Georgia Wildlife Federation

Resources < Wildlife Habitats < Guide to Native Plants of Georgia for Wildlife < Overcup Oak

Overcup Oak is among the most natural-looking and completely informal native oaks of eastern forests. Each leaf is a novelty, with irregular shapes and lobes that are rarely the same, even on a single tree. Its acorns are large and almost completely enveloped by their caps—in fact, it’s difficult to tell that the tree actually does bear acorns because it hides them so well. Unlike other white oaks, Overcup Oak’s acorns are unable to abscise from their caps, perhaps as a camouflaging mechanism against squirrels. Like other oaks, its acorns are edible when the bitter tannins have been leached out by cold water. Cherokee, Creek, and other Native American groups made flour, breads, and cakes from ground acorns. The fall nut crops of oaks were especially important during America’s prehistoric and early colonial history, where the easily stored and relatively nonperishable acorn flour helped societies to survive in wintertime.

Overcup Oak creates dense but irregular shade over time. Like other wetland oaks, it grows slowly but eventually towers over other vegetation and becomes a titanic keystone species of many swampy forests. Its fall nut crops are vital to the survival of many birds and mammals. Its dense shade is useful for providing the foundation for a shade or woodland garden, especially if multiple trees are grown.

Family: Fagaceae (Beech)

Description: Medium sized deciduous tree with a twisted form and pyramidal crown. Bark is gray-brown, scaly, possesses irregular plates, and resembles white oak. Leaves are alternate, simple, 6-10” long, oblong and variable margin with 5-9 irregular lobes. Undersides are white and pubescent. Male flowers are green catkins, while female flowers are reddish single spikes; both appear with the leaves in spring. Fruits are acorns ½-1” long, round, and almost entirely covered by the warty cap. They mature in fall.

Size: 60-80 feet tall and 30-40 feet wide

Habit: Medium to large deciduous tree with a twisted form and pyramidal crown

Growth Rate: Moderate

Light: Full sun to partial shade

Planting and Care: Overcup Oak adapts readily to drier soils but succeeds in wet areas. It is a great choice for swampy areas where other trees may not be able to grow. It tolerates seasonal flooding and poor drainage. For drier soils, particularly for young plants, a 2-4” covering of mulch helps to reduce stress. It does not transplant easily because of its taproot, so be cautious and do not let the trees sit too long in containers.

Ornamental Value: Overcup Oak’s assets include the pleasantly lobed foliage, its height and magnificence at maturity, and its plated gray bark in winter.

Landscape Use: In an open space this tree can be huge and spreading. It prefers moist soil but can tolerate open fields with adequate mulch. It works well as a companion to other native plants like ferns, blackgum, beeches, red maple, buckeyes, white oak, swamp chestnut oak, willow oak, and Shumard oak.

Wildlife Benefits: Overcup Oak’s leaves are a larval food for the Red-spotted Purple, Luna Moth, and Southern Hairstreak. The acorns are relished by woodpeckers, the yellow-bellied sapsucker, the tufted titmouse, and the Carolina wren as well as deer and small mammals like squirrels.

Native Habitat: Native to the Coastal Plain from North Carolina south to northern Florida, west to Texas, and north up the Mississippi River floodplain to Illinois. It favors swamps, wetlands, floodplains, and bottomlands.

Propagation: Fresh acorns sown in the fall. They require stratification to germinate. Cover them with soil and leaves to ensure hungry squirrels don’t find them before spring!