94. Carex mesochorea Mack.

Pl. 55 l–o; Map 210

C. cephalophora Muhl. ex Willd. var. mesochorea (Mack.) Gleason

Plants with poorly developed rhizomes, forming tufts or clumps. Flowering stems 15–95 cm long, shorter than to more commonly longer than the leaves. Leaf blades 2–30 cm long, 2.5–5.0 mm wide, green to light green, with a dense covering of minute papillae (visible only with magnification) on one or both surfaces. Leaf sheaths tight around the stem, the ventral side relatively firm and without cross-wrinkles, usually remaining intact at maturity, the dorsal side green, lacking white areas or mottling, the ligule shorter than wide and U- or V-shaped. Inflorescence compact, ovate in outline, dense and headlike, the 3–8 spikes difficult to distinguish, the lowermost bracts 4–20 mm long, shorter than the inflorescence, hairlike with the base broadened. Spikes 5–7 mm long, 5–9 mm wide, with 8–22 ascending to spreading perigynia, the scales 1.8–3.1 mm long, 2/3 as long to about as long as the perigynia, ovate to elliptic, the tip sharply pointed and mostly short-awned. Perigynia 2.9–3.7 mm long, 1.6–2.5 mm wide, up to 2 times as long as wide, elliptic-ovate in outline, widest just below the middle, the tip with a short beak with minutely toothed or roughened margins, the base rounded to broadly narrowed, the basal portion not thickened with corky to spongy tissue, light green to straw-colored, the ventral surface nerveless, the dorsal surface nerveless or with 1–4 faint nerves. Stigmas relatively short, slender, mostly straight. Fruits 1.5–2.0 mm long, broadly ovate to nearly circular in outline. April–August.

Scattered nearly throughout Missouri, but apparently absent from western portions of the Glaciated Plains Division (northeastern U.S. and adjacent Canada west to Nebraska and Kansas; apparently introduced in California). Mesic to dry upland forests and upland prairies; also pastures, roadsides, and railroads.

Carex mesochorea is superficially very similar to C. cephalophora but tends to be a more robust plant with fewer, larger spikes and larger perigynia and fruits. In Missouri, it is less common than C. cephalophora.