On the Trail: In praise (and defense) of oaks

Last week I wrote about how the oak-dominated forests of southern Illinois are in trouble due, in part, to almost a century of fire suppression. As such, fire-resistant, sun-loving oaks are being replaced by shade-tolerant beech and maple trees as the old oaks die and there are no young oaks to replace them.

While most folks don't pay attention to which tree species are in the forest, the loss of oaks is a big deal because oak trees are the most common and valuable trees in forests across the country, especially in the east-central United States.

Indeed, the oak was selected as the National Tree by the Arbor Day Foundation, and the white oak is the state tree of Illinois.

In addition to national and state tree honors, oaks probably also deserve to be called the "tree of life" because of the food and shelter they provide to so many wildlife species.

The oak's familiar acorns are an important food source for deer, turkeys, squirrels, black bears and even wood ducks. In fact, over 100 vertebrate species eat acorns. And, properly prepared, acorns are perfectly safe for human consumption and full of nutrients such as iron and manganese.

The cavities that develop in the living and standing dead oaks also provide valuable nesting and roosting habitat for many resident bird species like chickadees, woodpeckers and bluebirds, as well as a variety of migratory songbirds including the great-crested flycatcher and prothonotary warbler.

But the number of insects, especially butterfly and moth caterpillars, that depend on oak leaves is perhaps the most underappreciated "ecosystem service" provided by oak trees. University of Delaware entomologist Douglas Tallamy has estimated that U.S. oaks support almost 1000 species of caterpillars - caterpillars that are essential food for hundreds of songbird species.

The good news is that staff with the Illinois Department of Natural Resources and at the Shawnee National Forest are working to manage southern Illinois' public forests for oak ecosystem health.

Additionally, there are economic incentives provided by the state of Illinois and the U.S. Department of Agriculture to private landowners to help and encourage them to manage their lands for oak ecosystem health, too.

But everyone with a yard can do their part to keep "the tree of life" common in Illinois by choosing to plant an oak tree.

While it is true that oaks are not the fastest-growing trees, the benefits of having oak trees in your yard far outweigh any perceived negatives. In addition to supporting hundreds of butterfly and moth species and providing great fall color and summer shade, your oak tree may live 200 years, making it a great gift to future generations.

So, what are you waiting for? As the old saying goes, "The best time to plant a tree was 20 years ago. The second-best time is today."

For more information about oak ecosystems and forest management in southern Illinois, visit letthesunshinein.life.

Mike Baltz has a doctorate in biology and writes about changing the world from his home in Carbondale.