Publication: Sp. Pl. 1: 69-70. 1753.
selected vouchers: WTU
Notes: FNA24: "Poa interior, a native species, grows from Alaska to western Quebec and New York, south to Arizona and New Mexico. It is restricted to the Flora region. It is fairly common from boreal forests to low alpine habitats of the Rocky Mountains. It grows in subxeric to mesic habitats, such as mossy rocks and scree, usually in forests. It is usually tetraploid.
In alpine habitats, Poa interior is often quite short, and often sympatric with P. glauca. It is most reliably distinguished from P. glauca by lemmas that are glabrous between the marginal veins and keels or, rarely, sparsely puberulent on the lateral veins. It usually also differs from P. glauca subsp. rupicola in having at least a few hairs on its calluses. It can be distinguished from P. nemoralis by its longer ligules, lower top culm node, and wider glumes and lemmas. It is sometimes difficult to distinguish from P. palustris, but differs in having lemmas with wider hyaline margins and straight or gradually arched keels, a densely tufted habit, and scantly webbed calluses."