Aster Linnaeus subsect. Chapmaniani Semple, Phytologia 58: 429. 1985; Eurybia (Cassini) Cassini sect. Chapmaniani (Semple) G. L. Nesom

Perennials, eglandular; usually short-rhizomatous, sometimes with caudices. Stems not brittle at maturity, glabrous. Leaves: basal persistent to flowering, petiolate (petioles sometimes marcescent), blades 1-nerved, linear to linear-lanceolate sparsely denticulate or entire; cauline sessile, blades linear, bases clasping or subclasping. Heads radiate. Phyllaries unequal (bases indurate), green zones narrowly lanceolate (faces sparsely villous). Rays florets 8–23 in 1 series; laminae (10–)14–15(–20) × 0.8–2.2 mm. Disc corollas ± ampliate, throats funnelform to narrowly campanulate, lobes erect. Cypselae obovoid, compressed, 8–10(–14)-nerved, glabrous. x = 7.

Species 1: se United States.

SELECTED REFERENCE

Semple, J. C. 1982. Observations on morphology and cytology of Aster hemisphaericus, A. paludosus, and A. chapmanii (Asteraceae) with comments on chromosomal base number and phylogeny of Aster subg. Aster sect. Heleastrum. Syst. Bot. 7: 60–70.

Lower Taxon

• Symphyotrichum chapmanii (Torrey & A. Gray) Semple & Brouillet