17. Eragrostis spectabilis (Pursh) Steud. (purple love grass)

Pl. 149 a, b; Map 605

E. spectabilis var. sparsihirsuta Farw.

Plants perennial, with knotty bases and sometimes with short rhizomes, forming tufts or small clumps. Flowering stems 25–75 cm long, erect to spreading, sometimes somewhat arched, glabrous. Leaf sheaths with a tuft or line of hairs at the tip and usually along the upper portion of margins, glabrous to hairy on the back, the ligule 01.–0.4 mm long. Leaf blades 15–45 cm long, 3–8 mm wide, flat or with the margins inrolled, hairy at the base and occasionally also on the rest of the surfaces. Inflorescences open, broad panicles 15–45 cm long, often more than 1/2 the length of the entire plant, usually broadly ovate in outline, the branches loosely ascending to stiffly spreading, the axis and branches strongly roughened and with short tufts of hair in the axils of the main branches. Spikelets 4–7 mm long, 1.0–2.5 mm wide, with slender, but stiff, long stalks, spreading from the branches, with (5–)7–12 perfect florets. Pattern of disarticulation with the glumes usually shed eventually after the lemmas, paleas, fruits, and joints of the rachilla have been shed, the entire inflorescence sometimes also breaking off at the base. Lower glume 1–2 mm long, ovate, usually somewhat roughened along the midnerve. Upper glume 1.4–2.2 mm long, ovate, usually somewhat roughened along the midnerve. Lemmas 1.5–2.5 mm long, elliptic‑ovate, sharply pointed at the tip, keeled, the lateral nerves relatively conspicuous, roughened along the midnerve. Anthers 0.3–0.5 mm long. Fruits 0.6–0.8 mm long, broadly elliptic in outline, somewhat flattened, brown. 2n=40, 42. July–October.

Common nearly throughout the state (eastern U.S. and adjacent Canada west to North Dakota and Texas; Mexico, Central America). Upland prairies, sand prairies, loess hill prairies, glades, tops of bluffs, openings of mesic to dry upland forests, and savannas; also pastures, fallow fields, roadsides, railroads, and dry, open, disturbed areas.

This grass frequently forms dense stands of pinkish‑purple‑tinged plants along roadsides. At maturity, the inflorescence frequently becomes detached from the rest of the plant at the base and is dispersed by wind as a “tumbleweed.” Most of the Missouri material has the leaf sheaths glabrous on the back.