Origin: Eastern North America (native in Ontario)
White oak is a large tree with a straight trunk and a broad, full crown with spreading branches.Read more about Tree, Bark, Twigs
Leaves have 7 - 9 rounded lobes separated by deep, rounded notches (sinuses).Read more about Leaves
Male and female flowers are borne separately on the same tree, the tiny male flowers clustered in dangling catkins.Read more about Flowers
Fruits are acorns with rounded warty or bumpy cups.Read more about Fruit
White oaks are large trees, up to 35 m (115') in height and 120 cm (4') in diameter, with a broad crown, spreading branches and a straight trunk.
Twigs are green or reddish-green and mostly hairless. As with most oaks, the lateral buds angle out from a broadening of the twig that is like a shelf.
Leaves are 10 - 20 cm (4" - 8") long, smooth on the underside, with round lobes. Leaf shape and number of lobes is variable and lobes may be symmetric or asymmetric.
Fruits are acorns, 12 - 20 mm (1/2" - 3/4") long, with a small point at the tip. Each acorn consists of a nut about 1/4 of which is covered by its warty or bumpy-textured cup.
White oak, with its spreading branches, is one of North America's most stately trees.
White oak is native to the mixed- and deciduous forests of eastern North America, from Ontario and Quebec south to Texas.
White oak is the state tree of Illinois, Maryland, and Connecticut.
White oaks are long-lived trees, capable of living 600 years or more.
Derivation of names
The genus name Quercus, is the classical Latin name for the oaks. The species name, alba, is Latin for white. Early settlers gave white oak its name because of the ashy-grey colour of its bark.
Oaks are divided into two main groups primarily by their leaf shape. Trees in the red oak group have leaves with pointed bristle-tipped lobes while those in the white oak group have either unlobed leaves with large teeth or leaves with rounded lobes. White oak belongs to the white oak group along with bur oak (Quercus macrocarpa), swamp white oak (Quercus bicolor), and English oak (Quercus robur).
White oak acorns are edible and were an important source of food for many Aboriginal peoples. Traditionally, the kernel of the acorn was dried, ground up, and added to soups and cakes. Whole acorns were also roasted in hot coals, then peeled and eaten as a snack. The wood of white oak is commercially valuable and is used to make many products, including panelling, flooring, cabinets, and wine or whiskey barrels. In the past, white oak wood was important in shipbuilding, as it is very strong and does not decay easily.
White oak acorns are a source of food for ducks, white-tailed deer, squirrels, chipmunks, and shrews.
White oak's place in Toronto's urban forestWhite oak was a component of the original oak-pine forests that covered the Toronto region prior to European settlement. A few trees still remain from that time. Many can be seen in North Toronto and along the Avenue Road corridor to Queen's Park. It is still one of the most compatible species with Toronto's sandy soils and is still being planted in parks. Trees Ontario recognizes several specimens as heritage trees.
Landscape value and potential for home planting
White oak grows most successfully in open areas, such as large yards and parks, with well-drained, moist, acidic soil.
Pests and diseases: White oak is affected by the same pests and diseases as bur oak (Quercus macrocarpa). These include gypsy moth (Lymantria dispar), an insect that is native to Europe and Asia. Gypsy moth caterpillars feed on new leaves, often defoliating the whole tree and leaving a tell-tale white frass that hangs from infested trees. If only one defoliation occurs, the tree can recover, but will be weakened; if a tree is repeatedly defoliated, it may die. The City conducts aerial spraying in years predicted to have heavy infestations of gypsy moth. For more information on pests affecting white oak, see Natural Resources Canada factsheet.
This tree is available for planting through the City of Toronto's street tree program.
Find trees on Tree Tour maps at Canadian Tree Tours: