As autumn arrives and trees shed their colorful foliage, it's more than a seasonal shift for insects and invertebrates – it's time for them to prepare for winter. But where do these small creatures go? Many remain in their summer areas, becoming less active and seeking shelter under fallen leaves.

Fallen leaves offer vital protection during cold months. The leaf litter acts as insulation, helping butterflies, moths and beetles survive harsh temperatures. Woolly bear and great spangled fritillary caterpillars rely on leaves for protection and food. By leaving fallen leaves in place, you preserve critical habitats.

A growing "Leave the Leaves" campaign is taking root as more people recognize the environmental benefits. The Xerces Society, a leader in invertebrate conservation, offers campaign signs to promote habitat protection awareness.

Benefits beyond invertebrates

Leaving scattered leaves doesn't mean sacrificing tidiness. Consider piling fallen leaves on garden beds, around tree bases or in other strategic areas. The leaf litter acts as natural mulch, protecting plants from cold and retaining moisture while suppressing weed growth.

As leaves decompose, they return organic matter to the soil, boosting health and fertility. This enriches the ground with essential nutrients, promoting healthier plants and improving soil structure. The practice reduces the need for artificial mulch and cuts water consumption. For compost piles, adding carbon-rich "browns" from leaves helps balance nitrogen-rich "greens" from food scraps and grass clippings.

Think before you clear

Before using a rake, mower or leaf blower, consider the invertebrates relying on leaf cover for food, habitat and shelter. Leaving leaves intact – rather than shredding them – protects insects, their eggs and habitat. Removing or grinding leaves can destroy shelter needed for winter survival.

Wait until late spring

When tidying your yard, wait until late spring so overwintering insects can emerge. Many pollinators and beneficial insects won't survive if their leaf cover is removed too early.

Leaving leaves reduces waste. Bagging and hauling them to landfills increases carbon emissions. Raking offers a quieter alternative to leaf blowers, whose emissions contribute to climate change. The practice also aids natural carbon sequestration.

For more information on protecting habitats and invertebrates, visit xerces.org.

Mary Ann Boyer, environmental consultant 

Chestnut Hill