Short Rayed Alkali Aster

Annuals or sometimes perennials, 5–140 cm. Stems 1–6+, decum­bent to erect (straight), glabrous. Leaves thin, margins entire (basal sometimes serrulate), sometimes ciliate or remotely scabrous, acute to ± obtuse, faces glabrous; basal withering by flowering, petiolate, blades oblanceolate to spatulate, 20–115 × 2–15 mm [cult.], bases attenuate; proximal cauline withering by flowering; cauline subpetiolate or sessile (distal), blades oblanceolate to linear, 10–80 × 1.5–10 mm, reduced distally, bases cuneate. Heads (radiate) in narrow, paniculiform to spiciform arrays, branches often in axils of nearly every leaf, ascending. Peduncles glabrous, bracts linear. Involucres narrowly campanulate, 5–9 mm. Phyllaries in 3–4 series, ± spreading, oblong-oblanceolate or -lanceolate to obovate, subequal to ± unequal, linear-lanceolate or linear (innermost), bases scarious, margins narrowly scarious, hyaline, erose, ciliolate, green zones (outer) foliaceous, (inner) lanceolate, apices obtuse to rounded, inner acute, mucronulate, faces glabrous. Ray florets 90–110 in 4–5+ series; corollas pink to pinkish white, laminae 1.5–2 × 0.1–0.2 mm (surpassing style branches, barely surpassing disc corollas; tubes ± 3 mm). Disc florets ± 37; corollas yellow, 4.4–5.2 mm, barely ampliate, tubes much longer than cylindric limbs, lobes lanceolate, ± 0.3 mm. Cypselae tan, obovoid, ± compressed, 2 mm, 2–3-nerved, faces strigillose; pappi white to yellowish, 6.3–7.5 mm. 2n = 14.

Tripolium frondosum Nuttall, Trans. Amer. Philos. Soc., n. s. 7: 296. 1840; Aster frondosus (Nuttall) Torrey & A. Gray; Brachyactis frondosa (Nuttall) A. Gray

Symphyotrichum frondosum (formerly Aster frondosus) is a species of flowering plant in the family Asteraceae native to western North America. Commonly known as short-rayed alkali aster, it is an annual or perennial herbaceous plant that may reach 140 centimeters (55 inches) tall.