It is an herbaceous, short-lived perennial plant, variable in size, growing to 20–80 cm tall. The leaves are alternate, trifoliate (with three leaflets), each leaflet 15–30 mm long and 8–15 mm broad, green with a characteristic pale crescent in the outer half of the leaf; the petiole is 1–4 cm long, with two basal stipules. The flowers are dark pink with a paler base, 12–15 mm long, produced in a dense inflorescence.
Red clover is subject to bacterial as well as fungal diseases. Other problems include parasitic nematodes (roundworms) and viruses.
It is widely grown as a fodder crop, valued for its nitrogen fixation, which increases soil fertility. For these reasons it is used as a green manure crop. Several cultivar groups have been selected for agricultural use, mostly derived from var. sativum. It has become naturalised in many temperate areas, including the Americas and Australasia as an escape from cultivation.
Warnings and contraindications
In alternative medicine, red clover is promoted as a treatment for a variety of human maladies, including coughs, disorders of the lymphatic system and a variety of cancers. However, according to the American Cancer Society, "available clinical evidence does not show that red clover is effective in treating or preventing cancer, menopausal symptoms, or any other medical conditions."
Dietary amounts of red clover are safe, but medicinal quantities may cause rash-like reactions, muscle ache, headache, nausea, vaginal bleeding in women, and slow blood clotting.
Due to its activity on estrogen receptors, red clover is contraindicated in people with a history of breast cancer, endometriosis, ovarian cancer, uterine cancer, uterine fibroids, or other estrogen-sensitive conditions, but others have suggested the high isoflavone content counteracts this, and even provides benefits in these conditions.
There is evidence that red clover may cause infertility.
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- Other National Symbols - Embassy of Denmark India
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