Iowa State Tree

Flower

Staminate flowers borne on catkins. Pistillate flowers borne on spikes.
Appears with the leaves in April or May.

Fruit

Acorns are 3/4 to 1 inch long and nearly round. The cap is flat and
thick, covering about 1/4 of the acorn. Matures in 2 years, ripens August to late October.

Twig

Quite stout, red-brown and glabrous. Terminal buds are multiple, quite
large, ovoid, and covered with red-brown, mostly hairless scales.

Bark

On young stems, smooth. Older bark develops wide, flat-topped ridges
and shallow furrows. The shallow furrows form a pattern resembling ski tracts.

Form

A medium-sized to large tree that develops a short trunk and round crown when open grown, straight with a clear bole when grown with competition.