ARMN at the Arlington County Fair!

By Devin Reese

Photo of an Arlington County resident holding pamphlets from the ARMN table.
Arlington County resident “Ace” visiting the ARMN table. Photo by Devin Reese.

 During the weekend of Aug. 21-22, ARMN volunteers staffed an information table at the Arlington County Fair. Adjacent to the Virginia Cooperative Extension (VCE) and 4-H Youth Development tables, we were in a great spot for collaboration and outreach with the Fair’s visitors. 

The ARMN table offered a variety of visual materials, including an ARMN poster on Stewardship and Citizen Science, enticing people to plant natives and get involved in bioblitzes and other wildlife inventories. The “Being a Good Neighbor” brochure explained how to adopt practices on your property, such as providing habitat for wildlife to enhance the ecological well-being of neighboring parks. A “Deer Management” handout alerted people to the negative environmental consequences of unmanaged deer populations. Audubon materials were also on display, including “Plants for Birds” and “Making Your Windows Safer for Birds.” The PlantNovaNatives brochure on “Native Perennials for Your Garden” included free seed packets for several native pollinator favorites: Cardinal flower, Milkweed, and New England aster. And a suggested donation of five dollars had visitors taking a copy of the thick, colorful booklet on “Native Plants for Northern Virginia.” 

A steady stream of visitors trickled by the table. Some steered right over at the sight of the wildlife materials, while others were lured with a friendly “Hello.” The variety of interests and intentions visitors brought underscored the broad appeal of connecting with our natural environment. 

Arlington resident, “Ace,” was excited to discuss the diversity of plants she was growing in her apartment balcony garden, which included an eastern redbud (Cercis canadensis) she had been given by Arlington County’s Adopt-a-Tree program. A young couple from Southwest D.C. has no land around their apartment building but dreamed of a future garden. Inspired by the Fair’s agricultural competition, the woman hoped one day to grow a prizewinning gourd, while her husband fantasized about putting Cardinal flowers in his future flower garden. Recognizing the lack of planting opportunities for apartment dwellers, a building superintendent for an 8-unit apartment complex discussed what tenants could plant on their balconies.

Also from Arlington, David came over to ask about how and when to cut back his roses. The Arlington Master Gardener at the adjacent VCE table was able to give him some guidance about pruning them in late fall or early winter after they’ve bloomed. 

Photo of an ARMN volunteer speaking with a visitor with the ARMN booth visible in the background.
Visitor David discussing roses with Master Gardener Joan McIntyre. Photo by Devin Reese.

Two passersby noticed the American goldfinch (Spinus tristis) on the Audubon at Home brochure, and it sparked a conversation about which plants could attract goldfinches to yards. An elementary school girl proudly described the garden she was cultivating by herself and that it was so chock full of plants that she couldn’t add any more.

Some Westover neighborhood residents lamented that they had planted butterfly bushes (Buddleia davidii) but couldn’t seem to keep them alive. This is just as well; Butterfly bush is an invasive, nonnative plant in this region. They took seed packets of the New England aster (Aster novae-angliae) to make a fresh attempt at attracting butterflies with a native plant. Another couple newly-moved to the area were curious about where to buy native plants. Master Naturalist Colt Gregory directed them to Earth Sangha, Nature by Design and the Nova Natives sales at Green Spring Gardens

Photo of an ARMN volunteer holding up an example pamphlet available at the ARMN booth.
Master Naturalist Colt Gregory shares brochures and wisdom with ARMN booth visitors. Photo by Kirsten Conrad.

Editor’s note: see the related piece “Fall 2021 Native Plant Sales” on the ARMN homepage sidebar that lists a number of local native plant sales in September and October. 

There were also visitors stopping to discuss specific environmental concerns. A Maywood neighborhood resident had noticed the die-off of white oaks (Quercus alba). We talked about how oaks in this region are suffering Sudden Oak Death because of a fungal pathogen that infects the living tissue under the bark. (Editor note: Sudden oak death has not yet been detected in the area.) He had also noticed that many trees were colliding with power and phone lines and advocated for moving utility lines underground to make more canopy space for trees. Another resident shared that, while she loved using her compost as rich soil, the unfortunate outcome was lots of stray seeds germinating and shading out the butterfly flower she had intended to grow. 

Photo of two visitors and an ARMN voln
Master Naturalist Marj Signer addresses visitors’ questions. Photo by Kirsten Conrad.

Overall, the combined attraction of the side-by-side tables and lots of visual material related to wildlife and natural resources management seemed like an effective way to ignite conversations at the Arlington County Fair. We even got a visit from the former County Board Chair, the Honorable J. Walter Tejeda! The Fair highlighted just a few of the benefits that ARMN and VCE provide. Plan to contact us with questions you may have about and ways you can support our local natural environment while enjoying its beauty. 

Battling Invasives at Glencarlyn Park

Text and Photos by Devin Reese, except as noted.

Arlington Regional Master Naturalists have a vendetta against invasive plants because of the damage these invaders do to ecosystems. Invasive plants outcompete native plants, disrupting age-old relationships with insect pollinators and typically reducing the biodiversity of an area.

Go on an invasives removal field trip with an ARMN volunteer and you’re guaranteed to witness moments of reckoning between human and plant. Those moments, kicked off by exclamations of dismay such as “Oh no, that’s kudzu!” often involve clipping, lopping, grappling, tugging, hurling, bagging, and otherwise taking invasive plants to the mat. 

