Alberta's soil scientists formed a Soil Classification Working Group in 1998. They organized information on the Canadian province's different soil types according to soil properties. Establishing 10 distinctive soil types within four larger soil categories, they created a map of the different soils across Alberta to help farmers and gardeners evaluate their own soil before planting. One soil type, vertisols, exists only in a small area of southern Alberta's Drumheller Valley.
Alberta's chernozemic soils are prevalent through its grasslands. Each of the four kinds of chernozemic soils is contains a different amount of organic material and moisture. Brown chernozemic soil is the driest, with 3 to 4 percent organic material in its 4-to-6-inch brown surface layer. Slightly moister is dark brown chernozemic soil, at 4 to 6 percent organic matter in about 5 to 6-1/2 inches of surface.
The two chernozemic soils highest in moisture are black and dark gray, both with from 5 to 8 inches of surface soil and 6 to 10 percent organic matter. Dark gray soil predominates in areas where the grasslands yield to forests. Those spots usually have shorter growing seasons than areas with black soil. Dark gray chernozemics combined with create to dark gray luvisols create a fifth soil type in Alberta's Peace River Parklands.
Luvisolic soils develop in the cool conditions of Alberta's western foothills' natural forests. They are the result of organic forest vegetation accumulating more quickly than it breaks down. The organic layer, not far above the water table, ranges from 16 inches to more than 5-feet thick. Clearing the forests for cultivation mixes the organic matter into the soil, accounting for its deep gray color. Luvisolics account for three other soil types when they encounter the organic or cryosolic soils of northern Alberta or the brunisols of the Rockies.
Brunisolic soils prevail at Alberta's well-drained higher elevations along the Rocky Mountains' eastern slope, and in the province's northeastern corner. Their dark brown or black organic surface layers vary from less than 1 to more than 8 inches. Because they're in areas with short growing seasons, brunisolic soils are largely uncultivated.
Cryosolic soils, found mainly in the subarctic regions of northwestern and north central Alberta, are permanently frozen less than 3 feet from their surface, says Alberta Heritage. They are unsuitable for cultivation.
Vertisolic soils, according to the University of Idaho, have high concentrations of clay. They retain moisture and swell during wet weather, and shrink to the point of cracking in drought. They account for less than 2-4/10 percent of global soils.