General: Spiny Goldenweed (Xanthisma spinulosum) is an upright, spindly shrub of rocky places that grows 2-3 feet tall and has yellow sunflowers. The lower leaves are spindly and lobed, each lobe with a spine on the tip; the upper leaves are entire. The involucre is broadly hemispheric, and each phyllary is tipped with a spine. The entire plant is covered with short, stiff hairs.

Spiny Goldenweed is a fairly common component of shrub communities on well-drained sandy, gravelly, and rocky soils on upper bajadas and moderate slopes into the lower mountains in the Upper Sonoran (Mojave Desert Scrub and Pinyon-Juniper Woodland) life zone, but generally to the east of Las Vegas. It is possible that this species is moving westward and invading the deserts around Las Vegas.

Family: Sunflower (Asteraceae).

Other Names: sleepydaisy, Texas sleepydaisy, Xanthisma texanum, Xanthisma spinulosum var. gooddingii, Machaeranthera pinnatifida. The Jepson Manual uses the name Machaeranthera pinnatifida, Haplopappus gooddingii.

Plant Form: Upright, drought deciduous shrub.

Height: To about 3 feet.

Bark: Green.

Stems: Upright, somewhat spreading, leafy.

Leaves: Lower leaves narrow, 1-2 inches long, lobed; lobes narrow, each tipped with a spine. Upper leaves smaller, narrow, entire.

Flowers: Blooms spring through summer. Inflorescence: composite heads with disk and ray flowers, one at the tip of each long branch. Involucre hemispheric, about 1/3rd inch long and 2/3rds inch wide. Phyllaries lanceolate, tipped with a bristle, green, glandular and rough to the touch. Flowers: yellow.

Seeds: Tiny achene (like a tiny sunflower seed) with many fine bristles.

Habitat: Dry, well-drained sandy, gravelly, and rocky soils on upper bajadas and moderate slopes in the lower mountains.

Elevation: To about 2,000 feet.

Distribution: California, southern Nevada, Arizona, and northern Mexico.

Comments: This species is regionally variable, and the taxonomy is uncertain.