If you want to join in the excitement of plant wrestling, there’re plenty of regular outings in Northern Virginia. One of those is the invasives removal program at the Long Branch Nature Center’s Glencarlyn Park in Arlington, monthly on Sunday afternoons. Wear long pants and bring your gloves, clippers, and enthusiasm for helping native plants. The site offers extra gloves and tools if you arrive empty-handed.

One of the people you’re bound to interact with is Long Branch Environmental Steward Steve Young, who is a font of information about the native and introduced flora. He’ll lead you through recognizing and removing invasive plants, while sharing plant-related lore. 

Photo of volunteer holding up a garlic mustard plant
Steve Young shows seed heads on garlic mustard (Alliaria petiolata).

You’ll likely remove garlic mustard (Alliaria petiolata), a common invasive that has cropped up all over the NOVA region. Crush its leaves for a whiff of garlic, which explains its introduction from Europe as a food plant. Despite its tastiness to humans, garlic mustard is not palatable to native wildlife. Because it can self-pollinate or cross pollinate, produce lots of seeds, and grow in shade or sun, garlic mustard spreads fast. Steve will show you how to tug it gently, roots and all, out of the ground, and bag it to keep the seeds off the soil. 

Another plant Steve will point you to is the mile-a-minute vine (Persicaria perfoliata) that was introduced from Asia and first got a foothold in the U.S. at a plant nursery in Pennsylvania, from where it spread. Its delicate stems and leaves bely its hazard as an introduced species. Its other common named, “devil’s tear thumb,” comes from miniscule, curved barbs on the stems and triangular leaves. Using its barbs to cling to other vegetation, mile-a-minute vine grows up to six inches a day, spreading laterally and horizontally. Feel the sticky barbs as you extract the vine from its hold on native vegetation.

Photo of a volunteer pulling a vine
Volunteer Erin removes mile-a-minute vines (Persicaria perfoliata).

Expect Steve to show you some introduced plants that are problematic but cannot be eradicated by pulling them. For example, while small areas of Japanese stiltgrass (Microstegium vimineum) may be removed by hand, it can quickly grow into dense stands to create short, vertical groundcover. Creeping Charlie (Glechoma hederacea) makes ivy-like blankets, but pulling it out will be futile, says Steve. When he first started working at Long Branch about 25 years ago, he says he was “totally anti-chemical and didn’t believe in ever using herbicides.” But he soon realized that “if you don’t use herbicides, you’re going to lose your native plants.” Experienced contractors do regular, targeted herbicide treatments to get rid of invasives that cannot be hand managed.

While battling the invasives, you’ll find moments of gratification in coming across elusive native plants. For example, ghost pipes (Monotropa uniflora), which benefit from the ongoing restoration effort, may peek out of leaf litter with their pale white stems and papery flowers. Lacking chlorophyll, they survive as saprophytes, drawing nutrients from tree roots. Keep your eye out for the equally odd-looking Jack-in-the-Pulpit (Arisaema triphyllum) with its hooded flower. Fold back the hood to see its spike of tiny flowers. The plant is poisonous to humans, but some animals feed on its berries.

Steve may point out the native dogbane (Apocynum cannabinum), that grows in clumps like other bunch grasses. While it is attractive to many insects, Steve notes that this milkweed relative earns its name—it is indeed toxic to mammals.

Photo of the Dogbane plant
Dogbane (Apocynum cannabinum).

The taller native bottlebrush grass (Elymus hystrix) has feathery seed heads. Birds enjoy its grainy seeds. Another is poverty oat grass (Danthonia spicata). While deer resistant, poverty oat grass supplies forage for various insects. These are some of the plants that can transform a yard from turfgrass to habitat for native animals. As Steve says, “these grasses will be taller and won’t look like turf grass, but we have to change our thinking about what a yard can be. Many yards have empty spaces that you would not miss.” 

Photo of a tree sapling in a protective cage

At Glencarlyn Park, you may also encounter some native restoration plantings. Redbud saplings (Cercis canadensis) are enclosed in wire cages to protect them from grazing deer as they mature. 

You may be asked to wrestle the climbing porcelain berry (Ampelopsis brevipedunculata) off the cages to make sure the redbuds get enough access to light. Be careful that you’ve got the right plants, though, because porcelain-berry is closely related to the native grapevines (Vitis spp.) that are valuable to nesting birds. 

Steve’s lively conversation is so information-packed that time passes quickly and you may find yourself looking eagerly forward to the next invasives removal opportunity. 

Learn more on Steve Young’s blog: Plant Whacker, http://www.plantwhacker.com. You can also sign up on the ARMN Volunteer webpage for Arlington County for the Long Branch Park Invasive Plant Removal and other park sessions. The Glencarlyn weed removal event is monthly on Sunday afternoons. 

Additional Wildlife Information (All forms of life that are wild, including plants, animals, and microorganism – Natural Resources Service)

Jack-in-the-Pulpit (Arisaema triphyllum):

One of the more distinctive plants on VA forest floors, Jack-in-the-Pulpit is native to all of eastern North America. Each plant produces a large, fleshy flower on its own stalk, adjacent to a separate stalk with several leaves. The way the flowers’ sheath (the “spathe”) encloses and curls over the flower stalk (the “spadix”) explains its common name. The spadix (Jack), however, is actually hermaphroditic, able to produce male flowers, female flowers, or both. A plant growing just male flowers on the spadix has a hole at the base of the sheath that allows pollinators to do their job and then escape through the bottom. The plants growing just female flowers, however, lack the hole; the theory is that insects get trapped and pollinate as they writhe around.

