Lomatium cuspidatum

Lomatium cuspidatum is a perennial herb of the family Apiaceae, native to the U.S. state of Washington. It is found primarily on open rocky slopes in the Wenatchee Mountains, strongly associated with serpentine scree and soils.

Description

Plants are small, usually less than 20 cm tall. Foliage has a blue-gray to green color, and is held on thick fleshy stalks. Leaves are fleshy and are dissected into leaflets that have a sharp extended tip, referred to by the species name cuspidatum. Flowers appear early in the growth season and are held above the foliage in a compound umbel on thick fleshy stalks that arise from the base of the plant. The flowers are brownish purple to brownish red in color.
Similar plants with yellow flowers and flatter leaflets that grow in the northern Wenatchee Mountains on non-serpentine soil are now classified as a distinct species Lomatium roneorum.

Range and Ecology

Lomatium cuspidatum is endemic to serpentine regions of the Wenatchee Mountains in Washington State. It grows on seasonally dry sunny slopes composed mostly of small loose rocks and unstratified soils that are largely derived from serpentinite rock. Due to seasonal dryness, slope instability, and the unusual mineral composition of serpentine-related rocks, such slopes support a sparse and very restricted flora, including four species found only in this region. Several other plants are less narrowly restricted but are notably associated with serpentine soils and bedrock outcrops in the Wenatchee Mountains, including Polystichum lemmonii, Ivesia tweedyi, Androsace nivalis, Adiantum aleuticum, Aspidotis densa, Galium serpenticum, and Claytonia megarhiza.