April 24-May 10, 2026 By Rosemary Jann This April 24–27, ARMN members will once again join other naturalists, as well as families, individuals, and/or groups across the greater Washington DC metropolitan area to participate in one of the largest citizen science events in the world: the City Nature Challenge. The event is a friendly competitionContinueContinue reading “JOIN THE 2026 CITY NATURE CHALLENGE”
Category Archives: News
It’s FINALLY Spring! A Great Time to Shop for and Install Native Plants
Text and photos by Kasha Helget After a rough winter, we’re experiencing warmer days and the return of birds, bees, and butterflies that depend on native plants to survive and feed their young. Native plants also provide beauty to our pots, yards, and landscapes. Where to find them? Actually, the timing is excellent because thereContinueContinue reading “It’s FINALLY Spring! A Great Time to Shop for and Install Native Plants”
The Evolving Role of Wildland Fire in Virginia
Arlington Forest Park, designated by Arlington County as a natural resource conservation area for its rare oak savanna ecosystem. Photo by Dan Brown. Nature parks in our area are managed to support native plant communities, often the oak/hickory forest type. But some parks don’t much resemble the original landscapes because a key factor is missing:ContinueContinue reading “The Evolving Role of Wildland Fire in Virginia”
The Hidden Helpers of Our Forests: Mycorrhizal Fungi and the Web of Life Beneath Our Feet
By Laura Gilmore Local forests depend on invisible partnerships beneath the soil. Photo of Long Branch Stream in Glencarlyn Park by Marianna Cardozo. When we walk through a forest in Northern Virginia, whether it’s the hardwoods of Potomac Overlook Regional Park or the woodlands of Glencarlyn Park in Arlington, it’s easy to focus on whatContinueContinue reading “The Hidden Helpers of Our Forests: Mycorrhizal Fungi and the Web of Life Beneath Our Feet”
Geology Walk in Holmes Run Gorge
Text and photos by Hutch Brown. On August 30, 2025, several ARMN members joined local residents for a geology walk in Holmes Run Gorge hosted by the Northern Virginia Mineral Club and Friends of Holmes Run. Holmes Run, part of Alexandria’s Cameron Run watershed, cuts a gorge through the Piedmont bedrock (the foundational rock underlyingContinueContinue reading “Geology Walk in Holmes Run Gorge”
2026 Martin Luther King, Jr., Weekend
Nature Volunteering Events ARMN and other local environmental groups are hosting several events in honor of Martin Luther King, Jr. between Jan 16 and 19, 2026. Here is a list of opportunities to work with fellow community members to remove non-native invasive plants and clean up our area’s beautiful parks and spaces. Please check theContinueContinue reading “2026 Martin Luther King, Jr., Weekend “
Fossils Along Our Local Creeks
Text and photos by Hutch Brown. Skolithos linearis fossils found along Four Mile Run (top) andHolmes Run (bottom). I was walking along Four Mile Run in Arlington’s Barcroft Park when I found the rock at the right (5” X 5”, with loupe for scale) on a gravel bar. I’ve seen others like it near otherContinueContinue reading “Fossils Along Our Local Creeks “
What’s Eating You, Emerald Ash Borer?
By Roderick Mackler Most of you have at least a passing familiarity with the emerald ash borer (Agrilus planipennis). The bright green beetle is decimating the ash trees on the eastern half of North America, from Ontario to Virginia. Females lay their eggs in the crevices in the bark of ash trees (several species ofContinueContinue reading “What’s Eating You, Emerald Ash Borer?”
Fall Migration: Not Just for the Birds!
By Colleen O’Hara Fall is a great time to spot migrating birds in our area, thanks to Arlington’s location along the Atlantic Flyway—a major route for migratory birds. But birds aren’t the only things on the move. The monarch butterfly, common green darner dragonfly, American eel, and the Eastern red bat are among the otherContinueContinue reading “Fall Migration: Not Just for the Birds!”
Autumn 2025 Native Plant Sales: The Best Time of Year to Install New Natives!
Text and photos by Kasha Helget Think you have to wait till next spring to purchase native plants? Think again!! Below are locations where you can purchase the perfect plants to benefit local wildlife and spruce up your yard, too. Autumn is the best time to install new perennials, trees, and shrubs with warmer soilsContinueContinue reading “Autumn 2025 Native Plant Sales: The Best Time of Year to Install New Natives!”