Scientists study biomass haying effects on pheasants

By Ryan C. Christiansen
Web exclusive posted Nov. 7, 2008 at 10:20 a.m. CST

South Dakota State University researchers have begun a study to determine when and how much perennial grass could be harvested for the production of cellulosic ethanol without affecting the nesting success of pheasants and breeding waterfowl.

The SDSU researchers are working with the South Dakota Game, Fish and Parks Department, the U.S. Fish and Wildlife Service, and landowners to determine which combination of stubble height and haying season is best for the harvest of biomass for cellulosic ethanol production and wildlife conservation.

More than 1,400 acres of land will be studied, including private lands in the federal Conservation Reserve Program, state game production areas, and federal waterfowl production areas in the eastern South Dakota counties of Beadle, Bon Homme, Brookings, Hutchinson, Kingsbury, Lake, Moody, Turner and Yankton.

Plots approximately 40 acres in size will be hayed down to four- or 12-inch stubble lengths in either the spring or the fall and some plots will be left alone as control plots, according to Susan Rupp, a researcher in the Northern Plains Biostress Laboratory in the Department of Wildlife and Fisheries Sciences at SDSU. The plots include heavy stands of switchgrass, as well as Indian grass and big bluestem, she said.

Researchers are currently sampling the vegetation in the plots to establish a baseline for biomass production in those areas. "We're hoping to hay the fall treatments within the next few weeks before the snow really hits," Rupp said. The researchers will measure waterfowl and pheasant production in the plots after spring haying and during the breeding season in May, June, and July, she said. The study, which is scheduled for three years, will end in 2010.

Fall haying might have more impact on pheasants, Rupp said, because the harvest will remove winter cover for the birds. Some studies show that spring haying might be better for harvesting grasses for biomass for energy purposes, anyway, she added. Spring haying will be completed as close to April 1 as possible, before the breeding season.

"I think we will start getting some pretty clear indications after this next breeding season," she said. "It's going to become pretty clear whether we're seeing detrimental impacts on breeding activity in the various treatments."

The study is funded in part through a 2007 Budweiser Renewable Energy and Wildlife Conservation Research Prize from the National Fish & Wildlife Foundation.