An extensive temperate grassland with flat or rolling terrain and moderate to low precipitation. The term is most often applied to North American grasslands, which once extended from Alberta to Texas and from Illinois to Colorado, but similar grasslands exist around the world. Perennial bunchgrasses and forbes dominate prairie flora. In dry climate prairies, a lack of precipitation prohibits tree growth except in isolated patches, such as along stream banks. In wetter prairies, periodic fires are essential in preventing the incursion of trees and preserving open grasslands. Historically, huge herds of large mammals and scores of bird, rodent, and insect species composed native prairie fauna. During the nineteenth and twentieth centuries most of North America's native prairie habitat and its occupants disappeared in the face of agricultural settlement, cattle grazing, and fire suppression. Today the geographic extent of native prairie plants and animals is severely restricted, but pockets...