Boechera canadensis (L.) Al-Shehbaz (redirected from: Arabis canadensis)
Family: Brassicaceae
[Arabis canadensis L.]
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Biennials; short-lived; sexual; caudex not evident. Stems 1 per plant, arising from center of rosette near ground surface, 2.5-10(-12.5) dm, sparsely to densely pubescent proximally, trichomes simple, to 1 mm, glabrous or sparsely pubescent distally. Basal leaves: blade obovate to oblanceolate, 10-30 mm wide, margins dentate, ciliate proximally, trichomes simple, to 1 mm, surfaces moderately pubescent, trichomes simple, 0.5-1.5 mm, these mixed with smaller, 2- or 3-rayed ones. Cauline leaves: 12-20, often concealing stem proximally; blade auricles absent or proximalmost blades with auricles 0.5-2(-5) mm, surfaces of distalmost leaves sparsely pubescent. Racemes 15-65(-82)-flowered, sometimes branched. Fruiting pedicels descending to horizontal, usually curved, rarely straight, 6-13(-17) mm, pubescent or glabrous, trichomes subappressed, usually 2-rayed. Flowers divaricate-ascending to horizontal at anthesis; sepals pubescent; petals white, 3-5 × 0.7-1.2 mm, glabrous; pollen ellipsoid. Fruits pendent to horizontal, not appressed to rachis, often secund, curved, edges parallel, 4-10 cm × 2.5-4 mm; valves glabrous; ovules 40-62 per ovary; style 0.3-0.8(-1.1) mm. Seeds uniseriate, 1.7-3.5 × 1.5-2.2 mm; wing continuous, 0.4-1 mm wide distally. 2n = 14.

Flowering Apr-Jul. Bluffs, rocky slopes, ravines, open woods; 0-1200 m; Que.; Ala., Ark., Conn., D.C., Fla., Ga., Ill., Iowa, Kans., Ky., Maine, Md., Mass., Mich., Minn., Miss., Mo., Nebr., N.Y., N.C., Ohio, Okla., Pa., Tenn., Tex., Vt., Va., W.Va., Wis.

Biennial herb to 1 m tall

Stem: upright, unbranched or sparingly branched.

Flowers: in elongated, loosely branched clusters, white or yellowish white, 3 - 5 mm long, 1 mm wide, barely exceeding sepals. Petals four. Stamens six.

Fruit: a narrow pod, spreading, drooping or hanging downward, 7 - 11 cm long, 2 - 3.5 mm wide, on a 7 - 12 mm long stalk, flat, curved, prominently veined. Seeds in one row, 3 mm long, as wide as the valve, with a 0.5 - 1 mm wide wing.

Lower leaves: alternate, stalked, to 10 cm long, lance- to spatula-shaped, sparsely toothed, sparsely hairy.

Upper leaves: alternate, stalkless, smaller than lower leaves, lance-shaped to elliptic or oblong, narrow at the base, sparsely and irregularly toothed, hairy.

Similar species: Boechera canadensis is the only Boechera species in the Chicago Region without lobed leaf bases.

Flowering: late May to mid-July

Habitat and ecology: In the Chicago Region, Boechera canadensis is most often found in the shade of dune woods, on sloping ground. It also occurs in mesic forest. It was found in Kenosha County, Wisconsin in disturbed woods.

Occurence in the Chicago region: native

Etymology: Boechera refers to the Danish botanist, Tyge Bocher. Canadensis refers to Canada, but is also used in reference to North America (a result of early French influence).

Author: The Morton Arboretum

Stout biennial to 1 m, sparsely hairy at base; cauline lvs lanceolate to elliptic or oblong, 3-10 cm, narrowed to the base, chiefly sharply and remotely dentate, ±hairy; pet 3-5 mm; pedicels erect in bud, widely divergent at anthesis, in fr reflexed and 7-12 mm; frs pendulous, flat, ±curved, 7-11 cm נ2-3.5 mm, prominently veined; seeds in 1 row, 3 mm long, as wide as the valve, the wing 0.5-1 mm wide; 2n=14. Woods; Me. to Minn., s. to Ga. and Tex. May-July.

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

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