Slickrock Biscuitroot

Lomatium laevigatum (Nutt.) Coult. & Rose, Contr. U. S. Nat Herb. 7: 225. 1900.
Peucedanum laevigatum Nutt.; T. & G. Fl. N. Am. 1: 627. 1840. Cogswellia laevigata M. E. Jones, Contr. W. Bot. 12: 32. 1908.
Plants caulescent, 2.5-3.7 dm. high, tufted at the base, glabrous; leaves ovate in general outline, excluding the petioles 7-12 cm. long, ternate, then 2-3-pinnate, the ultimate divisions distinct, linear, 5-35 mm. long, 1-3 mm. broad, acute, minutely apiculate; petioles 0.5-1.5 dm. long, sheathing below; peduncles exceeding the leaves; involucel usually wanting; rays 9-20, ascending, 0.7-4.5 cm. long, unequal; pedicels 4-10 mm. long, the umbellets 10-30-flowered; flowers yellow; fruit oblong, 6-10 mm. long, 4-6 mm. broad, the wings slightly narrower than or equaling the body; oil-tubes solitary in the intervals, 2 on the commissure.
Type locality: Blue Mountains, Oregon, Nuttall,
Distribution: Columbia River Valley, Washington and Oregon (Howell J 505, Thompson 6388),'

Lomatium laevigatum, commonly known as slickrock biscuitroot, is a perennial herb of the Apiaceae family. It grows in basalt cliffs east of the Cascades crest in south-central Washington to Oregon. Its range is limited and considered threatened in Washington State.