Description

Key Characters:

Growth Form: Glabrate and somewhat glaucous annual herbs 3–12 dm tall, branched above, with watery and usually pungent sap.

Stems:

Roots:

Leaves: Leaves simple. Alternate or rarely opposite. Lower blades lyrate–pinnatifid, 10–20 cm long, 5–8 cm wide, upper leaves reduced, eventually becoming linear–lanceolate. Margins usually entire. Sessile, not clasping the stem. Stipules absent.

Flowers: Flowers in usually bractless, in elongate, terminal racemes. Flowers bisexual (perfect), actinomorphic or rarely slightly irregular; showy. Calyx of 4 sepals, ascending or spreading, deciduous, erect, usually oblong, inner ones ± gibbous at base. Corolla of 4 petals, rarely absent, yellow, 8–12 mm long, long–clawed. Stamens (2–4)6(–16), tetradynamous, the inner 4 usually in pairs, sometimes connate at base in pairs; anthers dithecal, opening by longitudinal slits. Ovary superior, 2(4?)-carpellate, usually 2-celled by means of a false, but usually complete septum, rarely 1-celled, sessile or rarely stipitate; ovules 1 to numerous, borne on parietal placentas on replum margin at periphery of ovary wall, campylotropous or occasionally anatropous; style 1 or occasionally absent; stigma truncate or 2-lobed.

Fruit: Capsules divided into 2 cells by the usually thin and membranous septum; elongate (at least 3 times as long as wide) and referred to as a silique. fruit an elongate; linear silique; often torulose; terete (cylindrical) or 4–angled; with a stout; indehiscent; flat or conical; often 1–seeded beak. Siliques erect; spreading; (2–)3–4 cm long; the beak 4–9 mm long. Seeds 1 to numerous; often becoming mucilaginous when wet; endosperm essentially absent; seeds brownish red; globose; 1.5–2 mm in diameter; the surface inconspicuously reticulate.

Ploidy: 2n = 36

Habitat:

Elevation Range: