General: Grass Family (Poaceae). Kentucky bluegrass is a cool-season perennial sod-forming grass. The roots are shallow, often within the upper 8 cm of the soil surface. Stems are 30 to 90 cm tall. Leaves are attached to the base of the stem, folded and sometimes hairy at the point of attachment, have flat blades, are 2 to 5 mm wide and 10 to 40 cm long. The inflorescence is an open panicle consisting of two to six flowers. The lemmas have a tuft of cobwebby hairs. Flowering starts in May and fruit is mature by mid-June.

Kentucky bluegrass is distinguished from Canada bluegrass (Poa compressus) by its darker green foliage, longer leaves, and pubescence at the bases of the leaves.

Distribution: Kentucky bluegrass is native to portions of North America, including areas within the United States. Exact delineation of native status has not been determined, but data seems to indicate that it is native in parts of the southeast, northeast, and upper Midwest regions and introduced or naturalized elsewhere. It occurs throughout the United States although it is most prevalent in the northern half. It is not common in the Gulf States or in the desert regions of the southwest. For current distribution, please consult the Plant Profile page for this species on the PLANTS Web site (http://plants.usda.gov).

Habitat: Kentucky bluegrass is promoted on sites that have cool and humid climates. It is found in uplands and lowlands of the tallgrass prairie and in the lowlands of mixed-grass prairies where adequate precipitation falls. In the west, it is found on northern exposures at mid to high elevations. In the southwest and California, it is found in cool mountainous regions.

It frequently occurs as an understory dominant in aspen habitats throughout the Intermountain Region, ponderosa pine, sagebrush/bunchgrass, and bunchgrass habitats throughout the U.S., and riparian habitats in the Mountain West. It is also a common dominant of Midwestern prairies.