Description

Key Characters:

Growth Form: Annual or biennial herbs, pubescent with simple hairs.

Stems: Stems ascending to erect, 1–5 dm long, ± branched from near base, usually densely hirsute, the hairs coarse.

Roots:

Leaves: Leaves simple. Alternate or rarely opposite. Basal leaves 3–7 cm long, 2–3 times pinnately dissected, the lobes 1–2 mm wide. cauline leaves present up the inflorescence, somewhat reduced, pinnately lobed to deeply serrate, the segments apiculate. Surfaces usually hirsute. Stipules absent.

Flowers: Flowers usually bractless in elongate racemes 3–15 cm long, becoming conspicuously narrowed toward apex. Flowers bisexual (perfect), actinomorphic or rarely slightly irregular; white, pale yellow, or greenish, usually 2–3 mm long, sometimes absent. Calyx of 4 sepals, deciduous, erect, usually oblong, sometimes the inner 2 with gibbous bases that hold the nectar; ca.0.6 mm long, caducous. Corolla of 4 petals, rarely absent, yellow, white, or lavender, entire to emarginate, rarely lobed or fimbriate, usually with an elongate claw; linear, ca. 0.3–0.4 mm long, or absent. Stamens 2; 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; styles short or essentially absent; stigma capitate.

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; flattened at right angles to the septum; broadly ovate to suborbicular; 2.5–3.5 mm long; the apical notch broad; prominent; the margins clearly exceeding the style. Seeds 1 to numerous; often becoming mucilaginous when wet; endosperm essentially absent; ca. 1.5 mm long.

Ploidy: 2n = 64

Habitat:

Elevation Range: