Ethnobotany. A food for the Paiute Peoples. The peeled roots were eaten raw or pit cooked and boiled or dried for future use. According to Kelly, Isabel T. in “Ethnography of the Surprise Valley Paiute” (1932).
Description. The plants of that species of tuberous lomatium are acaulescent and 15 to 60 cm high at maturity. Simple or branched stems (one or several) arise from roots, of brown color, which are elongate and slender or which are tuberous above and elongate below – the tuberous portion being globose to ovoid, up to 3,5 cm long and 2,5 cm wide. The leaves are ternately and pinnately divided and dissected – the ultimate leaf segments being 0,3 to 6 mm long and 0,2 to 1 mm wide with mucronulate apices. The leaf blades are 9 to 14 cm long, glabrous to scaberulous and their general outline is broadly obovate. The green to purplish tinged petioles are wholly sheathing and from 2 to 7 cm long. The inflorescence is an umbel consisting of 4 to 20 rays which are 2 to 13 cm long. The narrowly elliptic bracts (2 to 10) are 2 to 10 mm long and 0,2 to 1 mm wide with acute apices. Each umbellet consists of 10 to 20 flowers which are all yellow: petals, anthers and smooth stylopodia. The ovaries are glabrous. The oblong-linear to narrowed elliptic fruits are 9-17 mm long and 1,5-5 mm wide and possess 2 to 6 oil canals in the intervals and 2 oil canals in the commissures. Their pedicels are 1-3 mm long at maturity. Their lateral wings are 0,2 to 0,5 mm wide.
Phenology. The flowering period is from late April through June and the maturing of the fruits range from early-May to mid-September.
Territories. Blue Mountains of southeastern Washington; much of eastern Oregon to the east of the Cascade Mountains; north-eastern California to central and southern Idaho and northern Nevada ; disjunct to Carbon County in Wyoming, to Gunnison, Rio Blanco, and Routt counties in Colorado, and to the Grand Canyon in northern Arizona. Lomatium bicolor is composed of two varieties Lomatium bicolor var. leptocarpum and Lomatium bicolor var. bicolor – leptocarpum describing a variety with narrower fruits borne on shorter pedicels, more slender roots and fewer linear leaf segments. In Idaho, some populations of Lomatium bicolor are problematic because their morphological features seem to partake of both varieties.