellow flower-heads, is not considered a clover by those who are not observant. But if the flowerets in the small, dense heads are examined, they will be seen to resemble very closely those of the other clovers. The stems are many-branched and often grow a foot or more in height. The flowers are numerous, and on fading turn brown, and resemble the fruit of a pigmy hop vine, whence the name. Its leaves are much more pointed than those of the medics, with which it might be confused because of its yellow flowers.
Low Hop Clover, or Hop Trefoil. (T. procumbens.)—This resembles the above species, except that it is smaller and also more spreading, and the stems and leaves are more downy.
The Least Hop Clover. (T. dubium.)—This may be readily distinguished from the above species by the fact that its yellow flowerets occur from three to ten in a head. This is said by some to be the true shamrock, although the white clover is also called the shamrock.
The Rabbit-Foot, or Stone Clover ([Fig. 247]). (T. arvense.)—This is another clover not easily recognized as such. It grows a foot or more in height and has erect branches. The leaflets are narrow and all arise from the same point. The flowerets occur in long, dense heads. The calyx is very silky, and the lobes are longer than the white corollas, thus giving the flower-head a soft, hairy look, something like the early stages of the blossom of the pussy willow. Because of its appearance it is often called "pussy clover."
The Medics. (Medicago.)
Alfalfa ([Fig. 248]). (Medicago sativa.)—This is the veteran of all the clovers, for it has been under cultivation for twenty centuries. It is a native of the valleys of western Asia. In America it was first introduced into Mexico with the Spanish invasion. It was brought from Chile to California in 1854, where it has since been the most important hay crop. In fact, there is no better hay than that made from alfalfa. It was probably introduced into the Atlantic States from southern Europe, and has grown as a weed for many years in certain localities in New England and the Middle States; only recently has it been considered a practicable crop for this climate, although it was grown in Jefferson Co., N. Y., in 1791. Its special value is that it is a true perennial, and may be cut three times or more during a season, and when once established it withstands hot, dry weather. It is of marvelous value to the semi-arid regions. The alfalfa flower is blue or violet, and grows in a loose raceme. The plant grows tall and its stems are many branched. This and all these medics are introduced from Europe.
Fig. 248. Alfalfa, foliage and flowers.