Trifolium arvense L. belongs to the section Trifolium, and is a secondary wild relative of the cultivated crops crimson clover (T. incarnatum L.), and red clover (T. pratense L.) (USDA, ARS, National Genetic Resources Program 2010). The species contains two varieties native to Europe: Trifolium arvense L. var. arvense and Trifolium arvense L. var. gracile (Thuill.) DC. (Zohary and Heller 1980).

European regional assessment: Least Concern (LC)

EU 27 regional assessment: Least Concern (LC)

Trifolium arvense due to its widespread distribution and no major threats, is regionally classified in Europe as Least Concern.

T. arvense has a wide distribution, being native to most of Europe, western and central Asia and northern and northeastern Africa. It has also been naturalised in Australasia, North America and the Azores (USDA, ARS, National Genetic Resources Program 2010). In France it is widespread, recorded in all departments except Lot to the south (Association Tela Botanica 2010). In the UK it has a relatively widespread distribution throughout England and Wales (Preston et al. 2002). Its distribution within Scotland becomes patchier further north and is largely absent in the northwest (Preston et al. 2002). Its distribution in Northern Ireland is also limited, occurring in only 23 localities (Preston et al. 2002) and in Ireland it is confined to coastal areas around the country, occurring in only 33 localities (Preston et al. 2002).

The exact population size is unknown, but the species is considered common across Europe from Britain to Iran and throuhout north Africa. It is found in a variety of habitats and populations are stable.

T. arvense grows in open, pioneer plant communities, as well as meadows, fields, roadsides and wastelands. It is an annual legume, and flowers between March and May (Zohary and Heller 1984).

In the UK this lowland species is able to grow in open rocky or sandy habitats which include acidic heathlands, sea cliffs and sand dunes (Preston et al. 2002). In addition, this species grows on railway ballast, inland waste ground, disturbed grassland and set-aside fields where it prefers light, sandy soils (Preston et al. 2002).

There appears to be no major threats and this species is found in several habitats which are not threatened within its range.

In the UK, according to Preston et al. (2002) there has been a widespread decline of this species in the southeast of England since 1950.

T. arvense is a secondary crop wild relative and potential gene donor to the cultivated crops crimson clover (T. incarnatum L.), and red clover (T. pratense L.) (USDA, ARS, National Genetic Resources Program 2010). Natural wild populations are grazed by wild and domesticated animal species.

Trifolium arvense is specifically listed in Annex I of the International Treaty on Plant Genetic Resources for Food and Agriculture as part of the forage legume gene pool so warrants specific conservation attention.

Ex situ seed samples are available in numerous gene banks with the largest collections being held by the N.I. Vavilov All-Russian Scientific Research Institute of Plant Industry Russian Federation, Aegean Agricultural Research Institiute (Menemen, Turkey), ICARDA (Aleppo, Syria) and University of Aberystwyth (Aberystwyth , UK) gene banks. 53 accessions are being held currently at the Regional Plant Introduction Station in Washington, USA (USDA, ARS, National Genetic Resources Program 2010).

EURISCO reports 176 germplasm accessions held in European genebanks, 90 of which are reported to be of wild or weedy origin. Of the wild accessions, 64 originate from within Europe (EURISCO Catalogue 2010).

In situ the species is likely to be passively conserved in many existing protected areas in throughout its range but as its conservation in these sites is not actively monitored it may be subject to population loss over time from factors such as climate change.

Classified as Least Concern (LC) in Denmark (Den Danske Rødliste 2010).