Features

“[A grassland] is hundreds, literally hundreds, of species of plants woven together in a complex fabric of interdependencies that extend then to insects, to birds, to a carpet of rodents, to predators, and finally to large mammals, of which humans are but one... A wheat field is nothing more than a clearcut of the grass forest.”

   – Richard Manning, Grassland, 1995

Just as a forest is more than trees, a grassland is more than grass. But to best appreciate the biodiversity of the grasslands, one must settle in just before sunset and let the creatures go about their business undisturbed. Look up and watch the nighthawks diving for insects, accompanied by that inimitable two-toned hum of the wind across their wings. Enjoy the pronghorn’s proud silhouette on the horizon. Listen to the coyote howls and the wind whispering in the grasses. And watch the deer come down to drink from the precious streams and wetlands scattered throughout this semi-arid region.

Alberta’s Grassland Natural Region, comprising four natural subregions, covers about 14 percent of Alberta, or about 95,500 km2. About 18 percent of the region is covered with permanent and temporary wetlands, and only 1 to 2 percent is occupied by water in major rivers and shallow lakes. Of what was once native, unploughed prairie in Alberta, only about 43 percent remains, and of the entire Grassland Natural Region, less than 1 percent is protected.

Native grasses near Coronation

Topography

Grasslands are not as flat as is often thought. Much of the Grasslands Natural Region comprises undulating plains. Hummocky terrain is found in the northern portions, rolling hills in the west, and badlands and exposed bedrock along river valleys. Elevation ranges from 800 m (Dry Mixedgrass Subregion) to 1,525 m (Foothills Fescue Subregion).

Habitat Types

Alberta’s grasslands contain grass-covered uplands, lush river valleys, permanent marshes, temporary wetlands, shallow lakes, and sand dunes and plains. This combination of diverse habitats supports a wide diversity of life, each species adapted to its own specialized niche.

Cliff Swallow nests along the Milk River - credit: H. Unger

Wildlife

The Grasslands Natural Region is known for its high concentration of species listed as Special Concern, Threatened, Extirpated, or Endangered by Canada’s Species at Risk Act. (See a current list.) The October 2008 joint federal-provincial hearing for EnCana’s proposed infill project in the Suffield National Wildlife Area brought attention to several of those species, including the Ord’s kangaroo rat, the Sprague’s pipit, and three endangered prairie plants.

Alberta’s grasslands contain many animal species found nowhere else in Alberta, including swift fox, great plains toad, several species of tiger beetle, yucca moth, and mountain plover. The dunes near Blindloss are home for the most northerly population of Ord’s kangaroo rat. Living at the edge of its habitat makes this species particularly vulnerable.

Ferruginous Hawk, Suffield National Wildlife Area - credit: N. Douglas

Plants

About 25 percent of Alberta’s rare vascular plant species occur in the Grasslands Region, and about 55 rare species occur in Alberta only in the grasslands. Trees and shrubs grow only along rivers and streams, and in terrain that is protected from the dessicating winds and hot summer sun.

As one moves north and west from the semi-arid, largely native prairie of southeastern Alberta, moisture increases and the land merges with extensively cultivated prairie areas – most of the native biodiversity has been lost in these areas.

• “Mixedgrass” refers to the mixture of short and mid-height grasses. The most widespread grasses in this subregion are blue grama, needle-and-thread, June grass, and western wheat grass. In spring and summer, many species of wildflowers are sprinkled among the grasses.
• Shrubs include silver sagebrush, silverberry (also known as wolf willow), buckbrush, and prickly rose.
• Along river valleys, tall forest and shrub communities thrive, including plains cottonwood, willow, and thorny buffaloberry.
  
  

• Climate is similar to the Dry Mixedgrass Subregion, with slightly cooler and moister conditions.
• Dry, sandy sites contain needle-and-thread grass, northern wheatgrass, sand grass, and June grass. On moister soils, blue grama grass, needle grasses and northern wheat grass thrive.
• Species on the slopes of the Cypress Hills include plains rough fescue, western porcupine grass, and sedges.
• Ravines, coulees, and other sheltered areas provide habitat for shrubs, including buckbrush, silver sagebrush, silverberry, and prickly rose.
• Tree species include plains and narrowleaf cottonwood and balsam poplar along the Oldman River, and balsam poplar in the Cypress Hills.
  
  

• Vegetation is transitional between prairie and parkland, showing characteristics of both regions
• Dominated by plains rough fescue, Alberta’s provincial grass
• Grasses on the driest sites include blue grama, northern wheat grass, sand grass, and June grass. Moister sites contain western porcupine grass, plains rough fescue, northern wheatgrass, and porcupine grass.
• Other plant species include balsam poplar, aspen, plains cottonwood, willow, sedge, bulrush, and common cattail.
  
  

• This subregion is characterized by cooler summers, a shorter growing season, warmer winters, and more precipitation than the other three subregions.
• Herbaceous plants are diverse, including species not common in other subregions, such as sticky purple geranium and silvery perennial lupine.
• The prevalence of mountain rough fescue, Parry oat grass, and bluebunch fescue distinguish this subregion from the others.

Sage bush, Middle Sand Hills - credit: A. Teucher

Land Use

Agriculture is the principal land use in the Dry Mixedgrass Subregion, with grazing occurring over about 55 percent of the area and dryland farming (crops, fallow) taking up about 35 percent. Nearly 10 percent is under irrigation, and oil and gas activity is extensive throughout the region.

The Mixedgrass Subregion is the most intensively cultivated subregion in Alberta – 85 percent of the region is planted to annual crops. About 5 percent of the subregion is under irrigation. Oil and gas development is common throughout this area.

In the Northern Fescue and Foothills Fescue Subregions, agriculture is the primary use of the area, including both annual cultivation and grazing. Other uses include significant oil and gas activity, mining, and outdoor recreation, including motorized vehicle use.

Pakowki Lake dunes - credit: C. Wershler

“There are people who think of the prairie as boring, and it’s hard not to pity them.”

   – Candace Savage, Prairie: A Natural History