53. Carex lupulina Muhl. ex Willd. (hop sedge)

Pl. 44 a–d; Map 169

C. lupulina var. pedunculata A. Gray

Plants often with long-creeping, dark brown rhizomes, forming clumps or scattered tufts. Vegetative stems generally poorly developed or absent. Flowering stems 1 to few per tuft, 20–130 cm long, smooth, light brown to somewhat reddish tinged at the base. Leaf blades 15–65 cm long, 4–15 mm wide, dull green. Leaf sheaths slightly prolonged past the insertion point of the blade, truncate or slightly convex at the tip, the ligule longer than wide and V-shaped, the uppermost leaf (not a bract subtending a spike) with the sheath 1.5–25.0 cm long. Staminate spike 15–85 mm long (rarely a second, shorter, staminate spike at the base of the terminal one), 1–5 mm wide, nearly sessile to long-stalked, but the stalk shorter than to about as long as the uppermost pistillate spike. Staminate scales 7–15 mm long, narrowly oblanceolate to lanceolate, tapered to a pointed or awned tip, straw-colored with a green midrib and white margins. Pistillate spikes 1–5, 15–65 mm long, 13–30 mm wide, ascending, ovate to broadly elliptic in outline, with 8–80 perigynia. Pistillate scales 6–15 mm long, lanceolate to narrowly ovate, tapered to a pointed or rough-awned tip, straw-colored with a green midrib and white margins. Perigynia 11–19 mm long, mostly ascending, narrowly ovate in outline, green or sometimes yellowish brown at maturity, somewhat shiny, glabrous, the tip with the beak 6–10 mm long, the base rounded. Styles strongly contorted near the base. Fruits with the main body 3.0–4.0(–4.5) mm long, longer than wide, diamond-shaped in outline, widest at the middle, the angles narrowly rounded, the sides flat or nearly so. 2n=56. May–September.

Scattered to common nearly throughout Missouri (eastern U.S. west to Minnesota, Nebraska, and Texas; Canada). Swamps, bottomland forests, marshes, sloughs, bottomland prairies, moist depressions of upland prairies, and margins of streams, ponds, and sinkhole ponds; also along ditches; sometimes emergent aquatics.

This is the commonest species of section Lupulinae in Missouri. It occupies the broadest range of habitat types and is also the most variable morphologically.