1. Culms terete or several-ridged, smooth; anthers 1.1–2.5 mm long (not including a short prolonged tip); body of achenes 1.5–1.7 mm long.
1. Culms 3-angled, scabrous; anthers 0.6–1.1 mm long; achenes various.
2. Perianth bristles ciliate, slightly or not at all exceeding the blunt achene; scales of spikelet not more than 7; achenes ca. 1.6–1.8 mm long.
2. Perianth bristles smooth, several times as long as the apiculate achene at maturity; scales of spikelets slightly more than 7; body of achene less than 1.5 mm long.
All species found in Trichophorum
MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. May 28, 2020. https://www.michiganflora.net/genus.aspx?id=Trichophorum.