Sinapis arvensis, L.

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1964, Flora Europaea - Volume 1. Lycopodiaceae to Platanaceae, Cambridge University Press : 339

1. S. arvensis L. , Sp. Pl. 668 (1753)

(incl. S. orientalis L. , 5. schkuhriana Reichenb.).

Annual; stems up to 80 cm, usually hispid at least below, sometimes glabrous. Leaves up to 20 cm, usually hispid; lower stalked, lyrate, with large, coarsely toothed terminal lobe, usually with several smaller lateral lobes; upper leaves sessile, usually simple, lanceolate. Siliqua 25-45(-55) x (l-5-)2'5-4 mm, patent; valves glabrous (or with short, stiff, deflexed hairs, var. orientalis (L.) Koch & Ziz ); beak 10-15 mm, straight. Seeds usually 8-13, reddish-brown or blackish. 2n = 18. A weed o farable land. Native probably in the Mediterranean region, but introduced throughout Europe, becoming rarer in the north. All except Az Sb; only casual in Fa Is.

Var. orientalis (L.) Koch & Ziz is as widespread as the type.