On the Nature of Oak Trees

by Fran Withrow 07.2021

I’m a big fan of Doug Tallamy, a University of Delaware professor who advocates for native plants and protection for local wildlife like nobody else. I previously reviewed his book, “Nature’s Best Hope,” in which he explains how we can support biodiversity by what we plant right in our own back yards. I appreciate his congenial, positive approach to promoting environmental causes and his commitment to conservation.

In his newest release, “The Nature of Oaks,” Tallamy hits the ball out of the park once again. This lovely book reveals everything you might want to know about these “keystone” trees that are critical for a healthy ecosystem. Oak trees provide sustenance and shelter for a dizzying array of insects—511 species in Pennsylvania where Tallamy lives—which in turn feed our birds. Other trees don’t even come close: maples host 295, but redbuds provide for a mere 24 species of insects, and sweetgums only 35. 

Tallamy’s book is sectioned by month, and in each one the reader learns more about how incredible oaks are. In January, for instance, many birds survive the bitter weather by feasting on caterpillars hidden in oak bark and crevices. It is a misconception that birds need our feeders to survive: caterpillars are a more nutritious, fat-filled and protein-rich source of food for them. (Not only that, but baby birds cannot digest seeds or insects: therefore caterpillars are the perfect first food for these new hatchlings.) Migratory birds also depend on these yummy morsels of natural goodness.

A good chunk of the book looks at the various insects that thrive on oaks and how important they are to the ongoing life cycle of our ecosystem. Insects hide not only on trees themselves, but also in the leaf litter on the ground. Tallamy says this is a good reason not to rake every last leaf away in the fall. Don’t rake your leaves at all, or at least leave some in designated areas for the insects hidden in, under, and between them.

Tallamy even addresses the myths people have surrounding oaks: they are too large, they fall on houses, they drop massive amounts of leaves, their roots break up sidewalks. You will be pleased to learn that there are ways to avoid these issues and still have oaks in your yard.

There are plenty of color pictures of various oaks as well as the insects and birds who depend on them in this intriguing and informative read. As a bonus, Tallamy also lists good oak choices for the interested homeowner, divided by region as well as by size. So if your yard is small, you can still plant one of these spectacular trees. He even includes a chapter on how to plant an oak. (Hint: it might not be in the best interest of an oak— or your pocketbook— to buy an expensive sapling.)

Have you been outside recently to look at an oak? Go ahead, find one to admire.

I’ll be doing the same.