Leaving the leaves helps the environment

For me, from an artistic standpoint, there’s a sort of magic to autumn. It’s not just the brilliant colors that paint the landscape. It’s those days when there are as many leaves on the ground as there are still attached to the trees and I feel as if nature has wrapped the world in a beautiful blanket.

Of course, reality eventually sets in: The discarded leaves turn dull and it’s time to rake. And rake again. And rake some more. While a lot of leaves drop at the same time, there are always the late season hangers-on, like the oak trees that shed their leaves over a long period. But the ongoing chore has an upside.

For years I’ve cheerfully gathered up the leaves, lugging them to the back yard and under the trees in the hedgerow to let them turn into rich humus to later use in my vegetable garden or simply let the nutrients go to the trees. I eventually discovered other benefits to doing this.

Keeping leaves on your property:

— keeps leaves out of the solid waste stream. Leaves and other yard debris account for more than 13 percent of the nation’s solid waste. That’s 33 million tons per year.

— reduces greenhouse gases. Without oxygen to fuel aerobic decomposition, leaves and grass clippings release methane. Not using a leaf blower also helps reduce pollution.

— provides an essential compost ingredient. Fallen leaves provide the “brown” material your compost needs in combination with the “greens.” Browns are needed in a ratio of two to one to greens, and it’s helpful to have them on hand when you need them.

It wasn’t until recently, though, that I learned that keeping leaves on your property also helps wildlife. Reptiles, amphibians, birds, mammals, and invertebrates all rely on leaf “litter” for food, shelter, and nesting material. In addition, many moth and butterfly caterpillars over-winter in fallen leaves.

Which leads me to another point. I used to recommend shredding fallen leaves to use in garden beds, since shredded leaves are easier to work in among plants and look more aesthetically pleasing as well. I was unaware of the importance of leaving leaves intact.

In an example from entomologist and author Doug Tallamy, there are 511 caterpillar species that use oak trees as their host plant. (Not all those species live here, of course.) A few of those species spin their cocoon on the host tree itself. But 480 species fall to the ground when the caterpillar is fully grown, where they either burrow into the soil to pupate underground or spin a cocoon in the leaf litter under the tree. If we run those leaves through a shredder, chances are that we’re cutting up caterpillars as well.

Many of us gardeners have been turning our attention to supporting bees and butterflies by planting pollinator-friendly flowers and shrubs. That’s great, says Tallamy, in his book “Nature’s Best Hope,” but we need to “complete the life cycle.”

He adds, “…for most caterpillar species, only…the egg and larval stages are completed on the host plant. Most caterpillars crawl off their host plant before molting to their pupal stage.”

I feel fortunate that I have that deep hedgerow border on my property where I can leave leaves intact. That may not be possible everywhere. In which case, you can check with your township to see if they have a leaf composting program. This will keep leaves out of the waste stream. Or, you might have a neighbor who has space for more.

Pam Baxter is an avid organic vegetable gardener who lives in Kimberton. Direct e-mail to pamelacbaxter@gmail.com, or send mail to P.O. Box 80, Kimberton, PA 19442. Pam’s books for children—Big Life Lessons from Nature’s Little Secrets, and On Grandpa’s Beach In Maine—are available on Amazon, at Amazon.com/author/pamelabaxter.