Sarah

Leave (Some of) Your Leaves

Maryland Grows1 Comment

Don’t feel guilty about being a little lazy this fall! Trying to remove every single leaf that lands in your yard is a lot of effort, without all of the reward.

Many municipalities will encourage leaf collection, sometimes distributing collection bags or vacuuming leaf piles from the street. The goal is to prevent leaves from making their way into our stormwater systems, where clogs could lead to flooding in the case of a large rain event. It is therefore important to follow local ordinances to relocate leaves in front and side yards that border a road. However, fallen leaves are valuable resources containing essential nutrients, and you may consider keeping some of this ruby and gold treasure for yourself!

Autumn leaves in reds, oranges, and yellows are beneficial as well as beautiful. Credit: Wikimedia Commons.

Here are some ideas for sustainably managing leaves in back yards and other areas where leaves are unlikely to be washed down a storm drain:

  • Move leaves onto garden and flower beds. You wouldn’t want to leave a thick mat of leaves on your lawn—it would kill the grass beneath; for that same reason, leaf cover is an excellent substitute anywhere you might put mulch. A layer of leaves (aim for at least two inches) will suppress weed growth in overwintering vegetable gardens, perennial flower beds, and around decorative shrubs. To stop the leaves from blowing away, wet them with a hose or watering can. These leaves will decompose slowly, releasing micronutrients back to the soil over time, retaining soil moisture, and helping your plants grow in the spring.
  • If you have more leaves than needed for your landscaping beds, simply mow over them where they fall. Mowing will break leaves down into smaller pieces, both preventing the thick cover that would smother your grass and speeding up the decomposition process. The additional organic matter will benefit your lawn. 
  • Select a sheltered spot in your yard to leave fallen leaves intact. Insects need protection from the winter chill if they are to survive to the spring, and fallen leaves are excellent habitat! They insulate beneficial insects amidst the litter and in the soil below. Don’t mow the leaves in this sheltered spot, or you’ll shred the hibernating insects, too!
Ladybugs need warm, protected spots like leaf piles to survive the winter; as avid aphid-eaters, you’ll be glad to have them in your garden come summer. Credit: PickPik.
  • If you have a backyard composting system, fallen leaves are a great addition! The ideal compost mixture contains a combination of “greens” and “browns” (nitrogen-rich and carbon-rich materials, respectively). Dry leaves are considered “browns.” Crumbling them first will speed up the process.

Whatever options you choose, I highly recommend using rakes or at least electric mowers/leaf blowers over gasoline-powered yard tools, which are noisier and emit pollutants including carbon dioxide, methane, benzene, and other toxic and carcinogenic compounds that harm both human and environmental health. Now, I’ll ‘leaf’ you to it!

Manual yard tools like rakes are a more environmentally-friendly way to move leaves than gas-powered leaf blowers. Credit: Elenathewise, Getty Images.

By Sarah Rothman, Postdoctoral Fellow and Adjunct Faculty in the Department of Environmental Science and Technology at the University of Maryland. Read more by Sarah.

Supporting Migratory Birds

Maryland Grows2 Comments

With the return of warm weather, new plant growth, and emerging insects, you may have noticed the return of bird song, too. Migratory birds begin to return to their breeding grounds in May from locations as far south as Central and South America. Some species will stay in Maryland all summer to nest; others are passing through on their way to breeding grounds farther north. Maryland is under the Atlantic migration flyway, so we have quite a lot of migrating birds in our community, including orioles, warblers, swallows, and more!

Map of North America showing the four major bird migration flyways- the Atlantic Flyway, the Mississippi Flyway, The Central Flyway, and the Pacific Flyway.
Map by American Bird Conservancy

With bird diversity at its peak in our region due to the return of summer species and the temporary presence of northern species on their way home, it’s a great time to go birding! While the Maryland Ornithological Society’s annual May Count has already passed, you can check out their calendar for smaller birding events across the state, including meetings, tours, and educational opportunities.

You can also see which birds are coming and going through the BirdCast Migration Dashboard —enter your county to see how many birds flew over the previous night and cumulatively this season, as well as a list of species to expect this time of year. The Audubon Society hosts an interactive migration map where you can select a location and a bird species to watch where birds travel throughout the year, thanks to data collected from individually-tagged birds.

In addition to tracking their progress and contributing to community science efforts, there are steps you can take to help migratory birds on their journeys:

  • Keep cats indoors or supervise outdoor excursions, as free-roaming outdoor cats frequently prey on birds.
  • Reduce artificial light at night, as birds often fly at night to avoid predators, stay cool, and navigate by the stars and moon. Artificial light from the ground attracts and disorients migratory birds, disrupting their flight paths and increasing collisions with buildings. Minimize light pollution around your home by turning off outside lights, using red bulbs or red gel filters, and/or adding shades to direct light downward instead of up at the sky. You can also put path or porch lights on timers or install motion sensors, so lights are only on when you need them. Close your curtains or blinds at dusk to protect birds from indoor lights.
  • Lastly, an action where gardeners can excel: plant native vegetation to provide fruits and support insects for native birds with varied diets. For example, our Maryland State bird, the beloved Baltimore Oriole (Icterus galbula), which spends the winter in Central America, feeds mostly on insects like caterpillars, beetles, and grasshoppers, but also eats berries and nectar. A native plant like serviceberry (any species in the genus Amelanchier) would be an excellent choice; it can host 124 species of caterpillars and produces fruits that look similar to blueberries, another oriole favorite (any species in the genus Vaccinium). Native birches (like the sweet birch, Betula lenta), plums (like the American plum, Prunus americana), and oaks (like white oak, Quercus alba) also support higher caterpillar abundances, and red mulberry (Morus rubra) and native blackberry species (like the Allegheny blackberry, Rubus allegheniensis) grow attractive fruits.

With these actions, you can help protect our beautiful springtime singers!

Close-up photo of a Baltimore oriole bird.
Baltimore oriole by Andrew Weitzel
Photo of a serviceberry branch and leaves with purple fruits.
Photo of a cluster of ripening blueberries on a plant.
Photo of red mulberry fruits hanging from a shoot.
Photo of blackberry fruits riopening on the plant.

Serviceberry by Native Foods Nursery; blueberry by 88 Acres; red mulberry by K. Dave; blackberry by Ragesoss

By Sarah Rothman, Postdoctoral Fellow in the Department of Environmental Science and Technology at the University of Maryland. Read more by Sarah.