23. Symphyotrichum turbinellum (Lindl. ex Hook.) G.L. Nesom (prairie aster)

Aster turbinellus Lindl.

Pl. 229 f, g; Map 1035

Plants perennial herbs, with a compact, woody, sometimes short-branched, usually horizontal rootstock. Stems 1 to several, 40–120 cm long, with few to more commonly several ascending to spreading branches above the midpoint, sparsely pubescent toward the tip, usually in lines or bands, with spreading, often stout and stiff (sandpapery) hairs, glabrous toward the base or sometimes nearly the entire length. Basal as well as lower to median stem leaves often absent at flowering, sessile to short-petiolate, the blade 4–12 cm long, 0.5–2.0 cm wide, narrowly oblanceolate to narrowly oblong-oblanceolate, tapered at the base, rounded or angled to a bluntly or sharply pointed tip, the margins entire or sparsely toothed and relatively strongly roughened, the upper surface often somewhat shiny, glabrous, the undersurface sparsely roughened with short, stout hairs along the midvein, otherwise glabrous, the secondary veins on the leaf undersurface usually relatively faint, fused into an irregular network, the veinlets also forming a dense, irregular network of short to elongate areoles. Median and upper stem leaves variable, more or less progressively smaller toward the stem tip, sometimes abruptly smaller in the inflorescence, sessile, not clasping or sheathing the stem, the blades 2–12 cm long, linear to narrowly lanceolate, narrowly elliptic, lanceolate, or elliptic, tapered at the base, angled or tapered to a sharply pointed tip, the margins usually entire, otherwise similar to the lower stem leaves. Inflorescences appearing as open panicles, sometimes with relatively long, loosely racemose branches, the heads appearing mostly long-stalked, the bracts usually noticeably shorter and narrower than the adjacent foliage leaves, 0.2–0.7(–1.2) cm long, narrowly lanceolate or narrowly elliptic to more commonly linear. Heads mostly 2–3 cm in diameter (including the extended ray corollas) at flowering. Involucre 7–12 mm long, the bracts in 6–9 unequal, overlapping series. Involucral bracts narrowly oblong-oblanceolate to oblanceolate, rounded or broadly angled to a bluntly pointed tip (the innermost series sometimes with an abrupt, short, sharp point at the tip), the tip ascending, the base somewhat thickened and keeled, the slender midvein broadened relatively abruptly in the apical 1/5–1/3 into a broadly elliptic to diamond-shaped or obovate green tip with relatively broad, white to straw-colored margins nearly to the tip, these often also somewhat purplish-tinged toward the tip, the outer surface glabrous or less commonly sparsely hairy toward the tip, the margins usually finely hairy, especially toward the tip. Ray florets 14–20 in 1 series, the corollas well developed, 10–16 mm long, lavender to purple to bluish purple. Disc florets 15–30, the corollas 4.5–6.5 mm long, the slender portion of the tube shorter than the slightly expanded apical portion, the lobes 0.6–0.9 mm long, 17–22 percent of the total length of the expanded portion. Pappus bristles 4.5–6.0 mm long, off-white to light tan, rarely purplish-tinged. Fruits 2–3 mm long, with 4 or 5 longitudinal ribs, purplish brown to brown, sparsely hairy. 2n=96. August–November.

Scattered nearly throughout the state, but apparently absent from most of the western half of the Glaciated Plains Division (Nebraska to Oklahoma east to Illinois and Louisiana). Openings of mesic to dry upland forests, savannas, glades, and ledges and tops of bluffs; also railroads and roadsides; often on acidic substrates.

Steyermark (1963) noted that this showy species does well in cultivation and should be grown more widely as an ornamental in gardens. Barkley (1986) stated that the colloquial name prairie aster seems inappropriate for this species, as it does not grow in prairies in the Great Plains. The same can be said for Missouri, where this is mostly a woodland species. Presumably, farther east it grows more frequently in grassland communities.