Border Goldthread - Thelesperma subnudum
Other Names:
Thelesperma marginatum
Native Species
Global Rank:
G5
State Rank:
S4
C-value:
3
Agency Status
USFWS:
USFS:
BLM:
External Links
Glabrous perennial from a branched caudex. Stems erect, simple, 10–25 cm. Leaves cauline, opposite; lower petiolate, deeply 3-lobed; lobes linear-lanceolate, 1–3 cm long; upper reduced, simple. Inflorescence of 1 to 3 terminal heads; peduncles 2–15 cm long. Heads discoid; involucre hemispheric, 6–9 mm high; phyllaries in 2 very unequal series; the inner narrowly ovate, striate, scarious-margined, united below; outer short, often reflexed; receptacle flat with a scale subtending each flower. Disk flowers perfect, yellow; corollas 4–6 mm long, tube shorter than the throat; style branches flattened. Pappus of 2 minute awns or absent. Achenes cylindric, compressed, glabrous, 5–7 mm long, enclosed in the scale (
Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).
Our plants are variety
marginatum (Rydb.) Cronquist.