7. Rudbeckia missouriensis Engelm. ex C.L. Boynton & Beadle (Missouri coneflower)

Pl. 287 f, g; Map 1223

R. fulgida Aiton var. missouriensis (Engelm. ex C.L. Boynton & Beadle) Cronquist

Plants perennial, with fibrous to somewhat fleshy roots and stout rhizomes (new basal rosettes occurring immediately adjacent to the older stems). Stems 20–50(–80) cm long, moderately to densely pubescent with relatively long, spreading hairs, not glaucous. Leaves all unlobed, tapered or angled at the base, only slightly expanded at the base and inconspicuously wrapping around the stem, the margins entire or with a few inconspicuous, sharp teeth, the surfaces moderately to densely hairy with mostly spreading minutely pustular-based hairs, usually moderately roughened to the touch, not glaucous, green to grayish green when fresh. Basal and lowermost stem leaves often present at flowering (or present on adjacent rosettes), more or less sessile to short- or less commonly long-petiolate, the blade 5–20 cm long, 5–20 mm wide, broadly linear to oblanceolate or narrowly spatulate, rounded or more or less angled to a bluntly pointed tip. Median and upper stem leaves sessile, the blade 2–15 cm long, 4–10 mm wide, linear to narrowly oblong-lanceolate, angled or short-tapered to a bluntly or sharply pointed tip. Inflorescences usually appearing as strongly ascending clusters. Involucral bracts 10–20, 6–14 mm long, ovate to lanceolate or occasionally linear, both surfaces sparsely to densely hairy, the margins usually with moderate to dense, ascending hairs. Receptacle 8–15 mm long, 10–17 mm in diameter, hemispherical at the start of flowering, then elongating somewhat and sometimes becoming ovoid. Chaffy bracts subtending only the disc florets, shorter than the disc florets (including the corolla), short-tapered to a broadly triangular, usually sharply pointed tip, the outer surface glabrous (sometimes sparsely hairy toward the base) and often somewhat shiny, the margins usually glabrous. Ray florets 9–15, the corolla 10–25 mm long, relatively slender, spreading to slightly drooping at flowering, yellow or less commonly the basal portion orangish- or reddish-tinged, the outer surface sparsely to moderately short-hairy. Disc florets numerous, the corolla 3.5–4.5 mm long, greenish yellow toward the base, dark purple to purplish brown toward the tip, the lobes ascending at flowering. Stigma lobes relatively short and bluntly pointed at the tip. Pappus a minute rim or crown. Fruits 1.5–3.0 mm long. 2n=38. June–October.

Scattered in the Ozark and Ozark Border Divisions (Oklahoma to Texas east to Illinois, Kentucky, and Louisiana). Glades, ledges and tops of bluffs, rock outcrops in upland prairies, and rocky openings of dry upland forests, rarely banks of streams; also roadsides, usually on limestone and dolomite substrates.

This species is recognized by its relatively low stature, often large colonies of dense rosettes, narrow leaves, strongly ascending branches, and relatively small heads.