Leaving Leaves

Autumn means raking up every last leaf and clearing dead plant material from the yard — or does it?

Photo A (below) was taken in early December 2020. Tree leaves had fallen, and most plants had entered dormancy, except for several green holdouts. Take a closer look at the Virginia native plant garden in Photo B and find a swallowtail butterfly’s chrysalis attached to the dried stem of a white wood aster (Eurybia divaricata).

While the aster did not host and feed this caterpillar, it’s providing critical habitat during the insect’s pupa stage. Many caterpillars develop on a given plant species and then, to avoid predators looking amongst plants where they know prey live, move to a different location to pupate. This caterpillar likely spent the late summer developing on a nearby tulip poplar (Liriodendron tulipifera) and descended to overwinter as a pupa.

To help this maturing butterfly, fireflies, and other hibernating critters emerge, and to help their eggs hatch next spring, the best and wisest practice is to leave as many husks and fallen foliage as possible where they lie. Raking, blowing, or otherwise wiping out and bagging leaf litter means killing the animals sheltering within those leaves. Some of those leaves and animals can help your yard. Others can help garden areas.

When hibernating insects are mistakenly brought indoors for misguided safe keeping, they enter a warm environment that confuses their cycles, prompting an early emergence when the temperatures are too cold to survive outside and no food sources or mates are available. People might be concerned that some insect pests remain in the debris mix — so will many more predatory insects, spiders, and other beneficial organisms that keep the unwanted bugs at bay. Saving dried, hollow stems offers homes to mason bees — a way to help pollinators without using blossoms. Added bonuses to leaving leaves are:

  • Less yard work (or the expense of paying someone to do it)
  • Saved stalks and twigs hold the leaves in place, preventing them from blowing about
  • When plant matter eventually decomposes, it provides the best compost — far better than wood-based mulch

If you live in one of Fairfax County’s older neighborhoods and have too many leaves to leave on your grassy areas, consider leaving the leaves in the garden and flower beds and using your lawn mower on its highest setting to mulch the ones on the lawn. This feeds the lawn with a natural fertilizer. Michigan State research found an overall reduction in dandelions and crabgrass over time because leaf mulch covered any voids in the turf where the weeds would germinate in the future. This practice may allow homeowners to reduce their herbicide and fertilizer use.

Skipping synthetic yard chemicals is healthier for wildlife and soil microbes. Some plants need trimming, such as low-hanging branches and vegetation flopping across sidewalks. Consider scattering those bits around a garden, adding them to your compost pile, or lastly, sending them off for recycling. Never dump yard debris in natural areas, including parkland. Healthy land stewardship is easy, helps gardens, and encourages butterflies and other beautiful creatures to flourish next year.

Author Greg Sykes is an Invasive Management Area leader for the Fairfax County Park Authority.


Jewell, Susan. 2009. That pesky yard waste: it’s biodegradable, so why can’t I just dump it in the woods? The Fairfax Chronicle 7(2):4. Reprinted with permission at http://www.grsykes.com/pdf/jewell-yard_waste.pdf.





This entry was posted in Uncategorized on by .

About Fairfax County Park Authority

About Fairfax County Park Authority HISTORY: On December 6, 1950, the Fairfax County Board of Supervisors created the Fairfax County Park Authority. The Park Authority was authorized to make decisions concerning land acquisition, park development and operations in Fairfax County, Virginia. To date, 13 park bond referenda have been approved between 1959 and 2016. Today, the Park Authority has 427 parks on more than 23,000 acres of land. We offer 325 miles of trails, our most popular amenity. FACILITIES: The Park system is the primary public mechanism in Fairfax County for the preservation of environmentally sensitive land and resources, areas of historic significance and the provision of recreational facilities and services including: • Nine indoor RECenters with swimming pools, fitness rooms, gyms and class spaces. Cub Run features an indoor water park and on-site naturalist • Eight golf courses from par-3 to championship level, four driving ranges including the new state-of-the-art heated, covered range at Burke Lake Golf Center • Five nature and visitor centers. Also nine Off-Leash Dog Activity areas • Three lakefront parks including Lake Fairfax, Lake Accotink and Burke Lake, with campgrounds at Burke Lake and Lake Fairfax. The Water Mine Family Swimmin’ Hole at Lake Fairfax, Our Special Harbor Sprayground at Lee as well as an indoor water park at Cub Run RECenter • Clemyjontri Park, a fully accessible playground in Great Falls featuring two acres of family friendly fun and a carousel, as well as Chessie’s Big Backyard and a carousel at the Family Recreation Area at Lee District Park • An ice skating rink at Mount Vernon RECenter and the Skate Park in Wakefield Park adjacent to Audrey Moore RECenter • Kidwell Farm, a working farm of the 1930s-era at Frying Pan Farm Park in Herndon, now with historic carousel • Eight distinctive historic properties available for rent • A working grist mill at Colvin Run in Great Falls and a restored 18th century home at Sully Historic Site in Chantilly • A horticulture center at Green Spring Gardens in Annandale • Natural and cultural resources protected by the Natural Resource Management Plan and Cultural Resource Plans, plus an Invasive Management Area program that targets alien plants and utilizes volunteers in restoring native vegetation throughout our community • Picnic shelters, tennis courts, miniature golf courses, disc golf courses, off-leash dog parks, amphitheaters, a marina, kayaking/canoeing center • Provides 263 athletic fields, including 39 synthetic turf fields, and manages athletic field maintenance services at 417 school athletic fields. PARK AUTHORITY BOARD: A 12-member citizen board, appointed by the Fairfax County Board of Supervisors, sets policies and priorities for the Fairfax County Park Authority. Visit https://www.fairfaxcounty.gov/news2/social-hub/ for Fairfax County Government's Comment Policy.

2 thoughts on “Leaving Leaves

  1. Joan Lowy, Quiet Clean NOVA director

    Thank you for this blog post! Leaving the leaves is so important, especially now that we’re facing a global insect decline and so many pollinators are disappearing. Mulching leaves with a lawn mower is a great alternative to using leaf blowers. Next time you might mention that raking leaves into a corner of your yard helps create habitat.


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s