Mapping is provisional. In its narrow sense, typical acuminatum occurs on the Coastal Plain and through Central to South America (FNA 25). Records from Ky. need to be rechecked, but at least the colls. from LIVI (KY) and PIKE (NCU) appears correctly identified. This taxon has been reported to intergrade locally with lanuginosum and others in the acuminatum group (FNA25), but analysis of Thomas (2015) suggests that it is generally distinct. He noted that acuminatum has dense pubescence on stems and leaves, plus a double ligule consisting of a short true ligule backed by a conspicuous pseudoligule [usually with longer hairs]. In addition, unlike others of the section, it has conspicuous marginal cilia that typically extend at least half way up the margins of vernal leaf blades (versus in the basal quarter). "These marginal hairs have pustulate bases that can be detected even in older specimens that have lost the hairs; abaxial hairs are easily misinterpreted as originating from the margin, so caution and microscopy are recommended."