Grassland agoseris

Stylopappus grandiflorus Nuttall, Trans. Amer. Philos. Soc., n. s. 7: 432. 1841

Stems usually 0, rarely weakly de-veloped. Leaves erect to ascending; petioles often purplish, margins ciliate to tomentose; blades usually linear to oblanceolate, rarely spatulate, 10–40(–50) cm, margins usually dentate to lobed, or laciniately pinnatifid, rarely subentire, lobes 3–5 pairs, opposite to irregular, linear to lanceolate, usually antrorse, sometimes spreading; lobules often present, faces ± villous to canescent. Peduncles elongating after flowering, (15–)25–60(–96) cm in fruit, ± glabrate, or apically villous to tomentose, eglandular, sometimes bracteate. Involucres campanulate to hemispheric, 2–5 cm in fruit. Phyllaries in 4–5 series, green or medially rosy purple and/or spotted, subequal to unequal, margins occasionally dentate, ciliate or lanate, sometimes glabrous, faces glabrous or hairy, eglandular; outer subequal to or surpassing inner at flowering, spreading, adaxially tomentose; inner erect, greatly elongating after flowering. Receptacles epaleate. Florets 40–500; corollas yellow, tubes 4–7(–10) mm, ligules 3–7 × ca. 1 mm; anthers 1–3 mm. Cypselae 9–28 mm, bodies fusiform, 3–7 mm, beaks 9–21 mm, lengths mostly 3–4 times bodies; ribs ridged to subalate, rarely nerviform, straight, ± glabrous; pappus bristles in 2–3 series, 7–15 mm. 2n = 18.

Varieties 2 (2 in the flora): w North America.