The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Cascade rock-cress, Columbia Gorge rockcress, fork-hair rock-cress

Habit Perennials; (caudex simple or branched, covered with persistent petiolar remains); glabrous or sparsely pubescent, trichomes simple or short-stalked, forked (0.3–1 mm), these rarely mixed with fewer, unequal 3-rayed ones.
Stems

simple or few from base (caudex), erect, usually unbranched, rarely branched (few) distally, (0.7–)1–3.8(–4.5) dm, (glabrous throughout or sparsely pubescent basally to distally).

Basal leaves

petiole (0.4–)1–3(–4.5) cm, (glabrous or sparsely ciliate);

blades oblanceolate, spatulate, or obovate, (0.7–)1.2–3 cm × 5–17(–22) mm, margins entire or dentate, (often ciliate), apex obtuse, surfaces glabrous or sparsely pubescent, trichomes short-stalked, forked and simple.

Cauline leaves

(2 or) 3–5 (or 6);

blade linear, oblong, obovate, or oblanceolate, 0.7–3(–4) cm × 3–8 mm, base cuneate, not auriculate, margins usually entire, rarely few-toothed, apex obtuse, surfaces usually glabrous, rarely margins ciliate.

Racemes

simple, (dense or lax).

Flowers

sepals (greenish), oblong, 3–4 × 1.5–2 mm, (usually glabrous, rarely with few trichomes subapically), lateral pair saccate basally;

petals white, spatulate, 7–11 × 2.5–4 mm, apex rounded;

filaments 3.5–5 mm;

anthers oblong, 0.8–1 mm.

Fruiting pedicels

suberect, ascending, or divaricate, (2–)4–17(–22) mm, (glabrous).

Fruits

ascending to suberect, (not appressed to rachis), slightly torulose, sometimes slightly curved, strongly flattened, (2–)2.5–4(–4.6) cm × 1.7–2.2 mm;

valves each with prominent midvein extending full length;

ovules 14–26 per ovary;

style 0.5–1.2(–1.6) mm, (slender).

Seeds

winged distally, oblong to broadly ovate, (1.5–)1.8–2.5(–3) × 1–1.3 mm;

wing (0.2–)0.4–0.8(–1) mm wide.

Arabis furcata

Phenology Flowering May–Jul(-Aug).
Habitat Open slopes, alpine meadows, cliffs, ridge crests
Elevation (50-)1000-2100 m ((200-)3300-6900 ft)
Distribution
from FNA
OR; WA
[WildflowerSearch map]
[BONAP county map]
Discussion

Arabis furcata is known in Washington from Chelan, Kittitas, Klickitat, Okanogan, Skamania, and Yakima counties, and in Oregon from Clackamas, Hood River, Multnomah, and Wasco counties.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 7, p. 262.
Parent taxa Brassicaceae > tribe Arabideae > Arabis
Sibling taxa
A. aculeolata, A. alpina, A. blepharophylla, A. caucasica, A. crucisetosa, A. eschscholtziana, A. georgiana, A. mcdonaldiana, A. modesta, A. nuttallii, A. olympica, A. oregana, A. patens, A. pycnocarpa
Synonyms A. suksdorfii
Name authority S. Watson: Proc. Amer. Acad. Arts 17: 362. (1882)
Web links