Below the canyon slopes and extending to the creek are a wide variety of soils and a great diversity of plants. Most of the plants of the plains and escarpment are found here. Some of the soils of the nearly level areas are deep, high in fertility, and hold large amounts of water. Tall grasses, such as indiangrass and switchgrass, occur admixed with mid grasses; a rank growth of vine-mesquite grass often occurs in the areas where runoff water collects; and alkali sacaton grass grows on saline soils. Other trees and shrubs include hackberry, soapberry, wafer ash, button bush, foresteria, and Texas buckthorn. Along the creek, cottonwoods, willows, and salt cedar are common.
Because of the varied topography, diversity of plant life, and geographical locations, the canyon affords an ideal habitat for wildlife. Some of the mammals that occur here are the coyote, porcupine, jackrabbit, cottontail rabbit, raccoon, opossum, ringtailed cat, striped skunk, gray fox, white-footed mouse, woodrat, and bat. Mammals that were once common but are now absent or extremely rare are the bison, black bear, black-footed ferret, lobo wolf, cougar, and bobcat. The moose and American elk were introduced into the canyon but are no longer to be found. White-tailed deer, mule deer, and aoudad sheep have also been introduced and are still present. The mule deer is the most common. A great many types of birds are found either as residents of or migrants to the canyon. A few are the golden eagle, red-tailed hawk, sparrow hawk, Mississippi kite, turkey vulture, blue quail, killdeer, nighthawk, roadrunner, red-headed woodpecker, golden-fronted woodpecker, canyon wren, mockingbird, robin, cardinal, meadowlark, Bullock’s oriole, painted bunting, white-crowned sparrow, and lark sparrow.
Archeological studies indicate that the earliest known inhabitants of Palo Duro Canyon lived in the canyon from about 10,000 to 5,000 B.C. These early men hunted bison and now-extinct elephant-like mammoths that roamed the area during the Pleistocene Ice Age. Their stone weapons and artifacts have been found in the canyon. Presumably these primitive people, like those who came later, were attracted by streams and springs in the canyon, and by game that came to feed there. Rock exposed in the canyon provided material for tools and weapons.