The white oak (Quercus alba) is the Illinois State Tree. It was
selected for this honor in 1973 by a vote of students in Illinois schools.
What Does It Look Like?
The white oak tree has a broad crown and a short, thick trunk. Its branches are horizontal for the most part. The leaves are bright green on top and pale green underneath. They develop alternately along the twigs. Each leaf has seven to nine rounded lobes. This tree’s bark is gray-white. The acorns are green-brown.
How Big is It?
This species can reach 100 feet tall and four feet in diameter.
Where Does It Live?
The white oak grows in every county in Illinois. It is most often found on wooded slopes and in dry, upland woods. It does not grow well in wet soil.
How Does It Reproduce?
Flowers are produced in April and May. There are male flowers and female flowers on the same tree. The flowers do not have petals. Male flowers develop in drooping, yellow catkins. Female flowers are red and arranged in small groups. The fruits produced from pollinated flowers are acorns. On white oak trees, the acorns may grow singly or in pairs. An acorn may be three-fourths inch long. Its cap covers about one-fourth of the acorn and has warty scales.
What Does It Eat?
This plant doesn’t really “eat” anything! It makes its own food from carbon dioxide and water in the presence of sunlight and chlorophyll in the leaves. The resulting glucose, a simple sugar, is used by the tree for its energy needs.
Does Anything Eat It?
White-tailed deer (Odocoileus virginianus), wild turkey (Meleagris gallopavo), blue jays (Cyanocitta cristata), mallards (Anas platyrhynchos), wood ducks (Aix sponsa), squirrels, raccoons (Procyon lotor), Virginia opossums (Didelphis virginiana), foxes, insects and many other animals eat the acorns. All parts of the tree are eaten by insects. Fungi can decompose and absorb nutrition from the wood. Buds, twigs and leaves are food for a variety of animal species.
What Else Should I Know About It?
• A white oak tree can live for 350 to 400 years.
• The name “white oak” comes from the light color of the tree’s bark.
• The leaves may turn shades of red, gold, brown, yellow or purple in the fall.
• White oak wood is used to make chairs, tables, cabinets, fence posts and other items. It is the most important hardwood lumber tree in the United States.