Illinois State Tree
White Oak
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 below.
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 somewhat glaucous.
Bark
Whitish or ashy gray, varying from scaly to irregularly
platy or blocky. On older trees smooth patches are not uncommon.
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 oval.
Conservation; Photos and text by: John Seiler, Edward Jensen,
Alex Niemiera, and John Peterson;Silvics reprinted from Ag
Handbook 654; range map source information