Quercus macrocarpa
Overview
The Bur Oak is one of North America’s most massive and long-lived oak species. Known for its large acorns, broad crown, and exceptional durability, it is well adapted to a variety of environmental conditions, including drought, heat, and cold. Its rugged appearance and longevity have made it an important tree of forests, prairies, and cultivated landscapes across much of the United States.
Although Bur Oak is not native to the Appalachian region, it is native to the United States and is widely planted as a shade tree because of its strength, adaptability, and wildlife value.
Identification
Leaves
- Alternate leaf arrangement
- Deeply lobed leaves with rounded lobes
- Distinctive “waist” near the middle of the leaf
- Dark green during the growing season
- Yellow-brown to golden fall color
Bark
- Thick, gray bark
- Deep furrows and prominent ridges
- Highly resistant to fire and environmental stress
Flowers
- Produces inconspicuous flowers in spring
- Male flowers appear as drooping catkins
- Female flowers occur singly or in small clusters
Fruit
- Produces some of the largest acorns among North American oaks
- Acorn caps are fringed with a distinctive mossy or bur-like fringe
- Acorns mature during the second growing season
Size
- Typically grows 60 to 80 feet tall
- Can exceed 100 feet in height
- Mature spread often reaches 60 to 80 feet or more
Native Range
Bur Oak is native to central and eastern North America. Its natural range extends from the Great Plains through portions of the Midwest and into parts of the eastern United States.
The species commonly occurs in prairies, savannas, floodplains, and open woodlands. Its tolerance for both drought and periodic flooding allows it to thrive in a wide variety of habitats.
Within the Marshall University Arboretum, Bur Oak is classified as a United States Native species.
Ecology and Wildlife Value
Bur Oak is one of the most valuable wildlife trees in North America.
Its large acorns provide food for numerous animals, including:
- White-tailed deer
- Wild turkeys
- Squirrels
- Chipmunks
- Blue jays
- Wood ducks
The tree’s extensive canopy provides nesting sites, shelter, and shade for wildlife. Like other oaks, Bur Oak supports a rich community of native insects, which in turn provide food for birds and other animals.
Because of its size and longevity, Bur Oak also plays an important role in carbon storage and ecosystem stability.
Human Uses and Cultural Significance
Bur Oak has long been valued for its strength, durability, and adaptability.
Its wood has been used for:
- Furniture
- Flooring
- Barrels and cooperage
- Construction materials
- Cabinetry
- Interior millwork
The species is also widely planted in parks, campuses, and large landscapes because of its tolerance for urban conditions and its ability to develop into a majestic shade tree.
Individual Bur Oaks can live for several centuries, making them notable landmarks in many communities.
Bur Oak at Marshall University
Bur Oaks add diversity to the Marshall University Arboretum’s collection of oak species. Their large leaves, distinctive acorns, and broad canopies help illustrate the remarkable variety found within the oak genus.
As a United States-native species, Bur Oak also demonstrates the diversity of American forests beyond the Appalachian region while providing valuable wildlife habitat and shade across the campus landscape.
Quick Facts
Common Name: Bur Oak
Scientific Name: Quercus macrocarpa
Family: Fagaceae
Native Region: United States Native
Mature Height: 60-80 feet (occasionally 100+ feet)
Mature Spread: 60-80 feet or more
Growth Rate: Slow to Moderate
Sun Requirements: Full Sun
Soil Preferences: Adaptable; tolerates dry, moist, and occasionally flooded soils
USDA Hardiness Zones: 3-8
Bloom Period: April to May
Fruit/Seed: Large acorns with distinctive fringed caps
Wildlife Value: Acorns provide food for birds and mammals; supports numerous native insects
Notable Characteristics: Massive size, fringed acorn caps, longevity, and exceptional adaptability