| Author | Michaux | |
| Distribution | Mostly the Piedmont and Sandhills; scattered elsewhere across the state, though likely absent in the southeastern Coastal Plain and the northern Mountains.
VT to SD, south to FL and TX. | |
| Abundance | Frequent to common in most of the Piedmont and Sandhills; uncommon in the northern and central Coastal Plain, and rare in the Mountains. Probably absent from the northwestern and southeastern parts of the state. | |
| Habitat | Dry open sandy or rocky soil of roadsides, railroad margins, clearings, rock outcrops, other disturbed ground. As its name suggests, it inhabits Midwestern prairies, but seems not to be especially tied to prairie-like habitats or glades in NC. | |
| Phenology | Flowering and fruiting August-October. | |
| Identification | Prairie Three-awn is distinguished by its widely branching, ascending (mostly not erect) stems and noticeably long awns. The widely-branched stems give the plant a broad, "bushy" appearance. Aristida tuberculosa looks superficially like it, but it is erect and taller, with a denser inflorescence occupying only the upper third of the plant. | |
| Taxonomic Comments | None
The genus Aristida is most notable for the 3 hairlike awns which project from each floret. The central awn is almost always thicker than the other 2 awns. The awns may stand erect, especially during the early flowering period, but in most species eventually are bent parallel to the ground. In some species, only the central awn is bent, while the other 2 remain erect. In some species, all awns are the same length, while in other species the central awn is distinctly longer. The awns have tiny barbs which catch onto hair and fur, and florets will even hitch a ride up the inside of your pants! | |
| Other Common Name(s) | Oldfield Three-awn | |
| State Rank | S5 | |
| Global Rank | G5 | |
| State Status | | |
| US Status | | |
| USACE-agcp | | |
| USACE-emp | | |
