[Skeletonweeds: The Genera Lygodesmia, Pleiacanthus and Prenanthella East of the Cascade Mountains of Oregon and Washington]

Spiny Skeletonweed

Pleiacanthus spinosus

Synonyms: Lygodesmia spinosa, Stephanomeria spinosa

Spiny Skeletonweed: Pleiacanthus spinosus (Synonyms: Lygodesmia spinosa, Stephanomeria spinosa)

Spiny skeletonweed from the clifftops at the western edge of Warner Peak, Hart Mt. National Antelope Refuge.........August 29, 1997.

Characteristics:

Spiny skeletonweed is a perennial with several stems, which are many-branched. The branches are rigid and very spiny tipped. The lower leaves are linear and entire, less than 3 cm long. The flowers are pink to reddish-purple, the heads consisting of 3 to 5 ray flowers.

Habitat:

Dry, exposed rocky areas.

Range:

Spiny skeletonweed is found scattered throughout the west from southern British Columbia, south to the east of the Cascade Mts to California, and eastward to western Montana and Arizona.

Spiny skeletonweed observed along the Fremont National Recreation Trail #160 at about 7400' on the southeastern shoulder of Crook Peak, Fremont-Winema National Forest.......July 17, 2022.

Spiny skeletonweed observed along the Fremont National Recreation Trail #160 at about 7400' on the southeastern shoulder of Crook Peak, Fremont-Winema National Forest.......June 28, 2019.

A view of the spines of spiny skeletonweed from the clifftops at the western edge of Warner Peak, Hart Mt. National Antelope Refuge.........August 29, 1997.

Paul Slichter