The ability of cheatgrass to rapidly spread and fill in the ground between other plant species may be one reason the plant is involved in larger and more frequent blazes, said Balch, who worked with Bethany Bradley, assistant professor of environmental conservation, University of Massachusetts-Amherst; Carla
D'Antonio, professor of ecology, evolution and marine biology, University of California-Santa Barbara, and Jos Gmez-Dans, research associate in the department of geography and the National Centre for Earth Observation, University College London.
Balch said the cheatgrass-influenced fires create a difficult management challenge. The fires can threaten agricultural lands and, since more people are building homes in the west, residential areas as well as habitat for threatened native wildlife, such as the greater sage grouse.
While cheatgrass-driven fires have been recognized for decades, remote sensing technology has allowed the researchers to take a regional approach to assessing the problem. They compared burned area detected by NASA's Moderate Resolution Imaging Spectroradiometer between 2000 to 2009 to regional land cover maps that included cover of cheatgrass.
"Historically, the way remote sensing worked, you could only tell the difference between broad land cover classes such as trees versus wetlands, for instance," Bradley said. "It is very difficult to capture those details at the species level."
However, by noticing what conditions favor the growth of certain species, the researchers were able to use the satellite imagery to better pinpoint the growth of different species. For instance, cheatgrass grows during wet periods while many other species do not, Bradley said.
"What you end up seeing is that most years when it is dry, the cheatgrass doesn't grow much," said Bradley. "But when there are wet season
|Contact: Matthew Swayne|