Aquatic and Wetland Vascular Plants of the Northern Great Plains
49. Asteraceae, the Aster Family
4. Boltonia L'Her -- Boltonia1. Boltonia asteroides (L.) L'Her
Stout, erect, glabrous, shortlived perennial 3-11 dm tall, fibrous-rooted, sometimes stoloniferous. Leaves simple, entire, linear to lanceolate or elliptic-lanceolate, 5-18 cm long, 0.5-2(4) cm wide, much smaller in the inflorescence, acute, scabrous on the margin, narrowed to a sessile or weakly clasping base. Heads several to usually numerous in a corymbiform or paniculiform inflorescence, radiate, 1.5-2.5 cm across; ray florets many, pistillate, the ligules white, pink, light blue or lavender, 5-15 mm long; involucres 2.5-5 mm high, the bracts imbricate, scarious-margined with a green midvein, the bracts linear and acute to spatulate and obtuse; receptacle hemispheric or conic, naked; disk florets perfect, their corollas yellow, drying brownish; style branches flattened, with short, lanceolate, hairy appendages. Achenes flattened, obovate, wing-margined, 1.5-2 mm long; pappus of 2 awns and several shorter bristles, reduced or absent in ray achenes. Jul--Aug. Wet meadows, marshes, shores, low prairie and occasionally in wet woods; nw ND to e NE and with one record from the Black Hills, most common in the n part; (NJ to s Man., s to FL and TX; intro. in nw U.S.). B. latisquama A. Gray.
Two varieties occur in this region: var. recognita (Fern. & Griscom) Cronq., with linear, acute-tipped involucral bracts, and var. latisquama (A. Gray) Cronq., with at least the outer bracts spatulate and obtuse-tipped. Many of our plants appear to be intermediate between these two varieties.
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