Clovers have flowers in mostly dense, rounded clusters. Sometimes the flower clusters have involucral bracts at the base. The colors are white, yellow, or pink to red or purple. The calyx is persistent, 5-toothed. The corolla has the banner usually only slightly reflexed from the wings and keel. The fruit is a legume, round to elongated, usually shorter than, and included within the calyx, not splitting, with 1 to several rounded seeds. The plants of the genus Trifolium are annual or perennial, taprooted or rhizomatous herbs, with leaves that are usually palmately to semi-pinnately divided into 3 leaflets, rarely palmately into 4 to 9 leaflets. The leaflets are entire or shallowly toothed. The stipules are membranous to leafy, and often joined. There are nearly 300 species of clovers worldwide, mostly of the N. Temperate Zone, especially in Western N. America, less abundant in S. America and Africa. The word Trifolium means three leaflets on each leaf. Although there are many species, only about ten are significant as forages. Many are trailing in growth or weak stemmed which makes them persistent to grazing. The common trifoliums used as forage are: white, red, crimson, subterraneum, alsike, and berseem clover. Many species of the genus Trifolium flourish in wide varieties of habitats ranging form sub-Arctic regions to tropical regions of Africa and South America. Trifolium is fertilized through pollination by insects such as the honeybees and bumblebees. Clover plays an important role in pasture lands through its nourishment to animals and beneficiary effects on grass when winter kills and summer droughts occur. However, evidence has shown that some clovers can cause poisoning to livestock. In addition, some clovers have medicinal purposes in the areas of blood purification and relief from inflammation and coughing.
Guide to Identify Presented Species of Genus Trifolium
FLOWERS MOSTLY PINK OR PURPLISH PLANTS AT LEAST 10 CM TALL
T. pratense – Red Clover Widely branched perennial, 20-60 cm tall. Disturbed or cultivated ground.
Flowers deep red to pink, 13-20 mm long, in dense, round heads 2-3 cm wide.
Leaves with 3 egg-shaped leaflets, the uppermost 2 just below the flower head.
FLOWERS MOSTLY WHITE OR WITH SOME PURPLE
T. repens – White Clover Mat-forming, stems short, rooting at nodes. Disturbed ground, meadows, lawns.
Flowers 5-9 mm long, in round heads 15-20 mm broad. Calyx hairless.
Leaves with short to long stalks, the 3 leaflets 1-2 cm long, finely toothed.
