The hybrid of Cyperus lupulinus with C. schweinitzii is C. ×mesochorus Geise. It is occasionally encountered with the two parent species in the north-central states (Illinois, Indiana, Michigan, Minnesota, and Wisconsin) and has been recorded once from Quebec. The hybrid is similar in size to C. schweinitzii; it has fewer rays, inflorescence bracts 30–45º above horizontal, and floral scales with mucros 0.4–0.5 mm.
Cyperus lupulinus, the Great Plains flatsedge, is a plant species native to North America. It is widespread across southeastern Canada and the central and northeastern United States as far west as Wyoming, Colorado and New Mexico, with more isolated populations reported in Washington (Asotin County), Idaho (Idaho County) and Oregon (Wallowa County). It grows in open, sun-lit locations such as fields, prairies, roadsides, farms, etc.[2][3]
Cyperus lupulinusis a perennial herb up to 50 cm tall, spreading by means of underground rhizomes. Culms are triangular in cross-section. Spikes are densely clustered into a more or less spherical clump. Achenes are dark brown, almost black, egg-shaped, about 2 mm across.[2][4][5][6][7][8]
Two subspecies are accepted:[1][2]
Cyperus lupulinus, the Great Plains flatsedge, is a plant species native to North America. It is widespread across southeastern Canada and the central and northeastern United States as far west as Wyoming, Colorado and New Mexico, with more isolated populations reported in Washington (Asotin County), Idaho (Idaho County) and Oregon (Wallowa County). It grows in open, sun-lit locations such as fields, prairies, roadsides, farms, etc.
