Hare's Ear Mustard

Foodplant / spot causer
colony of Pseudocercosporella anamorph of Mycosphaerella capsellae causes spots on live leaf of Conringia orientalis

Sometimes a weed of cultivated fields. Young sprouts are edible and seed contain fatty oil.

Annual or biennial up to 60 cm tall often branched from below erect, glabrous subglaucous. Lower leaves variable in size, obovate cuneate at the base, subsessile or sessile ± entire, apex rounded or obtuse; upper leaves oblong to suborbicular, cordate, amplexicaul, entire; all leaves fleshy ± glaucous, glabrous or sometimes apparently slightly papillose. Racemes 10-25-flowered, lax, up to 20 cm long in fruit. Flowers c. 1 cm across, whitish or pinkish; pedicel up to 10 mm (rarely-15 mm) long in fruit, slightly thickened. Sepals 5-7 mm long, 1.5 mm broad, oblong inner pair ± saccate at the base. Petals 8-12 mm long, 3.5-4 mm broad, obovate, narrowed into a claw. Stamens c. 7: 8 mm long; anthers c. 1.5 mm long. Siliquae tetragonous, spreading, straight or curved, 60-90 (-120) mm long, 2-2.5 mm broad, with a prominent mid-rib on the valves, shortly, beaked; beak 1-2.5 mm long, thickened with capitate stigma, giving a blunt apex to the fruit; seeds 12-20 in each locule, 2-2.5 mm long, oblong, dark brown, finely papillose; radicle incumbent.

Distribution: S. and C. Europe, N. Africa, Turkey, Caucasus, Iraq, Iran, Afgha¬nistan and W. Pakistan.

Fl.Per.: April-May.

Conringia orientalis is a species of flowering plant in the mustard family known by the common name hare's ear mustard. It is native to Eurasia but it is known elsewhere as an introduced species and sometimes a noxious weed. It is weedy in its native range and also in North America, where it is a widespread invasive species, especially in central Canada.

It is an annual herb producing an unbranched erect stem 30 to 70 centimetres (12 to 28 inches) in height. The thick, waxy leaves are generally oval in shape, up to 9 centimetres (3+1⁄2 inches) long, and clasp the stem at their bases. The flower is enclosed in pointed sepals and has yellow, clawed petals about 1 centimetre (1⁄3 inch) long. The fruit is a beaded silique up to 13 centimetres (5 inches) long. The plant is known to be toxic to livestock.