Helenium amarum

Annuals, 10–100 cm. Stems 1–3(–15), usually branched distally, not winged, glabrous or sparsely hairy. Leaves glabrous or sparsely hairy; basal blades linear to ovate, entire or pinnately toothed or lobed to pinnatifid; mid and distal blades linear, entire. Heads (1–)10–150(–250+) per plant, in paniculiform arrays. Peduncles 3–11 cm, sparsely hairy. Involucres hemispheric to globose or globoid, 5–9 × 6–10 mm. Phyllaries moderately to densely hairy. Ray florets 8–10, pistillate, fertile; corollas yellow, 4.5–14 × 2–10 mm. Disc florets 75–250+; corollas yellow proximally, yellow to yellow-brown or purple distally, 1.6–2.7 × 0.8–1.2 mm, lobes 5. Cypselae 0.7–1.3 mm, moderately to densely hairy; pappi of 6–8 entire, aristate scales 1–1.8 mm.

Distribution

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• Legacy Map

se United States, n Mexico.

Discussion

Varieties 2 (2 in the flora).

Selected References

None.

Lower Taxa

Helenium amarum var. amarum, Helenium amarum var. badium

Key

1	Basal and proximal cauline leaves usually withered by flowering; basal blades usually entire or pinnately toothed, sometimes pinnatifid; proximal blades usually entire, sometimes pinnately toothed; disc corollas yellow to yellow-brown distally	Helenium amarum var. amarum
1	Basal and proximal cauline leaves often present at, sometimes withered by, flowering; basal blades pinnatifid; proximal blades entire or pinnately toothed or lobed to pinnatifid; disc corollas purple distally	Helenium amarum var. badium