|Shape and Distribution
Southern red oak is also referred to as Spanish oak. It is a large tree, up to 80 feet tall, with a trunk diameter of up to 4 feet. The crown is rounded and open, with spreading branches. It usually grows on well drained or dry, poor upland soils in southern mesic forests in Illinois. It also occurs occasionally in bottomlands in the state. Its range extends along the east coast from central New Jersey south to central Florida, west to eastern Texas and back east across central Missouri and south-central Illinois, through Indiana, Kentucky, and Tennessee.
Cherrybark oak (Quercus pagoda) is often treated as a variety of southern red oak. Whereas there are general morphological differences between the two, some of the characteristics that separate them can be variable. Spanish oak leaves, for example are usually 3 to 5 lobed, whereas cherrybark oak leaves usually have 5 to 11 lobes, but this characteristic is variable, with some southern red oak leaves having 5 or more lobes. Southern red oak leaves are more noticeably hairy below. Southern red oak bark is furrowed whereas the cherrybark oak bark is furrowed, but also broken into scales that give it the appearance of black cherry bark.
The two species have different habitat preferences. Cherrybark oak prefers poorly drained bottomland sites and mesic slopes in extreme the southern part of the state. Southern red oak prefers drier, poor upland soil, and is also present in the southern part of the state.