The Good of Leaves

Backyard Habitat program manager Susie Peterson wants to save us from laborious fall and winter yard work, while benefiting wildlife and strengthening our gardens and natural areas.

 

Days are getting shorter. Flowers are done blooming, and we’ve swapped our sunny days for the official start to the rainy season. These changes may make it seem like life in your garden is entering a form of hibernation, but underneath your feet many forms of life are just starting their life cycle.

During the warmer summer months, we toil away in the garden planting blooming flowers to feed butterflies, bees, and other pollinators. We’re careful to not use pesticides, knowing the harm they can cause. One of the most important steps we can take to protect the beneficial insects that call our yard home is to shelter their eggs, caterpillars, and chrysalises over the winter months and into the spring. The easiest and most impactful way to do this is by resisting the urge to rake your leaves.

In fact, there are many reasons to give your rake a vacation this fall. Here are a few:

• Beneficial insects often lay their eggs in fallen leaves and hollow stems. While butterflies and bees tend to be the most loved insects, there are many other beneficial insects, such as beetles, millipedes, worms, and spiders, who play an equally important role in your yard’s ecosystem. Most of them also rely on leaf litter for some portion of their life cycle. If you do collect leaves, don’t shred them before adding them to your leaf pile. Shredding will destroy the eggs, caterpillars, and chrysalis.
• A thick layer of leaves provides insulation to ground-nesting insects such as bumblebees. Leave at least a 2” thick layer of leaves to help keep these fuzzy friends warm during the cold winter months.
• Birds and other larger creatures rely on the overwintering eggs and caterpillars as protein-filled foods for themselves and their babies during a time of the year when they aren’t able to forage as much food from plants. Did you know that some moths and butterflies try to trick the birds by disguising their cocoons and chrysalis as dried leaves so they’re less visible?
• Fallen leaves build healthy soils by decomposing and adding important organic matter and nutrients. Leaves also provide as much value in terms of weed suppression as wood mulch products, without the cost. If there are sections of your yard that you can’t resist raking you can create leaf piles in the more hidden corners or spread them out around the base of trees.
• Leaves protect the roots of plants from freezing. Just as bumblebees benefit from the insulating qualities of leaves, so do plants. If you’re worried about frozen leaves weighing down plants and damaging them you can remove the leaves from the crowns of plants and place them around the base of the plant.
• It frees up your time to plant! Due to our rainy season starting this time of year, planting in the fall is the best time to plant in the Pacific Northwest. By not raking leaves you’re freeing up hours of your week to fill in planting beds or replace lawn with beautiful and hardy Willamette Valley natives, or plants unique to your home’s soil and climate if you live outside of the Backyard Habitat program’s service region.

Remember, leaves and other plant materials are nature’s way of supporting soil health, protecting beneficial pollinators, and providing food and nesting materials for birds.

If you tend to be a fastidious gardener consider leaving the quieter parts of your yard wild and covered in leaves and tree debris. These are usually the areas that birds tend to hang out in the most. That way you can satisfy your urge to be tidy in the parts of the yard you visit most while leaving the quieter parts to the birds.

Happy winter gardening!

Susie Peterson
Backyard Habitat Certification Program
Program Manager

The Backyard Habitat Certification Program is a joint partnership between Columbia Land Trust and the Audubon Society of Portland. To learn more visit backyardshabitat.org.