Cheatgrass (Bromus tectorum). Photo © Steve Dewey, Utah State University
An aggressive invasive from Russia has emerged as a significant factor in the wildfires that rolled through much of the West this past summer, and several western states have decided it’s time to get serious about eradicating the ubiquitous cheatgrass (Bromus tectorum). The governors of Idaho, Nevada, Utah and Wyoming are developing a strategy for rehabilitating thousands of acres of scorched rangeland by reseeding with native and nonnative grasses before cheatgrass can take hold.
Because it dries early in the season and then forms a thick mat that allows fire to easily spread, cheatgrass provides a wealth of tinder for lightning strikes and other fire sources. It is such a prodigious seed producer that it’s back in early spring, pushing upward through the soil and crowding out native grasses.
But replacing cheatgrass—which since the early 1900s has seeded itself throughout the West’s over-grazed rangelands—is proving to be daunting. First is the problem of finding enough native grass and sagebrush seed to replant the millions of acres charred by fire; the Associated Press estimates that reseeding 650,000 acres burned by this summer’s Murphy Fire in Idaho and Nevada will take 1.4 million pounds of seed. Then there is controversy over what types of grasses or vegetation would best replace, and outpace, the quickly regenerating cheatgrass.
In Utah, the Bureau of Land Management is reseeding 120,000 acres burned in July’s Milford Flat fire, Utah’s largest fire on record. Jack Brown, BLM’s emergency stabilization and rehabilitation coordinator for Utah, says the agency will be reseeding with a mixture of native and nonnative grasses, as well as with forage kochia, a nonnative, fire-resistant shrub that has proven effective in warding off fires. Forage kochia (not to be confused with annual kochia, an invasive weed that animals don’t find palatable) is a perennial that stays green much of the season and provides year-round forage for livestock and wildlife.
Brown says an open area burned by fire in 1980 was reseeded with kochia and various grasses to hold down the soil. Twenty years later, the dominant vegetation in the area is kochia, and although the Milford fire burned a short distance into the area this summer, “then it went out,” he says. “The fire went around it.”
In reseeding efforts, Utah and the other western states rely on crested wheatgrass, a nonnative grass from Siberia, saying that native grasses don’t compete well with cheatgrass. Some environmentalists charge that crested wheatgrass is used because it provides forage for livestock, and are pushing for reseeding with native grasses instead.
Even though it qualifies as a nonnative, that’s another advantage of reseeding with kochia, Brown says. Once a salt desert shrub habitat burns, it’s hard to get it to come back, he says. “Kochia fills a niche, allowing other natives a foothold and crowding out the cheatgrass.”