Alberta's Foothills Natural Region
Updated December 15, 2006
The Foothills Natural Region is influenced by a moist, cool climate. Gently undulating to rolling till-covered hills and plateaus with deciduous and mixedwood forests are typical of lower elevations, and strongly rolling to steeply sloping hills with coniferous forests are prevalent at higher elevations.
The Foothills Natural Region includes the
Lower and Upper Foothills Natural
Subregions. The Region extends along the
eastern flank of the Rocky Mountains north
from the Bow River Valley to just south of
Grande Prairie. It also includes the Swan Hills
and Pelican Mountain outliers to the east and
the Saddle Hills outlier north of Grande
The topography is highly variable, ranging from sharp, bedrock-controlled ridges near the mountains to rolling and undulating terrain in the north and east. Elevations within the Foothills Natural Region range from a low of 700 m in the most northerly areas to a maximum of about 1700 m in the south.
Mixed forests of aspen, lodgepole pine, white spruce and balsam poplar with variable understories on Gray Luvisolic soils are dominant on average sites at lower elevations. Lodgepole pine forests with less diverse understories and well developed feathermoss layers on Brunisolic Gray Luvisols are typical of higher elevations.
The following links provides basic information on the key characteristics at the subregion level.
- Lower Foothills Natural Subregion
The Lower Foothills Natural Subregion represents a climatic transition area, with cold winters typical of Boreal climates and higher winter snowfalls typical of Cordilleran climates. The rolling, till-covered plateaus are forested by mesic, closed canopy mixed stands of aspen, lodgepole pine, white spruce and balsam poplar.
- Lodgepole pine occurs in pure or mixed stands on mesic sites, differentiating this Natural Subregion from the Boreal Forest Natural Region to the east and north.
- The occurrence of pure deciduous stands on all aspects distinguishes this Natural Subregion from the Upper Foothills Natural Subregion, where pure deciduous stands are typically restricted to southerly aspects.
The Lower Foothills Natural Subregion occupies a broad northwest-to-southeast belt between the Bow River Valley to the south and Grande Prairie to the north, with outliers in the Swan Hills and Pelican Mountains to the east, and the Saddle Hills to the north.
It occurs at lower elevations in the Region, ranging from about 700-800 m in the north and east along its boundary with the Dry and Central Mixedwood Natural Subregions, to over 1500 m in the south and west along its boundary with the Upper Foothills Natural Subregion. Its upper boundary with the Upper Foothills Natural Subregion decreases with latitude at a rate of about 1.2 m per kilometer northward; its lower boundary with the Central and Dry Mixedwood Natural Subregions decreases with latitude at a rate of about 1 m per kilometer northward.
Lower Foothills climate, soils and vegetation patterns indicate a transition between cold, dry continental climates and milder, moister Cordilleran climates. Continental influences are more pronounced in the Lower Foothills than in the Upper Foothills. This is most clearly reflected by a decrease in both annual and winter precipitation and an increase in growing degree-days. The Lower Foothills Natural Subregion occurs mainly at the westernmost extent of the Interior Plains, and rolling and undulating till-covered landscapes are typical.
- Upper Foothills Natural Subregion
Short, wet summers and snowy, cold winters influence the Upper Foothills Natural Subregion. Closedcanopy conifer stands of lodgepole pine, black spruce and white spruce on rolling to steeply sloping terrain are typical.
- Lodgepole pine is usually dominant in pure stands on mesic sites, with white spruce and white-spruce-Engelmann spruce hybrids at higher elevations along the boundary with the Subalpine Natural Subregion.
- Subalpine indicators are restricted to northerly aspects at the highest elevations (e.g., whiteflowered rhododendron).
- Pure deciduous stands are generally restricted to southerly aspects, and mixed conifer- deciduous stands are much less common in the Upper than in the Lower Foothills.
The Upper Foothills Natural Subregion includes about 34 percent of the Foothills Natural Region area. It occupies a narrow belt between the Lower Foothills Natural Subregion at lower elevations and the Subalpine Natural Subregion at higher elevations, with one outlier on the highest elevations of the Swan Hills.
Elevations range from about 1050 m in the north to more than 1700 m in the south and west along its boundary with the Subalpine Natural Subregion. Its lower boundary with the Lower Foothills Natural Subregion decreases with latitude at a rate of about 1.2 m per kilometer northward. Its upper boundary with the Subalpine Natural Subregion decreases at a rate of about 0.6 m per kilometer northward.
Upper Foothills Natural Subregion climate, soils and vegetation patterns indicate a transition between the drier, somewhat warmer conditions of the Lower Foothills Natural Subregion and the cooler, wetter conditions of the Subalpine Natural Subregion. The Upper Foothills Natural Subregion occurs mainly within the high-elevation dissected plateaus and foothills of the Rockies Front Ranges. Strongly rolling to steep terrain with thin glacial deposits and exposed bedrock is typical.
The new Natural Regions and Subregions of Alberta Report (5.2 MB) is now available.
View the Errata Report(23 KB) for the printed and digital versions of the above report, prior to May 15 2006.