Winter walk: Trees reveal themselves at Corron Farm

The potato chip tree is wild black cherry, easy to spot by its bark. The branches of a red oak reach to the sky while the burr oak's are crooked, the pin oak's reach down and the white oak's reach out like a wide embrace.

Buckeye, chestnut, black walnut, silver maple and basswood were also among trees that Campton Township naturalist Jack Shouba identified Saturday. Shouba led about a dozen people in a nature hike at Corron Farm in Campton Hills for a lesson in reading the landscape in winter.

"We wanted to do a little education and show people what we have here," Shouba said.

Corron Farm was part of an open space purchase that preserved 1,100 acres and 300 acres of farmland, he said. The trail through the woods at the 1830s farmstead was a blend of oaks and invasive species – like the box elder – and some like the wild cherry that are native to Illinois, but don't belong in an oak forest.

Every few steps, Shouba stopped and talked about how to identify trees in a winter landscape. Taking out a small Swiss arm knife, he cut a twig from a tree and described it.

"The twig is thick, and it has a 'face' where a leaf fell off – it's a black walnut," Shouba said, passing the twig around. From the ground, he picked up a few broken walnut shells, adding, "And there are walnuts around. That's a clue."

Another snip of another tree showed a little yellow bud. This, he said, was a yellow-bud hickory, also known as bitternut because the nut is, well, bitter.

Shouba spoke of the wonder of oak trees, especially burr oaks, with their coarse, tough-looking bark.

"That is strong enough to stand up to a prairie fire," Shouba said. "Oaks have a strategy. Their leaves burn in a fire, but their bark is not hurt by fire."

The "strategy" is survival, Shouba said. Its rivals, such as the box elder and maple trees would succumb to a prairie fire, brought on by a lightning strike. Once the rivals are swept away in fire, young oaks can sprout.