Learn more on the USFS website about Jack in the Pulpit.

Revitalizing the Pollinator Garden at the Buddie Ford Nature Center

Text and photos by Leslie Cameron

Arlington Regional Master Naturalists joined Extension Master Gardeners and community volunteers on July 17th in an ongoing effort to revitalize the pollinator garden next to the Jerome “Buddie” Ford Nature Center in Alexandria

This hillside pollinator garden contains native plants local to the area, including Upland Ironweed (Vernonia glauca), Sundrops (Oenothera frutica), and various Milkweed species (Asclepias spp.). Many of these inhabit the nearby Dora Kelley Nature Park and the Holmes Run Gorge. The pollinator garden has for several years been an important part of the work the Nature Center to share the wonders of nature with the community, as well as to support our local pollinators.

Photo of the pollinator garden
Pollinator garden at the Buddie Ford Nature Center at the beginning of the day on July 17th.

Unfortunately, the garden has gradually accumulated many invasive species and other weeds that have been crowding out the native plants. Recognizing the need for some serious TLC, Master Naturalist Valerie LaTortue collaborated with Master Gardeners Bob Besse, Mary Lou Leary, and Scarlett Swan to begin a rejuvenation project. They met several times this spring and realized that they needed a lot more help. So, Valerie organized the July 17th volunteer garden day and reached out to other Master Naturalists, Master Gardeners, and park neighbors to pull invasive plants and other weeds from the garden, clear paths, and spread mulch. 

Photo of volunteer Valerie LaTortue weeding in the garden
Master Naturalist Valerie LaTortue, organizer of the volunteer garden day, pulling invasive plants and weeds in the pollinator garden (and too focused on the weeds to look up for a photo 😊).

Although it was a hot day, the volunteers worked tirelessly to uproot stubborn invasive plants and weeds and clear the pathways, filling many yard-waste bags.

Some roots were tough to remove, but the volunteers were tougher!

Photo of volunteer holding a weed with a long root
Nick Nichols wins the prize for longest root pulled—a nasty porcelain berry vine.

And for breaks, volunteers enjoyed snacks, cold water, and Valerie’s herb iced tea under a canopy on the deck overlooking the garden. 

Photo of two containers of iced tea
Valerie’s herb iced tea.

Best of all, the volunteers could enjoy the fruits of their labor right away! Check out Valerie’s video of accomplishments of the day:

Photo of a dirt pathway through the garden
Success! A pathway is now cleared of invasive plants and other weeds in the pollinator garden.

The ongoing work to rejuvenate the pollinator garden is part of a long-term plan to redesign and replant the garden and increase its access to and public education value for the community. In addition to supporting pollinators and improving the ecosystem, Master Naturalists, Master Gardeners, and other area volunteers are helping to reclaim this treasured public education resource for visitors to the Buddie Ford Nature Center and Dora Kelley Park.

More volunteers are needed and welcome! During the foreseeable future, volunteer days are scheduled each Saturday from 9:00-11:00 am (https://armn.org/volunter-alexandria/). Instructions, tools, and refreshments are provided. Volunteers should bring gloves, sunscreen, and insect repellent, and a favorite digging tool if they like.

Paddling for Litter on Four Mile Run Stream

by Devin Reese

Arlington Regional Master Naturalists find ways to improve their local ecosystems not only on land, but also on the water. The Four Mile Run Conservatory Foundation hosts regular stream clean-ups by kayak. All you need to bring is yourself, your enthusiasm for a cleaner stream, and a sense of humor about getting your feet wet. The program provides the boats, paddles, life jackets, gloves, and grabbers for fetching trash from the stream and tossing it into bins. 

Photo of volunteers on kayaks in four mile run creek
The June 5th flotilla of Four Mile Run cleanup volunteers included community members as well as three Arlington Regional Master Naturalists. Photo by Kurt Moser.

When you set out, it’s natural to wonder whether you’ll be able to find and retrieve trash. While it’s not a competition, something about the standardized bin strapped to each kayak ignites your ambition to fill it up fast. Some pickups are quick; your grabbers readily clasp a soda bottle perched on the grassy bank. Some of them take time; plastic bags seem to have a way of burrowing into the soil so that what you think is a quick fetch turns out to be a long tug of war. 

Litter encompasses everything from a multitude of water bottles and cans to larger items like gallon jugs and clothing. Elusive litter shows up in small scraps, such as gum wrappers or bottle labels. Occasionally, you’ll land a big, impressive piece of trash. Those mega-finds have their pros and cons. The Four Mile Run cleanup lore includes a story about the retrieval of a full-sized shopping cart, which had to be strapped on the front of a kayak.

Photo of a bin filled with trash from the creek
Litter bounty is strapped to the front of a kayak. Photo by Devin Reese.

When you’ve filled your bin or fetched an item worthy of showcasing, you paddle for the put-in, a gently sloping dirt ramp where the President of the Four Mile Run Conservatory Foundation, Kurt Moser, waits. He has big trash bags in hand to relieve you of your treasures and get you turned around and back onto the stream as efficiently as possible. Lest it sound like all work and no play however, Kurt also offers granola bars and drinks! 

