Lomatium tuberosum Hoover

Lomatium tuberosum Hoover, Leafl. W. Bot. 4: 39. 1944
Plants short-caulescent, 1-2.5 dm. high, from a tuberous horizontal or vertical root bearing leaf-sheaths which are neither fibrous nor persistent, glabrous and glaucous; leaves cuneate in general outline, excluding the petioles 4—8 cm. long, ternate, then 3-4-pinnate, the ultimate divisions linear, herbaceous, 3-6 mm. long; petioles 7-12 em. long, sheathing at the base; cauline leaf solitary or wanting, reduced or bladeless; peduncles exceeding the leaves; involucel of few, inconspicuous, narrowly linear bractlets; rays 5-8, divergent, 2-8 cm. long; pedicels 7-14 mm. long, the umbellets 8-12-flowered; flowers purple, the anthers yellow; fruit oblongoval, 9-11 mm. long, 4.5-6.5 mm. broad, glabrous, the wings less than 1 mm. broad, fleshy.
Type locality: "Hills south of White Swan," Yakima County, Washington, R. F. Hoover 5726.
Distribution: Known only from the vicinity of the type locality (Hoover 5603).