Located in an ancient outwash channel of the Crow River, Roscoe Prairie sits on the eastern edge of what once was an unbroken expanse of prairie. Its surroundings contained wetlands that were once drained for farming. Today the tract is surrounded by previously cultivated agricultural fields, hay meadows, and pastures. Visitors can enjoy birds, flowers, and butterflies on this prairie preserve.
Why the Conservancy Selected This Site
Roscoe Prairie was preserved because it once was a breeding ground for the Dakota Skipper butterfly, a species threatened in Minnesota. This insect is very rare in North America and is restricted to tallgrass prairie remnants. In 1966, a specimen was collected from Roscoe Prairie, which contains relatively undisturbed native prairie.
What the Conservancy Has Done/Is Doing
The primary threats to the biodiversity at Roscoe Prairie are the introduction of non-native species and the suppression of fire. Except for areas where plowing once occurred, signs of past disturbances are now disappearing. The Nature Conservancy manages the preserve through prescribed burning; monitoring plants, birds, mammals and butterflies; conducting biological inventories and controlling non-native species such as leafy spurge, sweet clover, and Canadian thistle. There is also a recurring threat of woody invasion by willow and aspen in the wet prairie areas, a problem that is addressed by burning and girdling the aspen.