Each time you launch, you have exciting choices to make—upstream or downstream, right bank or left. Whether you paddle up towards Shirlington or down towards the Potomac, you find plenty of opportunities to load the bin. And you may also find opportunities to chat with people, share what you’re doing, and learn more about how people enjoy Four Mile Run as a natural area. 

Photo of a volunteer holding a channel catfish
Liam proudly displaying the Channel Catfish (Ictalurus punctatus) he caught with his dad, Robert, by the Four Mile Run bridge.

While nestled in an urban area, Four Mile Run stream gets lots of day use by people fishing, jogging, watching birds, and even taking a dip.

After a couple of hours of paddling the stream, especially if it’s a hot day, you may drift into reflections about whether you’re really making a difference. Plucking the litter from the stream bottom or streamside vegetation can be tedious and slow-going. And, as ARMN volunteer Marilynn Lambinicio said, “You won’t necessarily see a change from one cleanup session to another, since litter continues to enter the stream from lots of upstream development.” 

Photo of a volunteer picking up litter while in a kayak
Arlington Regional Master Naturalist Marilynn Lambinicio dumps litter into a bin. Photo by Devin Reese.

Don’t lose sight of the purpose however, as the reward comes in the collective results. The session ends with the flotilla of kayaks pulling back into the put-in area, washing boats, snacking some more, stowing equipment, and amassing the litter loot. At the most recent June 5th kayak cleanup, in just a couple of hours, a group of just eight volunteers retrieved 171 pounds of litter from the Four Mile Run Stream!

Photo of bags of litter collected during the stream clean up

Don’t lose sight of the purpose however, as the reward comes in the collective results. The session ends with the flotilla of kayaks pulling back into the put-in area, washing boats, snacking some more, stowing equipment, and amassing the litter loot. At the most recent June 5th kayak cleanup, in just a couple of hours, a group of just eight volunteers retrieved 171 pounds of litter from the Four Mile Run Stream!

That’s approximately 20 pound each, a phenomenal haul that left the stream looking a lot more inviting for recreation and wildlife.

Would you like to participate in one of these kayak cleanups? If so, see Four Mile Run Conservatory Foundation, or email: info@fourmilerun.org for more information.

Wildlife
Wildlife includes all forms of life that are wild, including plants, animals, and microorganisms according to the Natural Resources Service.

The Channel Catfish (Ictalurus punctatus) is one of the most common fishes caught on Four Mile Run Stream. While native from Canada to Mexico through the central U.S., Channel Catfish were introduced to the eastern U.S. more than a century ago. First observed in Virginia water bodies in 1969, Channel Catfish became established and are now prized for aquaculture and recreational fisheries. Their success stems from opportunistic feeding habits (choosing whatever is available), prolific reproduction, disease resistance, and tolerance for a range of environmental conditions from fresh to brackish waters. While accepted as an important food fish in this region, Channel Catfish may be causing declines of native animals such as crayfishes through competition and predation.

Learn more about the Channel Catfish on the United States Geological Service website.

Two Honors! Glenn Tobin Earned the 2020 Bill Thomas Volunteer Award, and ARMN is presented the Virginia Chapter of the Wildlife Society’s 2021 A. Willis Robertson Award

Glenn Tobin is the 2020 Bill Thomas Park Volunteer Award Winner

Photo of Glenn pulling kudzu vine in front of a creek
Glenn conquering invasive kudzu from Windy Run Park. Photo courtesy of Toni Genberg.

On April 20, 2021, Glenn Tobin received Arlington County’s Bill Thomas Park Volunteer Award for the year 2020. The award recognizes an individual or group whose efforts show ongoing dedication and tangible benefit to Arlington’s natural resources, parks, and public open spaces.

Glenn has been an ARMN member since 2016 and a Trail Maintainer with the Potomac Appalachian Trail Club (PATC) since 2015. For years, he removed invasive plants at Windy Run Park and the adjacent Potomac River waterfront in the George Washington Memorial Parkway. Because of his work alone and with other volunteers, significant natural areas are recovering and becoming more beautiful and biodiverse. In 2020, Glenn raised money and worked with the PATC and the National Park Service (NPS) to rebuild the stone stairway that connects the Windy Run park trail to the Potomac Heritage Trail along the river, improving access for many people. Then, inspired by the reemergence of diverse native flora at Windy Run and along the Potomac, Glenn began working with experts in ecology, botany, and natural resources to create the website, Natural Ecological Communities of Northern Virginia, which provides information about the local natural plant communities to help make better plant selections for ecological restoration purposes in Northern Virginia, Washington D.C., and close-in Maryland. As a result of Glenn’s leadership, ARMN is adopting natural plant communities as a framework for park restoration, in collaboration with local jurisdictions. This work will have lasting impact on restoration planning throughout the County and on selection of plant species for the County’s native plant nursery.

Some of Glenn’s other work includes helping lead Weed Warrior Training with the NPS, assisting in leadership for Park Stewards, and mentoring others who share deep passion for helping restore natural areas in Arlington County and beyond.
(From: The Arlington, VA webpage: “Arlington Honors Park Volunteers”.) 

