Clover or trefoil are common names for plants of the genus Trifolium, consisting of about 300 species of flowering plants in the legume or pea 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 cm tall. The leaves are trifoliate, monofoil, bifoil, cinquefoil, hexafoil, septfoil, etcetera, 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.
A shamrock is a young sprig, used as a symbol of Ireland. Saint Patrick, Ireland's patron saint, is said to have used it as a metaphor for the Christian Holy Trinity. The name shamrock comes from Irish seamróg[ˈʃamˠɾˠoːɡ], which is the diminutive of the Irish word seamair óg 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. According to traditional sayings, such clovers bring good luck, though it is not clear when or how this idea began. The earliest mention of "Fower-leafed or purple grasse" is from 1640 and simply says that it was kept in gardens because it was "good for the purples in children or others". A description from 1869 says that four-leaf clovers were "gathered at night-time during the full moon by sorceresses, who mixed it with vervain and other ingredients, while young girls in search of a token of perfect happiness made quest of the plant by day". The first reference to luck might be from an 11-year-old girl, who wrote in an 1877 letter to St. Nicholas Magazine, "Did the fairies ever whisper in your ear, that a four-leaf clover brought good luck to the finder?"
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, the 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 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 northwestern Europe, from Ireland east to Belgium. 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 dubium, the lesser trefoil, suckling clover, little hop clover or lesser hop trefoil, is a flowering plant in the pea and clover family Fabaceae. This species is generally accepted as the primary plant to represent the traditional Irish shamrock.
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. 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.
Norfolk Roadside Nature Reserve is a scheme which was set up in the mid-1990s by collaboration between the Norfolk County Council and the Norfolk Wildlife Trust. The aim of this scheme is to protect and promote the verges of Norfolk's roadside, that contain rare and scarce plant and insect species. Many of Norfolk's roadside verges have survived modern road improvements and as such are remnants of the natural grassland habitats that were once common and widespread in the British Isles. There are currently 67 such sites around the Norfolk countryside, but more are added each year. Once each year every Roadside Nature Reserve is surveyed and recorded by a dedicated group of volunteers from the trust. Demarcation posts are sited at each end of the Reserves.
Colias philodice, the common sulphur or clouded sulphur, is a North American butterfly in the family Pieridae, subfamily Coliadinae.
Trifolium angustifolium is a species of clover known by the common names narrowleaf crimson clover, narrow clover and narrow-leaved clover.
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 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.
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.
