water clover, common name for various species of aquatic ferns.

sweet clover or melilot, Eurasian and North African leguminous herbs of the genus Melilotus of the family Leguminosae (pulse family). Sweet clovers, now widely naturalized in North America, are used as forage, cover, and soiling crops. Attractive to bees for their fragrant blossoms, they are also honey plants. Melilotus is a different genus from that of the true clovers. Sweet clover is classified in the division Magnoliophyta, class Magnoliopsida, order Rosales, family Leguminosae.

clover, any plant of the genus Trifolium, leguminous hay and forage plants of the family Leguminosae (pulse family). Most of the species are native to north temperate or subtropical regions, and all the American cultivated forms have been introduced from Europe. Red clover (T. pratense), the state flower of Vermont, was the leading leguminous hay crop of the northeastern regions until it was surpassed by alfalfa. It is frequently seeded with timothy. Swedish, or alsike, clover (T. hybridum) is similarly used in the same area. The common white, or Dutch, clover (T. repens) is also cultivated at times but is considered a weed in fields and pastures, where it spreads rapidly. Its dried flower and seed heads were used for making bread during famines in Ireland and the leaves are eaten as salad in some parts of the United States. The clovers are excellent honey plants. Other plants are sometimes called clover, e.g., the related melilot, or sweet clover. Clover was used by the Greeks in garlands and other decorations. The druids held it sacred. It is said to have been the early emblem of Ireland from which the shamrock is derived, and it is an emblem of the Trinity. English and American poets have celebrated it. A four-leaved clover is thought to bring good luck. See also lespedeza; trefoil. Clover is classified in the division Magnoliophyta, class Magnoliopsida, order Rosales, family Leguminosae.

buffalo clover: see lupine.

Any legume of the genus Trifolium, composed of 300 or more annual and perennial species, found in most temperate and subtropical regions. The alternate, compound leaves usually have three toothed leaflets. The very small, fragrant flowers are crowded into dense heads. Clovers are highly palatable to livestock and high in protein, phosphorus, and calcium, thus providing valuable nourishment in the form of hay, pasture, and silage. They also improve and conserve soil by adding nitrogen and increasing the availability of other nutrients for crops that follow. The most important agricultural species are red clover (T. pratense), white clover (T. repens), and alsike clover (T. hybridum).

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