This widespread southeastern species extends north to the southern Great Lakes region (FNA 25, K). It appears generally distinct, and no segregates are recognized. A few Ky. colls. (e.g. from POWE at KY) may be transitional to polyanthes. Elsewhere, hybrids with acuminatum and laxiflorum are also known (FNA 25). There is a proposed segregate largely restricted to the Coastal Plain, from Del. to Mo., potentially treated as D. inflatum (Scribn. & Smith) J.R. Thomas; this tends to be relatively tall, with looser sheaths, more elongated ligule, narrower leaves with lewer marginal hairs, smaller spikelets and more freely branching autumnal culms (F, HC,; Thomas 2017). However, HC stated that "many intergrades occur"; and W has not recognized it.