Biologists in the Dillon Field Office recently mowed sagebrush in some important sage grouse and antelope habitat in far southwestern Montana.
What?! BLM is mowing sagebrush, even given all the concern about preserving this kind of habitat?
That’s right! It may be an unorthodox practice, but it may have been the only way to actually restore a healthy sagebrush community in some vital wildlife habitat.
Jim Roscoe and Kelly Bockting have been monitoring sagebrush in Big Sheep Creek Basin southwest of Dillon for several years. Data extending back through 1983 indicated a continuing decline in healthy sagebrush. As much as 85 percent of the plants were decadent and the average plant height had decreased by 30 percent, making much of it unavailable as winter forage and cover during even light snow conditions. This area is winter survival habitat for up to 350 antelope and is within a half mile of a sage grouse lek.
The Big Sheep watershed planning process concluded that it was time to do something about this problem, and authorized treatments to restore up to 400 acres of sagebrush. Here’s what raised people’s eyebrows: in contrast to past projects that focused on reducing or eliminating sagebrush, this one aimed to stimulate greater production from the existing sagebrush community.
Roscoe and Range Conservation Specialist Brian Hockett decided that mowing might be the best option. Based on experience and observations of similar efforts on private lands in the area, they believed that mowing could stimulate sagebrush growth and production in as little as 5-10 years while protecting current wildlife uses to the greatest extent possible.
With this as the goal, Roscoe and Bockting rented an agricultural tractor and 15-foot mower from a local implement dealer and headed into the frigid solitude of Big Sheep Basin. After two weeks of working through equipment breakdowns and temperatures occasionally hovering at sub-zero levels, about 200 acres of sagebrush had been mown. Part of the area was reseeded with a sagebrush/yarrow/Lewis flax mix to evaluate the need for and effectiveness of reseeding.
The timing of mowing, the size and shape of the treated areas, light snow cover, natural seed production, and the availability of new seed should all combine to restore sagebrush cover and productivity. Coordinated livestock management and potential antelope harvest changes will further enhance the success of the project. Now all that remains is to hope for plentiful winter snows and spring rains to replenish sagebrush on this important wildlife habitat.