The
photo at right shows the heart-shaped silicles of this species. Note how they
are obcompressed, and thus like shallow scoops. Photographed at Catherine Creek
in the middle Columbia River Gorge in late April, 2005.
Shepherd's cress is a small annual herb consisting of single erect, simple to freely branched stem arising 5-25 cm high from a cluster of basal leaves. The herbage of the stem and leaves is glabrous. Individual leaves of the basal cluster of leaves are 1.5-5 cm long with long, slender petioles. The blades range from simple with entire margins to pinnatifid with the terminal segment the largest and the several to many lateral lobes smaller. The terminal leaf segment generally is oval, obovate or oblanceolate in shape. The stem is generally leafless, although one to several much-reduced leaves may ge found there.
The inflorescence is a raceme, generally dense upon first bloom, then elongating as the fruit begin to mature. The slender pedicels are spreading and about 4-8 mm long. The 4 sepals are about 0.5 mm long and often are purple-tinged. The 4 white petals are about 1 mm long. Six stamens are present. The fruits are small capsules or silicles from 3-3.5 mm long and not quite as wide. The capsule valves are keeled and slightly winged, especially towards the distal end. The style is ablsent from the capsule.
Shepherd's cress is an introduced species, which is a fairly common weed in disturbed places, especially those which are sandy.
A European species, shepherd's cress may be found in the lowlands to the west of the Cascade Mts. in Oregon and Washington.
In the Columbia River Gorge it may be found between the elevations of 100'-2200' from east of the Sandy River east to near Catherine Creek.