AgEBB-MU CAFNR Extension
Green Horizons
Volume 21, Number 2
Spring 2017
Species Spotlight
White Oak
By Hank Stelzer | MU Extension - School of Natural Resources
White oak (Quercus alba) is one of the preeminent hardwoods of eastern and central North America. It can be found from Minnesota, Ontario, Quebec, and Nova Scotia south as far as northern Florida and eastern Texas.
Q. alba typically reaches heights of 80 to 100 feet at maturity, and its canopy can become quite massive if growing in a wide-open space, such as a field.
White oak may live 200 to 300 years, with some even older specimens known. Estimated at over 600 years old, the Great White Oak in Basking Ridge, New Jersey, was claimed to be the oldest in the United States. It measured 16 feet in circumference four feet above the ground, was 75 feet tall, and its branches spread over 125 feet from tip to tip. Unfortunately, it had been in decline for a number of years and was taken down this past winter.
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Images of leaf, winter bud, acorns, and bark of white oak. Images courtesy of Paul Wray, Iowa State University, and Chris Evan, University of Illinois, Bugwood.org. |
Leaves. Alternate, five to nine inches long, three to four inches wide. Oblong shape, seven to nine, rounded lobes; sinuses are rounded as well and their depth can vary from shallow to deep. The white oak is the only known food plant of the Bucculatrix luteella and Bucculatrix ochrisuffusa caterpillars. Leaves usually turn red or even purple in autumn.
Winter buds. Reddish brown, obtuse, one-eighth of an inch long.
Acorns. Sessile or stalked; nut ovoid or oblong, round at the apex, light brown, shiny, three-quarters to an inch long; cap encloses about one-fourth of the nut. White oak acorns have no dormancy, sending down a taproot in the fall with the leaves and stem appearing the next spring. The acorns take only one growing season to develop unlike a red oak acorn, which require two years for maturation.The acorns are much less bitter than the acorns of red oaks, making them a valuable wildlife food; notably for turkeys, wood ducks, pheasants, grackles, jays, nuthatches, thrushes, woodpeckers, rabbits, squirrels, and deer.
Bark. Light gray, varying to dark gray and to white; shallow fissured and scaly. A distinguishing feature of this tree is that a little over halfway up the trunk the bark tends to form overlapping scales that are easily noticed and aid in identification.
Wood. Light brown with paler sapwood; strong, tough, heavy, fine-grained and durable. One cubic foot of wood weighs 46.35 pounds. White oak has tyloses that give the wood a closed cellular structure. Because of this characteristic, white oak is used by coopers to make wine and whiskey barrels as the wood resists leaking. It is also used in construction, shipbuilding, agricultural implements, and in the interior finishing of houses.The USS Constitution is made of white oak and southern live oak, conferring additional resistance to cannon fire. Reconstructive wood replacement of white oak parts comes from a special grove of Quercus alba known as the "Constitution Grove" at Naval Surface Warfare Center Crane Division in Martin County, Indiana.
State Tree. Q. alba serves as the state tree for Connecticut, Illinois, and Maryland. Being the subject of a legend as old as the colony itself, the Charter Oak of Hartford, Connecticut is one of the most famous white oaks in America. An image of the tree adorns the reverse side of the Connecticut state quarter.