In a clip from the April 20, 2021 Arlington County Board Meeting, Board Member Karantonis describes Glenn’s accomplishments followed by an address from Glenn. In closing, Chair de Ferranti congratulates Glenn and 2019 Bill Thomas award winner, Elaine Mills: https://youtu.be/oPU84gCj9Lw.

ARMN is selected for the Virginia Chapter of the Wildlife Society’s 2021 A. Willis Robertson Award

On January 29, 2021, ARMN was selected as the 2021 recipient of the A. Willis Robertson Award from the Virginia Chapter of The Wildlife Society for its work on public outreach and education related to deer management. The award honors a wildlife non-professional or group that has exercised outstanding conservation practices on their own land or have made significant contributions to conservation activities in the Commonwealth.

Photo of a plaque in the shape of Virginia for the A. Willis Robertson Award
The Virginia Chapter of The Wildlife Society’s 2021 A. Willis Robertson Award for ARMN. Photo courtesy of Marion Jordan.

In the last few years, members of ARMN led by Bill Browning have spearheaded public education to alert the community to the effects of deer browsing and begin the process of addressing barriers to developing an effective and humane program to control deer population in Arlington County. (See armn.org blog piece, “White-tailed Deer and Forest Health in Northern Virginia” that addresses how deer impact our forests.) The team worked on deer browse surveys, major outreach events with the Virginia Native Plant Society, the Deer Advisory Council for Northern Virginia, Arlington’s Urban Forestry and Environmental Services departments, and in 2019, with regional experts from VA, MD, and DC to create a volunteer training and public presentation that has been delivered over 40 times in the past two years.

Photo of ARMN volunteer Bill Browning
Bill Browning. Photo courtesy of Toni Genberg.

Bill (the 2018 winner of the Bill Thomas award) and the other volunteers have also addressed Arlington County Board members, School Board members, the County Manager, the Chair of the Department of Parks and Recreation, and the Acting Chief of Police. Bill also made presentations to Park and Recreation department employees and to several Arlington County civic commissions who have supported this message with letters to the County Board.

They also talked to civic/neighborhood associations, garden clubs, Extension Master Gardener volunteers, local TV and social media, and spoke at regional parks and conservancy, and hunting club meetings. This outreach has done much to bring the issue forward, engage stakeholders, and provide county decision-makers with sound, unbiased information for their consideration of a deer management plan.

ARMN is excited for this honor and opportunity to credit members like Glenn Tobin for their instrumental work to benefit our local natural environment.

The Virginia Opossum: An Extraordinary Marsupial in Our Own Backyards

by Sandy Sohns

The Virginia opossum is much maligned, and has a reputation as being a repulsive, aggressive, dirty, garbage-eating pest that should be avoided or killed. Sadly, it is misunderstood and is unappreciated for its contribution to the environment, public health, and science.

The Virginia Opossum (Didelphis virginiana) is one of the oldest surviving mammals on the planet, and the only marsupial found in North and Central America, Mexico, and Canada. 

In 1608 in Jamestown, Virginia, John Smith first observed and described the opossum as the size of a cat with the tail of a rat and the head of a pig.

Photo of an opossum
The Virginia opossum is North America’s only marsupial. Image Credit: David Cappaert, Bugwood.org, CC BY NC 3.0.
Photo of an opossum
Photo by Glenn P. Knoblock. Courtesy of Forest Preserve District of Will County.

Males are usually larger than females. They weigh from 4-15 pounds and are 2-3 feet long, including the tail. Opossums have hairless black or white ears, black eyes, a triangular shaped head with a long white face, a pink nose, and mostly dark gray fur. They have 50 teeth, the most of any marsupial. Their front toes have a span of 180 degrees and their opposable great toes on their hind feet act as thumbs and help them grasp and climb. Their scaly mostly hairless prehensile tail also helps with climbing, provides balance, as well as carrying leaves, grass, twigs, or other material for nesting.

Photo of three opossums hanging by their tails
Credit: Frank Lukasseck/Corbis, backyardzoologist.wordpress.com. CC BY NC SA 3.0.

Opossums are generalists, adapting to a wide variety of habitats such as deciduous forests, open woods, marshes, streams, and urban and suburban areas. They move from an area when water and food are not available. They don’t hibernate but they do slow down in cold temperatures; their hairless ears, nose, and tail are susceptible to frostbite. Opossums are not destructive in creating habitat: they don’t dig holes or build burrows. Rather, they’re opportunistic in selecting living arrangements made by other animals or seeking shelter in garages or under sheds. Opossums are not territorial but can be confrontational during mating season or if encountering individuals in their current habitat.

Opossums are nocturnal, solitary, independent, and do not initiate an attack on animals larger than themselves including humans. If confronted by a perceived threat, its offense, which is really bluffing, is to open its mouth showing its teeth, drool, growl, hiss, belch, scream, or screech to scare away whatever is frightening them.

Photo credit: http://www.maxpixels.net. CC0 (Public domain).

If stress increases, their defense—which is an involuntary physiological response—is to collapse. This is what is often called “playing ‘possum.” Their heart rate and respiration decreases, eyes are open or slightly closed, mouth is open, drooling is evident, defecation and urination can occur and if that isn’t enough to ward off whatever is bothering them, they can excrete a foul-smelling green liquid from their paracloacal glands near the base of the tail. This coma-like state can last from a few minutes to 4 or 6 hours.

Photo of an opossum playing dead
Opossum playing dead on back porch of apartment building. Photo by John Ruble. Wikimedia (Public domain).

They are meticulous groomers to keep their fur clean and dry. And it is estimated that they can consume upwards of 5,000 ticks per year. Females are especially fastidious before and after giving birth.

Opossums are omnivores and eat whatever is available including fruit, nuts, insects, frogs, rodents, grass, pet food, garbage, and carrion. They are referred to as “nature’s sanitation engineer” or “nature’s cleanup crew.” Their keen sense of smell and ability to remember where to find food is second only to humans.

They have a low body temperature which is unsuitable for the rabies virus and they are resistant to venomous snake bites due to a naturally occurring protein in their blood, the Lethal Toxic Neutralizing Factor (LTNF) which binds and neutralizes the venoms. This is scientifically important and the NIH’s National Center for Biotechnology Information has found LTNF to be a potent antidote for animal, plant, and bacterial toxins including scorpion and honeybee stings, plant-derived ricin, and botulism toxins.

Opossums have a short life span of 1-2 years. Motor vehicle accidents, hunting and trapping, disease and parasites, exposure and starvation all contribute to their brief existence. While their shy demeanor and proclivity for being killed by cars during their nocturnal food hunts implies decreased intelligence, they outperformed rats and cats in maze testing.

Their reproductive cycle is the shortest of any mammal, 12-13 days, with usually 2 litters a year between December and June. Females may bear as many as 25 babies (also called joeys like their distant kangaroo cousins) but the average survival rate is only 7-9 young. The reasons for this high mortality are many: the embryonic newborns are light pink, blind, about 1/2 inch long, and weigh 0.006 of an ounce. While they have deciduous claws on their front feet to climb up into the pouch, once there, they need to locate one of only 13 teats—some of which will not be viable. Those who make it will remain in the pouch for about 10 weeks, then gradually begin to leave and return to the pouch, and finally be completely weened by about 13 weeks. They stay with the mother for another 3 to 4 months, becoming stronger and independent. Around 7 or 8 months they become sexually mature, and then the mating season begins again.

Photo of an opossum mother with babies on her back
Opossum with babies. Jim Rathert. Photo by MDC Staff, courtesy of Missouri Department of Conservation.
Photo of mother opossum with two babies on her back
Photo by Monica R./Flickr Attribution 2.0 Generic (CC BY 2.0)

The Virginia opossum is indeed a remarkable animal with many distinctive characteristics that is worthy of respect and protection.

References

Krause, William J. and Krause, Winifred A. The Opossum: Its Amazing Story, Research Gate, January 2005. www.researchgate.net/publication/265347494_The_Opossum_Its_Amazing_Story 

“Virginia Opossum Didelphis Virginiana,Nature Worksnhpbs.org/natureworks/opossum.htm 

Kirchner, Jane. “Opossums: Unsung Heroes in the Fight Against Ticks and Lyme Disease,” National Wildlife Federation. June 13, 2017, blog.nwf.org/2017/06/opossums-unsung-heroes-in-the-fight-against-ticks-and-lyme-disease/ 

Debczak Michelle.“13 Facts About Opossums.” Mental Floss. June 8, 2018, www.mentalfloss.com/article/544902/facts-about-opossums

“Creature Feature: Opossums Are Nature’s Pest Control,” The Buzz, March 1, 2019, www.reconnectwithnature.org/news-events/the-buzz/opossum-creature-feature

Sometimes the Small Things Tell the Real Story: Windy Run Park

Text and photos by Glenn Tobin

I was Zoom talking with a small group of ARMN Park Stewards the other day about what inspires us as we help restore ecosystems in our parks. (ARMN Park Stewards are volunteer leaders who work with local park management and staff to help preserve, enhance, restore, and potentially expand the parks’ natural areas, habitats, and ecosystems.)There were many inspirations, but everyone had one in common—seeing how nature begins to heal itself when troublesome invasive plants are removed. It does not happen immediately, but if one observes, the rewards are great. 

Several weeks ago, I was walking along a path I frequent in Windy Run Park in North Arlington. Those who have been there know that the park connects to the George Washington Memorial Parkway and from there to the Potomac River via a steep set of stairs along a beautiful waterfall. 

Photo of a waterfall

As you descend, you might use your right hand to steady yourself along a vertical rock face that extends up from the stairs to far above your head. 

In 2016, that cliff face was covered with English ivy. After getting the o.k. from the National Park Service, I began clearing invasives along the river. The problems were huge in comparison to that small spot. However, I decided to clear it to improve the overall look of the area as I would walk up the stairs. 

As I walked down the stairs several weeks ago, I looked at the cliff face more closely and noticed that a new set of beautiful plants had colonized cracks in the wall from which the ivy had been pulled earlier. Here’s a wide view: 

Photo of plants colonizing a cliff face

Then I started to look more closely. As I saw more and more detail, I also saw more and more beauty—and a great variety of living organisms. Here are two pictures: 

Photo of plants on a rock face
Several types of mosses, likely including spikemoss (Pogonatum sp.) and ferns including a Spleenwort (Asplenium sp.), Mackay’s bladder fern (Cystopteris tenuis) or Blunt woodsia (Woodsia obtusa).
Young versions of the species noted above.

