MorphologyRead full entry
DescriptionAnnuals or short-lived perennials, 30–80(–110) cm; taprooted. Stems persistently tomentose, not glandular. Leaf blades mostly linear, 3–6 cm × 1.5–3.5 mm (sometimes smaller distally), bases not clasping, decurrent 5–15 mm, margins flat, faces concolor, loosely tomentose, not glandular. Heads usually in loose, paniculiform arrays. Involucres turbinate-campanulate, 5–6 mm. Phyllaries in (4–)5–6(–7) series, white (opaque, dull to shiny), ovate to ovate-oblong (inner usually with filiform keel and slight apiculum), glabrous. Pistillate florets (39–)44–69. Bisexual florets 5–8(–11). Cypselae ridged, smooth or weakly papillate-roughened. 2n = 14.