Overgrazing has been a contributing factor in the decline of native grasslands, but now cows are getting an opportunity to play a role in restoring healthy prairies and grasslands.
Well-managed periodic grazing is the driving idea behind a grassland management project led by cattleman Dan Jenniges, in partnership with the DNR, the U.S. Fish and Wildlife Service, The Nature Conservancy, and the Pope County Soil and Water Conservation District. The project compares five-acre plots of grasslands that are grazed, cut for hay, burned, or left idle. Plots are on federal waterfowl production areas, state wildlife management areas, Nature Conservancy land, and private lands enrolled in the federal Conservation Reserve Program in Pope and Stevens counties.
Local pastures are generally overgrazed, compacting the soil and opening the way for nonnative grasses to invade. Grasslands that are idled for too long, such as recreational hunting lands or CRP acres, are generally not as productive or healthy as grasslands with a periodic disturbance of grazing or fire. Herein lies both the problem and the opportunity.
Jenniges approached the participating agencies to organize the project in fall 2007 to examine the similarities and differences among various grassland management techniques and to determine how well-managed grazing by cattle can be a useful management tool. Grazing and haying are allowed on CRP lands, but penalties limit their practicability. Grazing is not widely used on public lands as a grassland management tool in Minnesota.
Carefully managed grazing may simulate grazing by bison, which was once an integral part of the prairie growth cycle. Fires would burn off the duff of dead grasses. Bison herds would then move in to feed on tender shoots of new grasses and forbs, and their hooves would dig up the soil -- in effect tilling the land for seeds. The next spring a prairie fire would burn another area, and the bison would go there to feed, leaving the previous year's patch behind to grow undisturbed until another fire burned.
Today, cattle grazing in combination with prescribed burning can potentially be used to mimic this historic disturbance of grasslands. Together, grazing and burning promote a high diversity of plant species. While burning tends to promote grass growth, grazing tends to increase forbs.
Grazing may also invigorate grass growth by knocking seeds off plants, mashing seeds into soil with hooves, removing dead grasses, stimulating nutrient cycling, and providing free fertilizer. By knocking back cooler-season grasses, such as nonnative brome and bluegrass, spring grazing can be a strategy for fostering warm-season grasses, such as bluestem and Indiangrass.
"These tools, if used wisely and judiciously, can direct plant succession toward our desired goal of healthy, diverse prairie ecosystems," says Jared Culbertson of The Nature Conservancy.
This grassland management project is funded largely by the Working Lands Initiative, a consortium including the DNR and other government agencies, conservation groups, and farmers and landowners.
"The core concept of Working Lands is to strike a balance between agriculture and habitat through local working groups," says Tabor Hoek, DNR Working Lands coordinator. "This project demonstrates that landowners can balance economic viability and accomplish habitat goals for wildlife."
On Aug. 20, the Pope County SWCD is conducting a public tour of the project sites. For information, call 320-634-5327.
Richard Olsen, DNR assistant area wildlife manager Glenwood