The term Cross Timbers, also known as Ecoregion 29, Central Oklahoma/Texas Plains, is used to describe a strip of land in the United States that runs from southeastern Kansas across Central Oklahoma to Central Texas. Made up of a mix of prairie, savanna, and woodland, it forms part of the boundary between the more heavily forested eastern country and the almost treeless Great Plains, and also marks the western habitat limit of many mammals and insects.

Central Oklahoma is the geographical name for the central region of the U.S. state of Oklahoma. It is also known by the Oklahoma Department of Tourism designation, Frontier Country, defined as the 12-county region including Canadian, Grady, Logan, Oklahoma, Cleveland, McClain, Payne, Lincoln, Pottawatomie, Seminole, Okfuskee, and Hughes counties.