By an act of the Illinois General Assembly, the native oak tree was approved as the official state tree of Illinois on February 21, 1908, effective July 1, 1908. The law that originally made the oak the state tree did not specify which one.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 Illinois official state tree.
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.
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.
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.
The law designating the white oak tree as the official Illinois native state tree is found in the Illinois Compiled Statutes, Chapter 5, Section 40.
CHAPTER 5. GENERAL PROVISIONS.
STATE DESIGNATIONS.
(5 ILCS 460/40) (from Ch. 1, par. 2901-40)
Sec. 40. State tree and flower. . The white oak tree is designated the native State tree of the State of Illinois; and the native violet is designated
the native State flower of the State of Illinois.
(Source: P.A. 87-273.)
Taxonomic Hierarchy: White Oak
Kingdom: Plantae - Plants
Subkingdom: Tracheobionta - Vascular plants
Superdivision: Spermatophyta - Seed plants
Division: Magnoliophyta - Flowering plants
Class: Magnoliopsida - Dicotyledons
Subclass: Hamamelididae
Order: Fagales
Family: Fagaceae - Beech family
Genus: Quercus L. - oak
Species: Quercus alba L. - white oak