This occurs on relatively deep acid soils in southeastern states. In Ky. it is largely restricted to remnants of original grassland. It is usually distinct in its relatively large spikelets (3.7-4.3 mm long), long ligules (2-5 mm), and robust habit; but see notes under malacophyllum, which may intergrade. These two species plus oligosanthes and scribnerianum have been considered by some authors to form a natural group (section Oligosantha) that differs from the acuminatum, dichotomum and ensifolium groups as follows (FNA 25): spikelets 2.5-4.3 mm long (versus 0.8-3 mm), usually obovoid and turgid (versus ellipsoid or obovoid, not turgid); upper glumes usually with an orange or purple spot at base (versus lacking), and with more prominent veins. However, initial analysis of DNA suggests that ravenelii is nested within the acuminatum complex (Majure et al. 2023).