Abstract for CM051

Great Plains Mixedgrass Prairie
Prairies de graminées mixtes des Grandes Plaines

CM051 describes the Canadian expression of North American Great Plains mixedgrass prairie, including the grasslands of the dry climate of southern Alberta and Saskatchewan. The name “mixedgrass” refers to the characteristic mixture of mid-height grasses (mid-grasses) and short grasses. In Canadian mixedgrass prairie, the mid-grass component is generally dominant, but the short grass component becomes more conspicuous in the drier portions of the range. The dominant mid-grasses include needle-and-thread grass (Hesperostipa comata), northern porcupine grass (H. curtiseta), thick-spike wildrye (Elymus lanceolatus) and western wheatgrass (Pascopyrum smithii). The most important short graminoids are prairie junegrass (Koeleria macrantha), blue grama (Bouteloua gracilis) and several upland sedges (Carex spp.). Abundant forbs and dwarf shrubs are scattered throughout the grassland.

CM051 occurs in a dry continental temperate climate with cold winters and warm summers. Mean annual temperatures average approximately 3.6˚C, and precipitation varies from approximately 300 to 430 mm. CM051 stands occur on a variety of well-drained soils, including Chernozems on sandy, loamy and clayey parent materials, Solonetzic soils with a dense hardpan layer and Regosols on dune sands. Mixedgrass prairie, in its broad definition, ranges southward to northern Texas and northeastern New Mexico, but the Canadian expression is somewhat distinctive in species composition.