Clover
From Free net encyclopedia
- For other uses, see Clover (disambiguation).
{{Taxobox | color = lightgreen | name = Clover | image = Trefle2.1s.JPG | image_width = 240px | image_caption = clover inflorescence | regnum = Plantae | divisio = Magnoliophyta | classis = Magnoliopsida | ordo = Fabales | familia = Fabaceae | subfamilia = Faboideae | genus = Trifolium | genus_authority = L. | subdivision_ranks = Species | subdivision = See text. }}
Clover (Trifolium) is a genus of about 300 species of plants in the pea family Fabaceae. They are found chiefly in northern temperate regions, but also, like many other north temperate genera, on mountains in the tropics. The plants are small annual or perennial herbs with trifoliate (rarely 5- or 7-foliate) leaves, with stipules adnate to the leaf-stalk, and heads or dense spikes of small red, purple, white, or rarely yellow flowers; the small, few-seeded pods are enclosed in the calyx. Eighteen species are native in Britain, and several are extensively cultivated as fodder-plants. The most widely cultivated clovers are White clover Trifolium repens and Red clover Trifolium pratense.
Other closely related genera often called clovers include Melilotus (sweet clover) and Medicago (alfalfa or 'calvary clover').
The scientific name derives from the Latin tres, "three", and folium, "leaf", so called from the characteristic form of the leaf, which has three leaflets (trifoliate); hence the popular name trefoil. Clovers are used as food plants by the larvae of some Lepidoptera species - see list of Lepidoptera which feed on Clovers.
A common idiom is "to be in clover", meaning to be living a carefree life of ease, comfort, or prosperity. Also, specimens of Shamrock and other clovers are not infrequently found with four leaflets. These four-leaf clovers, like other rarities, are considered lucky.
Contents |
Cultivation
Image:Trifolium-repens.jpg Clover, either sown alone or in mixture with rye-grass, has for a long time formed a staple crop for soiling, for several reasons: it grows freely, shooting up again after repeated mowings; it produces an abundant crop; it is palatable to and nutritious for livestock; it grows in a great range of soils and climates; and it is appropriate either for pasturage or soiling. Except on certain rich calcareous clay soils, it has now, however, become an exceedingly precarious crop. The seed germinates as freely as ever, when it is genuine, but this is unfortunately rare.
In many areas, farmers formerly found that the clover had either entirely disappeared by mid-spring, or is found only in capricious patches here and there over the field. This "clover-sickness", particularly prevalent in England, was sometimes found to result from the depletion of soluble potassium from the subsoil, although insects or fungus could also be to blame (Armsby, Science p.146, 1883)[1]. When crop rotations were managed so that clover does not recur at shorter intervals than eight years, it was found to grow with much of its pristine vigour.
Clover sickness in more recent times may be linked to pollinator decline. Beekeepers are often in heavy demand from farmers with clover pastures, who want bees placed on their farms, as farmers observe the increased reseeding that occurs with increased bee activity.
Species
|
|
|
|
Image:Red clover close 800.jpg T. incarnatum, Crimson or Italian clover, though not hardy enough to withstand the climate of Scotland in ordinary winters, is a most valuable forage crop in England. It is sown as quickly as possible after the removal of a grain crop at the rate of 20-22 kg/ha. It is found to succeed better when only the surface of the soil is stirred by the scarifier and harrow than when a ploughing is given. It grows rapidly in spring, and yields an abundant crop of green food, peculiarly palatable to live stock. It is also suitable for making into hay. Only one cutting, however, can be obtained, as it does not shoot again after being mown.
T. repens, White or Dutch clover, is a perennial abundant in meadows and good pastures. The flowers are white or pinkish, becoming brown and deflexed as the corolla fades. T. hybridum, Alsike or Swedish clover, is a perennial which was introduced early in the 19th century and has now become naturalized in Britain. The flowers are white or rosy, and resemble those of the last species. T. medium, meadow or zigzag clover, a perennial with straggling flexuous stems and rose-purple flowers, is of little agricultural value.
Other British species are: T. arvense, Hare's-foot trefoil; found in fields and dry pastures, a soft hairy plant with minute white or pale pink flowers and feathery sepals; T. fragiferum, Strawberry clover, with densely-flowered, globose, rose-purple heads and swollen calyxes; T. procumbens, Hop trefoil, on dry pastures and roadsides, the heads of pale yellow flowers suggesting miniature hops; and the somewhat similar T. minus, common in pastures and roadsides, with smaller heads and small yellow flowers turning dark brown. The last named is often called Shamrock.
Uses
Image:White clover flower.jpg Clovers are a valuable survival food, as they are high in protein, widespread, and abundant. They are not easy to digest raw, but this can be easily fixed by boiling for 5-10 minutes. Dried flowerheads and seedpods can also be ground up into a nutritious flour and mixed with other foods. Dried flowerheads also steeped in hot water for a healthy, tasty tea.
References
- This article incorporates text from the Encyclopædia Britannica Eleventh Edition{{#if:{{{article|}}}| article {{#if:{{{url|}}}|[{{{url|}}}}} "{{{article}}}"{{#if:{{{url|}}}|]}}{{#if:{{{author|}}}| by {{{author}}}}}}}, a publication now in the public domain.bg:Детелина
da:Kløver de:Klee es:Trifolium fi:Apilat fr:Trèfle it:Trifolium ja:クローバー ko:토끼풀속 lt:Dobilas lv:Āboliņš nl:Klaver nn:Kløver os:Æртæсыфæг pl:Koniczyna ru:Клевер sv:Klövrar vi:Cỏ ba lá (Trifolium) zh:三叶草属