Sometimes I tell people that the process of ecological restoration is like an addictive drug. You rip some ivy off a small rock wall in 30 minutes and then a few years later something like this emerges. It is magical. I dream of a day where we have restored our forests, and the true beauty of biodiverse natural systems becomes obvious to all. 

And there are more improvements to the park than just invasive plant removal. If you know the Windy Run area, you are aware that more than a decade ago, a rockslide destroyed the lower part of the stairs and getting across the boulder field was a bit tricky. Last fall, the stairs and handrail were repaired to address the safety concerns. A unique collaboration across ARMN, the National Park Service, the Potomac Appalachian Trail Club, and a few regular trail users funded stone masons and iron workers to make the necessary repairs. 

The photos below show the before/after stair repairs. The small blue circles provide common reference points across the two pictures. 

Before and after photo of a stair repair project in Windy Run Park.

The new stairs are much more accessible to a wider range of hikers now. Below is some detail of the improved surfaces. 

Windy Run Stair- details of surface through former boulders and uo staircase. Three photos show details of stairs repair.

And finally, this photo shows the new handrail along with the new stairs. 

(The “Warning” sign has since been removed.)

Photo of new railing along Windy Run stairs

Access to Windy Run Park is from the cul de sac at the end of North Kenmore Street, off of Lorcom Lane. The waterfall and stairs are about a half mile away, following the stream. There are four unimproved stream crossings before reaching the top of the stairs (and the stairs themselves are very steep), so the park is not for everyone. You should feel comfortable on rough terrain and crossing potentially wet rocks to make the trip. But if you can manage it, Windy Run Park and the Potomac riverfront along the Potomac Heritage Trail are among the most beautiful spots in the region. 

Yellow-rumps: A Bird Watcher’s Delight in the Winter, Spring, and Fall

Text and photos by Ginger Hays (except as noted)

Photo of a yellow rumped warbler
Yellow-rumped “Myrtle” warbler.

Yellow-rumped warblers ((Setophaga coronateare a very abundant species of the Wood Warbler family—those small, often brightly colored birds that bird watchers go crazy about during spring and fall migration. Bird watchers affectionately call them “butter butts.” There are two primary subspecies of yellow-rumped warblers: the Myrtle warbler, and Audubon’s warbler. The Myrtle warblers are mostly in the eastern United States and Audubon warblers are mostly in the western part of the country.

I love bird watching and think it is a great entryway activity to get people more attached to and involved in protecting the natural world. I also like the meditative act of being alone in a park, yard, or garden and truly having to slow down to see and hear what is around me. I generally have a camera with me when I go out because it helps me record and remember what I have seen.

The yellow-rumped warblers are rewarding—and at times frustrating—for bird watchers. The rewarding part is that there are a lot of them in North America, so you are likely to see and learn how to identify them. They also often hang out in lower-level tree branches, so they are easier to see. But sometimes there will be such a large flock that everywhere you look, all the birds seem to be yellow-rumps. That’s when it can get a little bit frustrating (at least for me), if you are really hoping to see a variety of birds rather than this one species! 

I have met many lovely people on bird walks or hanging out at Monticello Park in Alexandria looking for spring warblers. But just a few weeks ago, I asked a fellow birder her thoughts about yellow-rumps. She said that she likes that they are warblers that you can see in the winter, and though they have more subdued colors in the fall and winter, it is nice because she can watch them more easily when the trees have lost their leaves. This is an interesting aspect to yellow-rumps. Though they do migrate, they don’t go as far south as most warblers, and many stay further north, sometimes as far north as Nova Scotia.

Yellow-rumps use a variety of ways to get their food. They are known to fly out from a branch to catch insects. They can forage on the ground for insects or berries or hang onto a tree trunk or branch. They eat berries from juniper, wax myrtle, Virginia creeper, dogwood, and poison ivy plants. And it is an interesting adaptation that they can digest the wax on juniper and wax myrtle berries. This adaptation enables them to remain further north than other warblers.

Photo of a yellow-rump warbler eating a juniper berry
Yellow-rump non-breeding male eating juniper berry. From: audubon.org website. Photo: Robert Cook/Audubon Photography Awards.

If you look at the range map on the eBird website, you will see that yellow-rumps are present in this area in spring, fall and winter. They only leave for the summer months when they breed in northern parts of the U.S. and in Canada.

So, how do you identify these interesting birds? Well, they do have yellow rumps!

They also may have yellow in three places: on the rump, a spot on the side breast, and—especially breeding males—a yellow spot on their crown. Females and fall warblers are more brown overall, while the breeding male has blue gray on their back and crown streaked with black, and a black mask. 

Myrtle warbles (Setophaga coronata coronate), are the eastern subspecies of the yellow-rumped warbler and they have white throats. These are the yellow-rumped warblers you are likely to see in this area.

There is also a western subspecies, Audubon’s warbler (Setophaga auduboni auduboni), that has a yellow throat, rather than the white throats of the Myrtle warbler. Both of these warblers have what is called a “broken eye ring,” which is white above the eye and white below, but it doesn’t make a full circle.

Photo of a warbler in a bush.
Audubon’s warbler. I took this photo while visiting my sister out in California.

And to make it interesting, there are other wood warblers with yellow rumps: The magnolia warbler (Setophaga magnolia), and Cape May warbler (Setophaga tigrine) have more yellow underparts and generally are not as brightly colored on the backside as the yellow-rump warbler. They all show up in the spring and fall. (Real warbler experts likely know the progression of when they show up. While I don’t, but it is possible that they could all be here at the same time.)

