Trifolium pratense (from Latin prātum, meaning meadow), 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 naturalized in many other regions.
Trifolium pratense was initially published by Carl Linnaeus in his book Species Plantarum on page 768 in 1753.
The genus has 3 known subspecies:[1]
Red clover is a herbaceous, short-lived perennial plant, which is generally variable in size, growing to NaN0NaN0 tall. It has a deep taproot which makes it tolerant to drought and gives it a good soil structuring effect.[2] The leaves are alternate, trifoliate (with three leaflets), each leaflet NaN1NaN1 long and NaN1NaN1 broad, green with a characteristic pale crescent in the outer half of the leaf; the petiole is NaN1NaN1 long, with two basal stipules that are abruptly narrowed to a bristle-like point. The flowers are dark pink with a paler base, NaN1NaN1 long, produced in a dense inflorescence, and are mostly visited by bumblebees.[3]
The red clover is native to Europe, Western Asia, and northwest Africa, but it has been naturalized in other continents, like North and South America. Specifically, the red clover was brought to Argentina and Chile over 100 years ago, although it is not clear how exactly it was introduced.[4] The red clover has become increasingly important as a source of economic stability in Chile, which has made the need for pollinators even more important.[5] One important pollinator, which was also brought from Europe, is Bombus ruderatus, or the large garden bumblebee. This bumblebee has been one of the important pollinators of red clover in South America and other countries such as New Zealand.[6] In India the highest producer of Red Clover seed is the Agriculture Department of Kashmir's Fodder Seed Production Station Aru, in south Kashmir's Anantnag district of Jammu & Kashmir.[7] Two red clover accessions were deposited in National Gene Bank of India from Fodder Seed Production Station Aru in 2019 vide IC-635999 and IC-636000 by ICAR.[8]
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 T. pratense var. sativum. It has become naturalised in many temperate areas, including the Americas and Australasia as an escape from cultivation.
Due to its beauty, it is used as an ornamental plant. Red clover's flowers and leaves are edible, and can be added as garnishes to any dish.[9] They can be ground into a flour.
The flowers often are used to make jelly and tisanes, and are used in essiac recipes. Their essential oil may be extracted and its unique scent used in aromatherapy.
Trifolium pratense
In the traditional medicine of India, Trifolium pratense is believed to be a deobstruent, antispasmodic, expectorant, sedative, anti-inflammatory and antidermatosis agent.[11]
In alternative medicine, red clover is promoted as a treatment for a variety of human maladies, including symptoms of menopause, coughs, disorders of the lymphatic system and a variety of cancers. There is some evidence it may reduce the frequency of hot flushes in menopausal women.[12] There is no good evidence it is of any benefit in preventing or treating cancer or any other diseases.[13]
Due to its coumarin derivatives, T. pratense should be used with caution in individuals with coagulation disorders or currently undergoing anticoagulation therapy.[14] It is metabolised by CYP3A4 and therefore caution should be used when taking it with other drugs using this metabolic pathway.[15]
See main article: List of red clover diseases. Red clover is subject to bacterial as well as fungal diseases, including clover rot,[16] and red clover rust, Uromyces trifolii-repentis var. fallens. Other problems include parasitic nematodes (roundworms) and viruses.
Trifolium pratense is the state flower of Vermont.[17] It has also been used as the national flower of Denmark. In 1936 the Ministry of Foreign Affairs announced it was the national flower as part of an international exhibition taking place in Argentina. However, the choice did not become popular with the public. In 1987 the daisy, specifically either the marguerite daisy (Argyranthemum frutescens) or oxeye daisy (Leucanthemum vulgare), replaced it as the nation's floral emblem.[18] [19]