Prairie or cattail gayfeather

Lacinaria pycnostachya (Michaux) Kuntze

Plants (40–)60–120(–180) cm. Corms globose, sometimes becoming elongate rhizomes. Stems glabrous or densely piloso-puberulent. Leaves: basal and proximal cauline 3–5-nerved, linear to narrowly oblanceolate or oblanceolate, 110–220 × 4–10(–12) mm, gradually then abruptly reduced distally (bractlike proximal to heads), essentially glabrous or sparsely pilose to densely piloso-puberulent, weakly gland-dotted (bases of basal usually fibrous-persistent). Heads in dense, spiciform arrays. Peduncles usually 0, rarely (spreading to ascending) 1–2 mm. Involucres campanulate-cylindric, 7–9(–10) × 3.5–5 mm. Phyllaries (reflexed or curving-spreading) in 4–5 series, oblong-lanceolate, unequal, essentially glabrous or ± pilose, margins with hyaline borders, sometimes ciliate, apices usually acute to acute-acuminate (sometimes distally dilated, nearly petaloid). Florets (4–)5–8; corolla tubes glabrous inside. Cypselae 3.8–4.5(–5) mm; pappi: lengths ± equaling corollas, bristles barbellate.

Varieties 2 (2 in the flora): e United States.