Common Name of Plant: Bur Oak
Scientific Name of Plant: Quercus macrocarpa

Average Height of Plant: 80 feet or more

Blooming Time: May- June

Ask the Botanist

What are the leaves like?

The leaves are simple, lobed, and about 6-10 inches long. The leaves resemble white oak but the indentation (sinus) midway in the leaves is very deep. The leaves are alternate on the branches but tend to be clustered at the ends of the branches. The underside of the leaf is pale compared to the darker topside.

What type of flowers bloom on this plant? What do the seedpods or seeds look like?

Each bur oak tree has both male and female flowers. The pollen is formed on the yellow-green catkins (male flower) while the much smaller red female flowers produce the acorns (seeds) each year. A burr-like, cup-shaped cap covers each acorn which have a bitter taste. The acorns germinate in autumn.

What is unusual about the stem or trunk?

The bark is dark-gray to black with deep furrows. It has a corky appearance. The thick bark can withstand prairie fires unlike most trees.

How is this plant important to animals? Has it also been used by people?

Many insects eat the leaves of bur oak trees. Squirrels, chipmunks, and other animals use the acorns for food. The wood is heavy, hard, strong and durable. It is used for furniture, interior finishes, and construction. Native Americans used bur oak to treat several illnesses.

What location does this plant prefer?

Bur oaks prefer moist, well-drained soil but can tolerate drought and occasional flooding. They are moderately shade-tolerant. They are especially found in places where forests are changing to prairies and where other types of oak trees are growing.

Pictures

Whole Plant
www.netstate.com/states/symb/trees/ia_oak.htm / Leaf
www.netstate.com/states/symb/trees/ia_oak.htm
Buds / Flowers
extension.usu.edu/.../HomeTown/Select_BurOak.htm
Seeds
www.netstate.com/states/symb/trees/ia_oak.htm / Stem or Tree Bark
extension.usu.edu/.../HomeTown/Select_BurOak.htm