Governor Bruce Rauner has proclaimed the month of October Oak Awareness Month in Illinois. The proclamation places a spotlight on oak species throughout the state, an important native tree species that is disappearing from Illinois’ landscape.

Oak trees were once abundant throughout the state. In the 1880s, oaks comprised more than 60 percent of the Chicago region’s tree canopy, while today, only 5 percent of the region’s trees are oaks.

The Chicago Region Trees Initiative (CRTI), a coalition of environmentally-focused area organizations, is raising awareness of the beauty, utility, and needs of oak trees during Oak Awareness Month, with its OAK-tober campaign. The campaign includes oak-focused events throughout the state, including oaks and wine tastings, oak woodland walks, oak woodland restoration camping events, and oak planting among others.


Why oaks?

Oak trees are a keystone species, meaning they are trees that entire ecosystems depend on for survival and habitat. Acorns provide food for more than 100 species of wildlife, and an oak tree’s massive trunk and branches shelter countless species of birds and mammals. But they’re slow-growing trees that need space and lots of sunlight to grow and thrive, and in today’s landscape they’re being crowded out by competition from other faster-growing or invasive tree species, and urban development. As the oaks disappear, so does their ecosystem. Oaks are not only struggling in Illinois, but throughout the world — nearly one-third of the world’s oaks are threatened with extinction, due to population growth and climate change.

“Oak trees have not only played an important role in Illinois’ history, but they’re one of our region’s most important native tree species, supporting entire ecosystems — many that are now under severe threat,” said Lydia Scott, director of the Chicago Region Trees Initiative. “When oaks disappear, it produces a tragic domino effect — as the oaks go, so do the birds, animals, and plants that need oaks to survive.”

“Through Oak Awareness Month, we are drawing attention to the importance of oaks, and helping Chicago-area residents, businesses and municipalities understand what they can do to help ensure oaks remain and thrive in our region,” Scott added.

The Oak Recovery Plan

Researchers from CRTI member organizations The Morton Arboretum, Chicago Wilderness and the Lake County Forest Preserve District are currently working on a comprehensive analysis of oak canopy throughout the region and recommendations for the future, with the goal of bringing oak canopy dominance back to our region.

Facts about oak trees:

  • There are approximately 20 species of oaks native to Illinois, including white, swamp white, scarlet, shingle, bur, chinkapin, pin, red, and black oaks.
  • The tallest tree in Illinois, according to the Illinois Big Tree Register, is a 165-foot-tall northern red oak in Dixon Springs State Park, in northern Illinois.
  • Acorns are an important food source for many animals, including deer, gray squirrels, red squirrels, chipmunks, wild turkeys, crows, flying squirrels, rabbits, opossums, blue jays, quail,  raccoons, and wood ducks.
  • Many species of moths and butterflies depend on oaks to reproduce, because their caterpillars feed on oak leaves.
  • In a rainstorm, a 25 inch diameter oak tree can intercept 3,492 gallons of storm water per year, reducing storm runoff.