By Kim Robson:
This is the time of year when autumn leaves are falling in droves, and many of us are toiling (or hiring neighborhood kids) to rake and bag piles of leaves. Most municipalities don’t allow the burning of leaves anymore due to environmental and safety concerns, so all those leaves often end up in the landfill.
But leaves are a critical part of a healthy garden’s ecosystem. Many people mistakenly believe that fallen leaves will kill the lawn below if left over winter. Quite the opposite. With the exception of eucalyptus leaves, which contain defensive biochemicals that can inhibit new undergrowth, fallen leaves are natural sources of important nutrients for your soil’s biology. Instead of putting down fertilizer in the spring, why not just let nature do what She intended?
Put! The Rake! Down!
Fallen leaves are important sources of food and shelter, and also nesting or bedding materials for many birds and other wild animals; and overwintering protection for a number of insects, which further support the birds that forage for them. The soil benefits as well because of the magic of composting, which feeds millions of healthy microbes back into the soil. All these elements in combination work together for a healthy yard.
National Wildlife Federationnaturalist David Mizejewski says, “Fallen leaves offer a double benefit. Leaves form a natural mulch that helps suppress weeds and fertilizes the soil as it breaks down. Why spend money on mulch and fertilizer when you can make your own?”
According to Dr. Thomas Nikoai, a plant and soil specialist at Michigan State University, leaving the leaves alone is “… not only nota problem, it’s awesome.” In an interviewfor Christian Science Monitor, he adds that simply mowing over the fallen leaves will grind them into smaller pieces, thereby enhancing the lawn’s fertility, not killing it off. You can use a mulching mower or a mulching attachment, but really any mower can do the job — just a few times during the fall season is all that’s necessary.
In places where leaves really pile up and may effectively smother an area, just rake them evenly across the yard. If you really need a tidy “park-like” look to your yard, there are lots of alternate things you can do with your leaf harvest, but you’ll still have to rake and bag them:
- Layer them into raised garden beds and flower beds for overwinter protection and to build soil fertility.
- Use them as mulch around the bases of trees to protect the roots from hard frosts.
- Keep a bag of leaves by your home compost pile, and add them as a “brown” layer over “green” kitchen scraps.
- Use them to reclaim sections of the yard that are marginally fertile by leaving a huge leaf pile on the area over winter. By spring, the lower part of the pile will be converted into rich soil, and the rest can be used as mulch or folded into spring garden beds as a soil amendment.
Help Endangered Birds
Messy yards help endangered birds survive the winter. According to the Audubon Society, one-fifth of the bird species in North America are listed as “vulnerable” to population collapse over the next few decades, and there are one billion fewer birds on the continent than there were only forty years ago. Tod Winston, Audubon’s Plants for Birdsprogram manager, says, “Messy is definitely good to provide food and shelter for birds during the cold winter months.”
Audubon Society Tips for Helping Overwintering Birds:
Don’t snip the stems of perennial flowers in the fall. The seed heads of coneflowers, Black-Eyed Susans, and other native wildflowers provide an excellent source of winter calories for birds. “They’re almost invisible, those seeds, but birds eat them all winter long,” Winston says.
Dead plants can provide protein-rich snacks in the form of insect larvae, like the fly and wasp larvae found inside goldenrod galls, for example. Wait until spring to pull them out.
As fallen leaves rot and enrich the soil, they also provide hiding places for insects, salamanders, snails, worms and small frogs that birds can forage for food. “If you’re digging in the garden and come upon these squirmy little coppery-brown dudes, and you don’t know what they are — those are moth pupae,” Winston says. A healthy layer of undisturbed soil and leaf litter encourages more caterpillars, butterflies and moths, which are a crucial protein source for birds.
Got fallen branches from a storm or a Christmas tree to get rid of? Break them into manageable pieces and build a brush pile out of them. American tree sparrows, black-capped chickadees and other winter birds will appreciate the protection from bad weather and predators. Feral cats, rabbits, mice, snakes and other wildlife may also take refuge in it.
Leave native grasses like bluestems or gramas uncut — they make for good foraging after they go to seed. Native grasses, shrubs, trees and flowering plants don’t need chemical fertilizers, which only encourage nonnative plants to grow, making the area uninhabitable for birds. Encourage native dogwoods, hawthorns, sumacs, toyons and other flowering shrubs. Their berries feed birds during the colder months and provide welcome dots of color to a winter yard. Also, evergreens like cedars and firs can provide food and shelter.
To find which native bird species are best suited to the plants in your yard, enter your ZIP code into Audubon’s Native Plants Database.
For more tips and ideas, you can also search for and use the hashtag #LeaveTheLeaves.