By some regarded as a subdivision of the Boreal Forest, this is a large area extending from the Manitoba lowland to the Rocky Mountains, including most of the commercial forests of the Prairie Provinces. White spruce is well developed in this area but aspen, Balm of Gilead and white birch are much more common than in the main Boreal forest belt.
Aspen Grove or Parkland Region
This formation occupies a narrow zone between the open grassland and the mixed wood region. The landscape is dotted with "bluffs" or clumps of trees and the river valleys contain fairly continuous bands of forest. Aspen and black poplar are the common trees but, in the southeast, Manitoba maple (Acer negundo), bur oak (Quercus macrocarpa), elm (Ulmus americana) and green ash (Fraxinus campestris) may be found. Highbush cranberry (Viburnum trilobum) and Saskatoon berry (Amelanchier alnifolia) are common also. The tall prairie grasses of this belt include awned wheat grass (Agropyron subsecundum), slender wheat grass (A. pauciflorum), northern wheat grass (A. dasystachyum), fringed Brome grass (Bromus ciliatus), reedgrass (Calamagrostis canadensis) and Hooker's oatgrass (Avena Hookerii).
The Prairie Region
The Prairies may be divided into a short grass zone and a mixed grass zone. These belts are climatically controlled by the available water supply. In southwestern Saskatchewan and southeastern Alberta, the driest section, the common grasses are: blue grama grass (Bouteloua gracilis), common spear grass (Stipa comata), western wheat grass (Agropyron smithii), June grass (Koeleria cristata) and blue grass (Poa secunda). Other common plants adapted to the dry habitat are: pasture sage (Artemisia frigida), hoary sage (A. cana), silver sage (Eurotia lanata) and pricklypear cactus (Opuntia polyacantha). Especially noteworthy are the saline sloughs and lakes around which salt tolerant plants are found such as spike grass (Distichlis spicata), salt grass (D. stricta), alkali grass (Puccinellia Nuttalliana), barley grass, (Hordeum jubatum), sea crowfoot (Ranunculus cymbalaria), seablight (Suaeda erecta) and samphire (Salicornia rubra).
In the mixed grass zone many of the same plants appear, as well as porcupine grass (Stipa spartea), green spear grass (S. viridula), rough rescue (Festuca scabrella) and, toward the moister margin, northern wheatgrass and others which are found in the parkland zone.