An invasive grass species may be one reason fires are bigger and more frequent in certain regions of the western United States, according to a team of researchers. Researchers used satellite imagery to identify cheatgrass, a plant species accidentally introduced by settlers in the West during the 1800s, in a disproportionately high number of fires in the Great Basin, a 600,000 square-kilometer arid area in the West that includes large sections of Nevada, as well as parts of Utah, Colorado, Idaho, California and Oregon.