Red oak (Quercus rubra) and white oak (Quercus alba) are both tall trees suited for large landscape spaces. White oak matures at 75 feet and red oak at 80 feet. Under ideal conditions, both oaks can reach 100 feet tall. White oak has a wider spread, up to 100 feet wide. Red oak only spreads to 75 feet. Red and white oak are in the same oak (Quercus) genus but their bark, nut, growth rate and leaf characteristics are slightly different.
The leaves of red oak and white oak are similar in length, around 8.5 inches. White oak leaves are narrower at about 4 inches, while red oak leaves are 4 to 6 inches wide. Both red and white oak leaves have lobes. White oak lobes are rounded. Red oak lobes are pointed. White oak leaves become rich red to wine-colored in the fall, while red oak leaves turn a bright red.
White oaks have a slow-to-medium growth rate during the first 20 to 30 years. After that, white oaks grow very slowly. White oaks are also difficult to transplant. Red oak grows at a rate of 2 feet per year. Red oak can grow faster under ideal conditions.
The bark on a mature white oak tree is light gray. Red oak bark is dark brown to nearly black.
Both red and white oaks produce nuts, referred to as acorns. Acorns are produced either singularly or in pairs on both red and white oaks. White oak acorns have bumpy caps, while red oak acorn caps feature smooth overlapping scales, and are wide and rounded.