More than 2,500 plant species have been found in Ohio. The southeastern hill and valley region supports pitch pine, bigleaf magnolia, and sourwood, with undergrowths of sassafras, witch-hazel, pawpaw, hornbeam, and various dogwoods. One can find at least 14 species of oak, 10 species of maple, 9 of poplar and pine, 7 of ash and elm, 6 of hickory, 5 of birch, and 2 of beech along with butternut, eastern black walnut, wild black cherry, black locust, and sycamore. A relative of the horse chestnut (introduced to Ohio from Asia), the distinctive buckeye—first called the Ohio buckeye and now the official state tree—is distinguished by its clusters of cream-colored flowers that bloom in spring and later form large, brown, thick-hulled nuts. Five Ohio plant species were listed as threatened in 2003, which included eastern prairie fringed orchid, northern wild monkshood, and lakeside daisy.
In Ohio’s five wildlife districts you can find white-tailed deer beaver,, badger, raccoon, mink, red and gray foxes, coyote, woodchuck, eastern cottontail, least shrew, and opossum. The bobcat, woodland jumping mouse, and red-backed mole are among many species with more restricted habitats. Common birds include the eastern great blue heron, mourning dove, green-winged teal, eastern belted kingfisher, blue-gray gnatcatcher, eastern cowbird, and a great variety of ducks, eastern horned lark, woodpeckers, and warblers. The cardinal is the state bird, and the ruffed grouse, mostly confined to the Allegheny Plateau, is a favorite game species.
The US Fish and Wildlife Service listed 20 Ohio animal species as threatened or endangered in 2003, including the bald eagle, Indiana bat, Scioto madtom, and piping plover.