From: Fred Harris
DNR plant ecologist
Q: Herds of bison once roamed and grazed the prairie. Can cattle grazing provide similar benefits to Minnesota’s remaining prairie habitat?
A: Yes, cattle grazing can provide many benefits to prairie landscapes and wildlife. Some bird and mammal species such as prairie chickens and jackrabbits strongly benefit from the short grass habitat that grazers produce. Grazing may also increase plant diversity in some soils and allow managers to decrease the frequency of controlled burns, which benefits fire-sensitive species like pollinators.
As with any management tool, grazing can also cause problems if it is not used well. Wet to mesic soils are prone to increases of invasive species when overly disturbed by grazers. Toxic chemicals such as de-wormers can be introduced by livestock, and woody species can increase due to loss of fuel for controlled burns. Broad generalizations about the outcomes of cattle grazing don’t work very well because everything depends on management: how many animals, in how big a space, in what kind of habitat, in what kind of conditions, and for how long.
The DNR sets clear ecological goals for grazing on wildlife management areas. Those goals determine which portions get grazed, when and for how long. We don’t have all the answers yet; DNR staff participate in multi-agency meetings every year to discuss examples of grazing management, and we need monitoring data from grazed sites to help make good decisions in the future.