In arid and semi-arid environments, introduced invasive plants fill openings left by fires. In the Great Plains, perennial grasses tolerate fires well. Where livestock grazing and other disturbances have broken soil surfaces, however, the fire increases the opportunities for invasive plants to establish. Fine fuel builds up. Shortened fire recurrence intervals can overcome the resistance of perennial grasses and lead to weedlands of little value for wildlife, wildlife, or soil stability.