General: Smooth Threadleaf Ragwort (Senecio flaccidus var. monoensis) is a common desert subshrub or perennial forb with upright stems and bright yellow sunflowers. The leaves are highly dissected, thread-like, and somewhat fleshy. Main phyllaries in a single row.

Smooth Threadleaf Ragwort is a common component of desert vegetation communities in the Upper Sonoran (Mojave Desert Scrub and Pinyon-Juniper Woodland) life zone. Around Las Vegas, look for this species in Red Rock Canyon NCA, and keep an eye out for it along highway edges.

Family: Sunflower (Asteraceae).

Other Names: green groundsel, Mono groundsel, Mono ragwort, Senecio.

Plant Form: Perennial forb, subshrub with upright stems.

Height: To about 2 feet.

Stems: Upright.

Leaves: Blades highly dissected, thread-like, somewhat fleshy.

Flowers: Blooms during spring and early summer. Inflorescence: flowerhead growing from stem tips. Flowers: yellow ray and disk flowers. Main phyllaries in a single row; also a row of outer phyllaries that are short and bent outward. Receptacle naked, pappus of bristles.

Seeds: Achene with bristly pappus.

Habitat: Desert washes, hillsides, and bajadas into the lower mountains.

Elevation: About 1,500 to 6,000 feet.

Distribution: California to Utah and Texas.

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