The geographical center of the county lies two miles northwest of downtown Austin at 30°18' north latitude and 97°45' west longitude. Travis County comprises 989 square miles on the eastern edge of the Edwards Plateau and is divided by the Balcones Escarpement. The land west of the escarpment is more arid than that to the east, and the vegetation varies accordingly, ranging from juniper, Mesquite,  and scrub brush to oak, cottonwood, redbud, and pecan trees. Elevations in Travis County range from 400 to 1,300 feet above sea level. Between 21 and 30 percent of the land is considered prime farmland. The Colorado River, which bisects the county from northwest to southeast, flows from the Hill Country. Onto the Coastal Plain and provides drainage for the entire area. Wildlife in the area includes deer, coyote, bobcat, squirrel, beaver, opossum, ring-tailed cat, badger, fox, raccoon, and skunk, as well as a variety of birds, fish, and reptiles. Among the county's mineral resources are dolomite, limestone, industrial sand, gravel, oil, and gas. The climate is subtropical, with an average low temperature in January of 38° F and an average high in July of 96°. The average yearly rainfall is thirty-two inches, and the growing season is 270 days.