trailing restharrow

Ononis arvensis, the field restharrow, is a widespread species of flowering plant in the family Fabaceae, native to Eurasia from central Europe through to western Siberia and the western Himalayas. It is a perennial hemicryptophyte usually 50–100 cm (20–39 in) tall, typically found in meadows, but also in old fields and dry grasslands.

It is closely related to Ononis spinosa and Ononis repens, being treated (together with O. repens) by some authors as a subspecies of O. spinosa. It shares pink flower colour with these two; from O. spinosa it differs in having its flowers in pairs at each node rather than singly, and (like O. repens) in lacking stiff spines; the wing petal size is small as in O. spinosa, rather than equalling the keel petal as in O. repens. It has a more easterly distribution than either O. spinosa or O. repens, not being found west of southern Scandinavia and Germany, and extending further into central Asia.