This mid-boreal ecoregion occurs as 10 separate, mostly upland areas, south of the Canadian Shield (147), stretching from north-central Alberta to southwestern Manitoba. It includes remnants of the Alberta Plateau (139, 140, 141, 144) in Alberta, several prominent uplands known locally as the Thickwood (150), Pasquia (151), and Porcupine (152) hills in Saskatchewan, and the Duck (153) and Riding (154) mountains in Manitoba. The climate has predominantly short, cool summers and cold winters. The mean annual temperature ranges from -1°C to 1°C. The mean summer temperature ranges from 13°C to 15.5°C and the mean winter temperature ranges from -13.5°C to -16°C. Some areas of the ecoregion can be very cold with winter mean temperatures exceeding -17°C in northern Alberta. The mean annual precipitation ranges 400-550 mm. The ecoregion is classified as having a predominantly subhumid mid-boreal ecoclimate. These uplands form part of the continuous mid-boreal mixed coniferous and deciduous forest extending from northwestern Ontario to the foothills of the Rocky Mountains. Medium to tall, closed stands of trembling aspen and balsam poplar with white and black spruce, and balsam fir occurring in late successional stages, are most abundant. Deciduous stands have a diverse understory of shrubs and herbs; coniferous stands tend to promote feathermoss. Cold and poorly drained fens and bogs are covered with tamarack and black spruce. Consisting for the most part of Cretaceous shales, these uplands are covered entirely by kettled to dissected, deep, loamy to clayey-textured glacial till, lacustrine deposits, and inclusions of coarse, fluvioglacial deposits. Elevations range from about 400 to over 800 m asl. Associated with rougher morainal deposits are a large number of small lakes, ponds, and sloughs occupying shallow depressions. Permafrost is very rare and found only in peatlands. Well-drained Gray Luvisolic soils are dominant in the region. Significant inclusions are peaty-phase Gleysols and Mesisols that occupy poorly drained depressions. Dystric Brunisols occur on droughty, sandy sites. In Alberta, the ecoregion slopes gently and drains northward via the Athabasca and Clearwater rivers and their tributaries, whereas in most of Saskatchewan and Manitoba the uplands slope gently and drain northeastward via the Churchill and North Saskatchewan river systems. Characteristic wildlife includes moose, white-tailed deer, elk, black bear, timber wolf, lynx, snowshoe hare, beaver, and muskrat. Bird species include common loon, red-tailed hawk and neotropical migrants. Pulpwood and local sawlog forestry, water-oriented recreation, hunting, and trapping are the main land use activities. Agricultural activities are significant in southern parts of the ecoregion, particularly in Saskatchewan and Manitoba. Major communities include Fort Assiniboine, Trout Lake, Peerless Lake, La Loche, Buffalo Narrows, and Île-à-la Crosse. The population of the ecoregion is approximately 45 200.
This ecoregion is part of the Boreal Plains ecozone.