Bees (at top) and other wildlife need human help in gardens and lawns long after pollen-gathering has ended

By Pamela Reich

Fall is the time for many of us to tidy up the yard and garden, cut back flower seed heads, and clean up those messy piles of branches and leaves. It may be habit, a matter of social conditioning, or a holdover from outdated gardening practices.

However, these traditional landscaping habits are highly destructive to our native bees, butterflies, and other beneficial creatures trying to survive winter on our properties. Although some of our insects, such as the monarch butterfly, migrate to warmer climates, most of our beneficial insects spend their entire life cycles in and around our yards.

A 2019 United Nations assessment found that up to 40 percent of all beneficial insects are in alarming decline. Habitat loss is one of the largest factors driving these losses worldwide.

• While planting native flowering plants provides important food for our pollinators, these insects also require suitable shelter for nesting and over-wintering to complete their life cycles.
• Cavity-nesting bees, wasps, and moths insert their eggs into the hollow and pithy stems of wildflowers and grasses for overwintering.
• Most bees and wasps create nests beneath the soil or in hollow dead plant stems or cavities in wood.
• Queen bumble bees burrow only one to two inches deep into bare soil to hibernate, relying on a layer of leaf litter for insulation and protection.
• Toads and other small garden creatures use protected spots under leaf litter, in rock walls, brush piles, and under logs and branches to survive the winter.
• In our cool climate, most of our moths and butterflies use leaf litter for winter protection of eggs, caterpillars, chrysalises, or adults. Luna moths encase their cocoons in leaves, and the chrysalises of swallowtail butterflies resemble dried leaves, blending in with the real leaves.
• Red-banded hairstreak butterflies lay their eggs on fallen oak leaves, which become the first food for the caterpillars when they emerge.

As you can see, our lawn care habits greatly influence the survival of our beneficial creatures.

What Can You Do?

Leave dead flower stalks intact over winter. Birds will feed on the seed heads. Cut back stalks in the spring, leaving stem stubble at varying heights of 6 to 24 inches to provide nesting cavities. Female bees will lay their eggs with pollen balls within the stems. Old stems will be camouflaged by new growth and will naturally decay.

Leave small bare spots of soil without mulch around your yard so bees can access the soil. Opt for raking or vacuuming leaves over shredding them with the mower.

Spread raked leaves over flower beds, where they will insulate plant roots and help build the soil.

Pile leaves as mulch around trees and shrubs, on gardens and flower beds. Leaf litter has the same weed suppression and moisture retention properties as shredded wood mulch … and it’s free!

Leave a thin layer of leaves on your lawn. Although a couple of inches of leaves can kill turf, research has shown that a thin layer benefits a lawn by adding organic nutrients as the leaves decompose. Wait until the air temperature reaches 50°F to mow the leaves and to allow the successful emergence of over-wintering bees and butterflies.

About the author

Lower Frederick resident Pamela Reich serves as chair of the township Parks and Recreation Board, is a member of its Comprehensive Plan Steering Committee, and also is a member of the Montgomery County Master Gardener Program. This article is re-published by The Posts from the Lower Frederick Township Newsletter with her permission.

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