Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Rosids
Order: Fabales
Family: Fabaceae
Subfamily: Faboideae
Tribe: Trifolieae
Genus: Medicago (bur clovers)
Species: M. lupulina
Binomial name: Medicago lupulina
Common name: Black medick, Nonesuch, Hop clover, Black nonesuch, Black medic clover, Hop medic, Black clover, Black hay, blackweed, Hop trefoil.
Medicago lupulina is an annual or short-lived perennial plant growing each year from adventitious buds on the roots. Mature plants measure from fifteen to eighty centimetres in height, with fine stems often lying flat at the beginning of growth and later erecting. The leaves are compound, each with three oval leaflets, carried on a short petiole; the centre leaflet usually has a longer petiole. The leaflets are hairy, toothed toward the tip, and they end in a short point.
Medicago lupulina has small yellow flowers, often grouped in tight bunches, and typically measuring between two and four millimetres in diameter; but on larger plants, the flowers may reach eight millimetres or more. The flowers are hermaphrodite (have both male and female organs) and are pollinated by bees, Lepidoptera and by itself.
The fruit is a small, ovoid pod, between one and two millimetres in length, that does not open upon maturation, but hardens and turns black when ripe. Each pod contains a single amber-coloured seed.
Like other legumes, the roots of Medicago lupulina contain nodules hosting nitrogen-fixing bacteria. Plants that survive for more than one year may develop a deep taproot.
Medicago lupulina is a native of the old world and is found throughout Europe, North Africa, the near east, and most of Asia, including India, China, and Korea. It is naturalized in central Asia, Japan, South Africa, Australia, New Zealand, the United States, Hawaii, Alaska, Canada, and much of South America.
It is resistant to cold and can be found in some areas up to 1,800 m.a.s.l. It thrives in dry to moist, well-drained soils containing sand, loam, or clay, and is a pioneer plant, often growing on disturbed ground. It is found in grassland, pastures, vegetable and agronomic crop fields, orchards, vineyards, gardens, lawns, roadsides and other disturbed, unmanaged places.
Thanks to Wikipedia for text and information:
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