3c. var. macer (Trin.) Kartesz & Gandhi

S. asper var. macer (Trin.) Shinners

Plants with scaly rhizomes. Flowering stems relatively slender, 0.7–2.2 mm wide toward the base. Uppermost leaf sheath appearing 0.7–2.0(–2.5) wide when folded. Terminal inflorescences relatively lax and often slightly arched or curved, the main branches 7–16, relatively widely spaced and often slightly arched away from the main axis, with 14–40 spikelets per square cm. 2n=36, 38, 40, 42, 46, 48. August–October.

Uncommon in the Unglaciated Plains Division and the southwestern portion of the Ozarks (Missouri to Mississippi west to Kansas and Texas). Upland prairies and margins of dry upland forest.