Images: ©Jouko Lehmuskallio
Ononis spinosa ssp. arvensis
- Family: Pea Family – Fabaceae (Leguminosae)
- Height: 30–80 cm (12–30 in.)
- Flower: Corolla irregular (zygomorphic), 15–20 mm (0.6–0.8 in.) long. Petals five: the upstanding the ‘standard’, the lateral two the ‘wings’, the lower two united to form the ‘keel’, overall shape of corolla being butterfly-like, reddish-purple apart from keel which is white. Sepals five, united, sepal-lobes long. A single carpel. Stamens ten. Inflorescence a terminal raceme, or flowers borne in pairs in leaf axils.
- Leaves: Alternate. Trifoliolate or simple, leaflets elliptic, toothed, 1–2.5 cm (0.4–1 in.) long. End leaflet stalked. Stipules large, united with leaf-stalk.
- Fruit: A short 3–5 mm (0.1–0.2 in.), dehiscing, 1–3-seeded legume.
- Habitat: Seashore meadows, waste ground.
- Flowering time: July–August.
Ononis arvensis is a long- and stickily-hairy, stinking perennial. In Finland it occurs at the northern boundary of its distribution. Compared to other restharrows (Ononis spp.), this species has unusual habitat preferences. Its relatives chiefly thrive in dry environments, even steppe and semi-desert. In Finland, O. arvensis grows in seashore meadows, occasionally even on wet sites. The species is severely endangered in Finland, and it is protected.
Ononis arvensis ssp. arvensis, described here, is a subspecies of the spiny restharrow (O. spinosa ssp. spinosa), a pretty rare bush in southern Scandinavia. The other subspecies which also rarely occurs in Finland, is restharrow (ssp. maritima).
