(Fagaceae Quercus alba)
Adopted in 1907; 1973.
As noted below, the law that
originally made the oak the state tree
did not specify which one. Approximately
20 native species of oak occur in
Illinois. The law was amended in 1973 to
designate the white oak, Fagaceae
Quercus alba, as the official state
The white oak can be very large. Individual trees commonly reach a
height of 30 meters (100 ft.). When
growing in the open, they often have
widely spreading branches. These
characteristics make white oaks
excellent shade trees.
In 1907, Mrs. James C. Fessler of
Rochelle suggested to state officials
that Illinois schoolchildren vote for a
State Tree and State Flower. They
selected the Oak as State Tree.
Sen. Andrew J. Jackson of Rockford
introduced a bill making it official in
1908. In 1973, a special poll of some
900,000 children changed the Official
State Tree from the "Native" Oak to the
White Oak, and the amended bill was
signed into law that year.
White oak (Quercus alba) is an
outstanding tree among all trees and is
widespread across eastern North America.
The most important lumber tree of the
white oak group, growth is good on all
but the driest shallow soils. Its
high-grade wood is useful for many
things, an important one being staves
for barrels, hence the name stave oak.
The acorns are an important food for
many kinds of wildlife.
- Leaf: Alternate, simple,
oblong to ovate in shape, pinnately
veined with an evenly lobed margin,
4 to 7 inches long. The apex is
rounded and the base is
wedge-shaped. Leaves are hairless,
bright green above and whitish
- Flower: Male flowers are
green, borne in naked catkins, 2 to
4 inches long. Female flowers are
reddish and appear as single spikes.
Appearing with the leaves.
- Fruit: Ovoid, but may be
oblong, with a warty cap that covers
1/4 of the fruit. The cap always
detaches at maturity. Matures in one
year, ripens 120 days after
pollination (July to September).
- Twig: Red-brown to
somewhat gray, hairless, with
red-brown multiple terminal buds
that are small, rounded and
hairless. Twigs are often shiny or
- Bark: Whitish or ashy
gray, varying from scaly to
irregularly platy or blocky. On
older trees smooth patches are not
- Form: A large tree; when
open grown, white oaks have rugged,
irregular crowns that are wide
spreading, with a stocky bole. In
the forest crowns are upright and
Plantae -- Plants
Tracheobionta -- Vascular
Spermatophyta – Seed plants
Magnoliophyta – Flowering
Magnoliopsida – Dicotyledons
Fagaceae – Beech
Quercus L. – oak
Quercus alba L. –
Dendrology at Virginia Tech
U.S. Department of Agriculture