Clover, also called trefoil, are plants of the genus Trifolium, consisting of about 300 species of flowering plants in the legume family Fabaceae originating in Europe. The genus has a cosmopolitan distribution with highest diversity in the temperate Northern Hemisphere, but many species also occur in South America and Africa, including at high altitudes on mountains in the tropics. They are small annual, biennial, or short-lived perennial herbaceous plants, typically growing up to 30 centimetres (12 in) tall. The leaves are trifoliate, with stipules adnate to the leaf-stalk, and heads or dense spikes of small red, purple, white, or yellow flowers; the small, few-seeded pods are enclosed in the calyx. Other closely related genera often called clovers include Melilotus and Medicago.
Trifolium repens, the white clover, is a herbaceous perennial plant in the bean family Fabaceae. It is native to Europe, including the British Isles, and central Asia and is one of the most widely cultivated types of clover. It has been widely introduced worldwide as a forage crop, and is now also common in most grassy areas of North America, Australia and New Zealand. The species includes varieties often classed as small, intermediate and large, according to height, which reflects petiole length. The term 'white clover' is applied to the species in general, 'Dutch clover' is often applied to intermediate varieties, and 'ladino clover' is applied to large varieties.
Trifolium stoloniferum, the running buffalo clover, is an endangered species of perennial clover native to the eastern and midwestern United States. From 1940 to 1985 it was believed to be extinct until two populations were discovered in West Virginia. Since then, more populations have been found in the US but it still remains one of the most imperiled plants in North America.
Trifolium pratense, red clover, is a herbaceous species of flowering plant in the bean family Fabaceae, native to Europe, Western Asia, and northwest Africa, but planted and naturalized in many other regions.
Trifolium aureum, known by the various common names large hop trefoil, large trefoil, large hop clover, golden clover or hop clover, is a species of flowering plant native to much of Eurasia.
Trifolium arvense, commonly known as the hare's-foot clover, rabbitfoot clover, stone clover or oldfield clover, is a flowering plant in the bean family Fabaceae. This species of clover is native to most of Europe, excluding the Arctic zone, and western Asia, in plain or mid-mountain habitats up to 1,600 metres (5,200 ft) altitude. It grows in dry sandy soils, both acidic and alkaline, soil with dry-mesic conditions and is typically found at the edge of fields, in wastelands, at the side of roads, on sand dunes, and opportunistically in vineyards and orchards when they are not irrigated.
Trifolium subterraneum, the subterranean clover, subterranean trefoil, is a species of clover native to Europe, Southwest Asia, Northwest Africa and Macaronesia. The plant's name comes from its underground seed development (geocarpy), a characteristic not possessed by other clovers.
Trifolium campestre, commonly known as hop trefoil, field clover and low hop clover, is a species of flowering plant native to Europe and western Asia, growing in dry, sandy grassland habitats, fields, woodland margins, roadsides, wastelands and cultivated land. The species name campestre means "of the fields".
Melilotus albus, known as honey clover, white melilot (UK), Bokhara clover (Australia), white sweetclover (US), and sweet clover, is a nitrogen-fixing legume in the family Fabaceae. Melilotus albus is considered a valuable honey plant and source of nectar and is often grown for forage. Its characteristic sweet odor, intensified by drying, is derived from coumarin.
Trifolium incarnatum, known as crimson clover or Italian clover, is a species of herbaceous flowering plant in the family Fabaceae, native to most of Europe. It has been introduced to other areas, including the United States and Japan.
Trifolium wormskioldii is a species of clover native to the western half of North America. Its common names include cows clover, coast clover, sand clover, seaside clover, springbank clover, and Wormskjold's clover.
Trifolium amoenum, known by the common names showy Indian clover and two-fork clover, is endemic to California, and is an endangered annual herb that subsists in grassland areas of the San Francisco Bay Area and the northern California Coast Ranges.
Trifolium hybridum, the alsike clover, is a species of flowering plant in the pea family Fabaceae. The stalked, pale pink or whitish flower head grows from the leaf axils, and the trifoliate leaves are unmarked. The plant is up to 40 centimetres (1.3 ft) tall, and is found in fields and on roadsides – it is also grown as fodder. It has been linked with toxicity in horses and has some agricultural uses. The plant blooms from spring to autumn. Originating in mainland Europe, it has become established as an introduced plant in the British Isles and throughout the temperate regions of the world.
Trifolium breweri, which has the common names forest clover and Brewer's clover, is a perennial clover that is native to mixed evergreen forests and coastal coniferous forests in Southern Oregon and California.
Trifolium ciliolatum is a species of clover known by the common name foothill clover. It is native to western North America from Washington to Baja California.
Trifolium fucatum is a species of clover known by the common names bull clover and sour clover. It is native to the western United States, where it grows in many types of habitat, becoming common to abundant in some areas. It is an edible species of clover.
Trifolium jokerstii is a rare species of clover known by the common names Jim's clover and Butte County golden clover. It is endemic to Butte County, California, where it is known from eight or nine occurrences near Oroville. It grows in seasonally moist habitat, such as vernal pools, pastures, and ephemeral creeks. It was previously included within the description of Trifolium barbigerum as an odd yellow-flowered variant of a mostly purple-pink-flowered species, and was elevated to species status in 1998. It was named for the California botanist Jim Jokerst.
Trifolium reflexum, the Buffalo Clover, is a species of clover native to the Eastern United States. It is found in areas of natural openings including woodlands, glades, and prairies, often in acidic areas. It is an annual or biennial that produces white to dark pink flowers in the late spring.
Trifolium alpestre, the owl-head clover or purple-globe clover, is a species of flowering plant in the family Fabaceae, native to central, southern and Eastern Europe, the Caucasus, Turkey, and Iran. It reproduces both clonally and by seed.
Symphyotrichum kentuckiense is a rare species of flowering plant in the Asteraceae family and is commonly known as Kentucky aster, Price's aster, Miss Price's aster, Sadie's aster, or lavender oldfield aster. It is a perennial, herbaceous plant that is endemic to broken limestone cedar glades and roadsides in Alabama, Georgia, Kentucky, and Tennessee. It blooms from August through October, reaches heights between 30 centimeters and 100 cm (3.3 ft), and has green to reddish-brown stems. It is a nearly hairless plant with blue to blue-violet ray florets.
