Compilation
Gamochaeta sphacelata

Annuals, 10–35(–50) cm; usually taprooted, rarely fibrous-rooted. Stems erect to ascending, densely gray-white pannose. Leaves basal and cauline, basal usually withering before flowering; blades linear to narrowly oblanceolate (often folded along midveins), 1–4 cm × 1–3(–5) mm (distally becoming ± patent, arcuate bracts surpassing the heads), faces concolor or weakly bicolor, pannose-tomentose (± equally grayish to whitish, basal cells of hairs on adaxial faces persistent, expanded, glassy). Heads in terminal glomerules 1 cm or in interrupted, spiciform arrays 2–14 cm × 10–12(–14) mm (pressed; glomerules sometimes axillary). Involucres cylindro-campanulate, 3.5–4(–5) mm, sparsely arachnose. Phyllaries in (3–)4–5 series, outer triangular, lengths 1/3–1/2 inner, apices (brown) acute-acuminate (usually inrolled and spreading or recurved), inner triangular-lanceolate, laminae purplish (in bud) to whitish or silvery (in fruit), apices (usually striate) acute (not apiculate). Florets: bisexual 3–5; all corollas usually purplish distally. Cypselae (tan) 0.5–0.6 mm.