Groves of deciduous trees nestled among fields of prairie grasses and flowers create an intricate quilt of prairie and woodland known as the tallgrass aspen parkland. This northwestern Minnesota biome, home to a rich diversity of animal and plant life, exists in a natural transition between the dry, windy prairies to the west and the moist, cold coniferous forests to the east. Although the smallest biome on the Minnesota map, the tallgrass aspen parkland expands across three provinces in Canada. Ten thousand years ago Glacial Lake Agassiz receded, leaving behind large, flat plains. In the early 19th century, farmers’ high hopes for this area were dashed as rocky, wet, and poorly drained soil produced small yields and crop farming gave way to cattle grazing. Today, this open landscape provides a great opportunity to view sandhill cranes, elk, bear, and a horizon dotted with farms, aspen groves, and fields of big bluestem.
What is a tallgrass aspen parkland?
The tallgrass aspen parkland is a mosaic of prairie and sedge fens (wetlands fed by ground water) accented by groves of aspens or scattered bur oaks. It is a place where plants and animals well adjusted to harsh winds, extreme temperatures, and dry conditions thrive. This appropriately named “parkland” seems designed to please the human eye—as if nature has placed trees and prairie patches to enhance their individual beauty and the overall grandeur of the landscape.
Evapotranspiration is greater than precipitation across this biome in Minnesota. That means more water evaporates from the ground and transpires from plants than falls from annual rain and snow!
Foundations of today’s tallgrass aspen parkland
Glacial Lake Agassiz once stretched across this biome. It left behind a rocky, flat plain open to nature’s elements. Storms, strong winds, and fire molded the land into a mix of deciduous trees, prairie grasses, and wildflowers that thrive under the challenging climate and soil conditions of the area.
Climate is key
Life is tough in the tallgrass aspen parkland. Uninterrupted by hills, strong dry winds blow from the western prairie and yield very little precipitation. Cold winters and hot summers are typical.
Trees versus prairie
As tranquil as the tallgrass aspen parkland appears, it is a battleground between trees and grass. Aspen seek to advance across grasslands and convert the entire land into forest. Fires beat the aspen back and open up spaces for prairie grasses to flourish. Centuries ago, wildfire worked the landscape alone. Today, natural resource managers set prescribed burns to maintain this biome’s unique plant composition.