Clovers, also called trefoils, 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 the 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.
A shamrock is a type of clover, used as a symbol of Ireland. Saint Patrick, one of Ireland's patron saints, is said to have used it as a metaphor for the Christian Holy Trinity. The name shamrock comes from Irish seamróg, which is the diminutive of the Irish word seamair and simply means "young clover".
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.
The four-leaf clover is a rare variation of the common three-leaf clover that has four leaflets instead of three. According to traditional sayings, such clovers bring good luck, a belief that dates back to at least the 17th century. The earliest example of this idea may be from the 1620 play Astologaster, by Sir John Melton. The 1640 Theatrum Botanicum mentions a "fower-leafed or purple grasse" that was kept in gardens because it was "good for the purples in children or others".
Oxalis acetosella, the wood sorrel or common wood sorrel, is a rhizomatous flowering plant in the family Oxalidaceae, common in most of Europe and parts of Asia. The specific epithet acetosella refers to its sour taste. The common name wood sorrel is often used for other plants in the genus Oxalis. In much of its range it is the only member of its genus and hence simply known as "the" wood sorrel. While common wood sorrel may be used to differentiate it from most other species of Oxalis, in North America, Oxalis montana is also called common wood sorrel. It is also known as Alleluia because it blossoms between Easter and Pentecost, when the Psalms which end with Hallelujah are sung.
Trifolium pratense, red clover, is a herbaceous species of flowering plant in the bean family, Fabaceae. It is native to the Old World, but planted and naturalised 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".
Medicago lupulina, commonly known as black medick, nonesuch, or hop clover, is a plant of dry grassland belonging to the legume or clover family. Plants of the genus Medicago, or bur clovers, are closely related to the true clovers (Trifolium) and sweet clover (Melilotus). Like the true clovers, black medick has three leaflets and a small, yellow flower closely resembling those of lesser trefoil. Black medick belongs to the same genus as alfalfa.
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.
Colias philodice, the common sulphur or clouded sulphur, is a North American butterfly in the family Pieridae, subfamily Coliadinae.
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 glomeratum is a species of clover known by the common names clustered clover and bush clover. It is native to Eurasia and North Africa and it is known elsewhere as an introduced species. It easily takes hold in disturbed areas, becoming a common weed. It is an annual herb growing decumbent to upright in form with mostly hairless herbage. The leaves are made up of oval leaflets up to 1.2 centimeters in length. The inflorescences occur in leaf axils, each a headlike cluster of many flowers. Each flower has a calyx of sepals with triangular points that bend outward, and a pink corolla.
Trifolium macrocephalum is a species of clover known by the common name largehead clover or bighead clover native to the Great Basin region of the western United States.
Trifolium occidentale, the western clover, is a clover plant belonging to the genus Trifolium in the legume family, Fabaceae. Its flowers are white, similar to white clover, with which it has long been confused. This species lives almost exclusively in sand dunes and sea cliffs on the Atlantic coast of Europe, especially Cornwall and the Channel Islands. The species was first described in 1961 by Dr David E Coombe of Cambridge University.
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.
Hypera nigrirostris, commonly known as the lesser clover leaf weevil, is a species of weevil that is native to Europe and northern Africa and has been introduced to North America and Japan. Both adults and larvae feed on red clover and other plants in the family Fabaceae.
Trifolium parryi, commonly known as Parry's clover or Parry clover, is a high altitude species of plant from the western United States. It grows in the Rocky Mountains from southern Montana to northern New Mexico. It is a short plant that is adapted to the harsh conditions and short growing season near and above timberline.