There is a great presentation about warblers, including the yellow-rump, by Bill Young on the Audubon Society for Northern Virginia website: https://www.audubonva.org/online-programs. He includes fabulous pictures of warblers, most of which he took at Monticello Park. 

Finally, I recommend a visit to the bird banding station that usually operates in the spring at Occoquan Bay National Wildlife Refuge. I took these two photos there. I was quite moved by the experience of releasing a bird after it was banded! 

As I mentioned, I love birding, and love how these little guys show how birding can be rewarding any time of year. It gives one a reason to be outside, to slow down and observe, and while one is focusing on the birds, one generally learns something about the plants and wildlife around them!  I hope you find, as I have, that they are a gift that keeps on giving!

How Your Very Own Wildlife Habitat Can Bring Ahhhhhh to These Troubling Times

Text and photos by Toni Genberg

What a wild ride. The past eight months have been a roller coaster of unprecedented challenges—seemingly insurmountable ones at that. I think I can state with a fair amount of confidence that we’ve collectively experienced anxiety, frustration, and also heartbreak. Maybe a bit of anger too. These have been tough days.

Fortunately, there’s this wonderful thing called nature out there. Woodlands, meadows, wetlands … outdoor spaces that allow us to de-stress. There’s no doubt the pandemic has illuminated the value of such protected areas, at least for those of us lucky enough to live near them. 

Photo of tree canopy.
Trees please. This kind of habitat can naturally lift downtrodden spirits.

I’ve had the luxury of spending many hours in some of these nearby natural areas, often to help destroy invasive plants. But a large chunk of my outdoor time is spent in my own personal sanctuary. While the mass movement to visit parks and to simply get outside continues, I experience that decompressing ahhhhhh feeling just footsteps from my door. On this quarter-acre lot four miles from bustling Tysons Corner Center, essential native plants feed uncommon bumble bees, delightful monarch caterpillars, hungry migrating birds, and much, much more.

Left: Photo of a backyard with garden beds. Right: Photo of wildflowers
LEFT: Even a small backyard, when planted with locally native plants, can become a functioning wildlife habitat. RIGHT: Butterfly-weed (Asclepias tuberosa) and narrow-leaf mountain-mint (Pycnanthemum tenuifolium) grow along with other shorter perennials in the front garden.

This habitat did not come about by accident, however. And it wasn’t created overnight. My garden-with-native-plants-or-die journey began about seven years ago with a lecture given by renowned entomologist Dr. Doug Tallamy. His groundbreaking research showed that native plants support all life, even our own. (Yay, science!)

This past February, right before the covid-19 pandemic changed the way we lived, Tallamy’s lecture circuit brought him once again in front of a massive audience in Manassas. His rousing message urged us to repurpose turfgrass with native plants to form our very own “Homegrown National Park.” Reducing just half of all lawns across the country this way would return more than 20 million acres of America to wildlife habitat. Twenty. Million. Acres.

A pandemic prognosticator, Tallamy listed these benefits of building a park at home:

  1. You can enjoy nature on your own time at your own pace
  2. Avoid crowds
  3. It’s free 
  4. Avoid travel hassles
  5. Experience the natural world alone
  6. Hunt lizards!

And now there’s one more benefit: 

  1. Keep safe from droplets!

See what a Tallamy-inspired garden, enthusiastically documented over the past eight months of isolation, has attracted:

Photos of a bird, red bud flowers, and a squirrel.
MARCH: LEFT: This dark-eyed junco (Junco hyemalis), foraging through leaf litter, will eventually make its way north to colder regions. CENTER: Redbud (Cercis canadensis) blossoms are an early source of nectar. RIGHT: Essential to forest regeneration, Eastern gray squirrels (Sciurus carolinensis) are also a constant source of entertainment.
Photos of Carolina wren birds, an eastern tiger swallowtail butterfly, and a white throated sparrow.
APRIL: LEFT: The cutest Carolina wren fledglings (Thryothorus ludovicianus) hatched in the brush pile out back and were raised on an incredible number of spiders. CENTER: A puddling eastern tiger swallowtail (Papilio glaucus) in an area that was once asphalt. RIGHT: White-throated sparrows (Zonotrichia albicollis), here all winter, will depart soon and return again in October.
Photos of a Painted Lady butterfly, a horned passalus be
MAY: LEFT: Painted lady butterflies (Vanessa cardui) lay eggs every spring on plantain-leaved pussytoes (Antennaria plantaginifolia). CENTER: Decaying wood feeds many horned passalus beetles (Odontotaenius disjunctus). RIGHT: This monarch butterfly (Danaus plexippus) showed up on May 4th to lay eggs on common milkweed (Asclepius syriaca).
Photos of a house wren on a bird house, a hoverfly pollinating a sundrop flower, and a brown thrasher bird.
JUNE: LEFT: Yes, I know it’s “just” a house wren (Troglodytes aedon), but I was glad to see her using the unoccupied bird house. CENTER: Sundrops (Oenothera fruticosa) brighten the garden and feed pollinators and other flower visitors—like this margined calligrapher (Toxomerus marginatus). RIGHT: A brown thrasher (Toxostoma rufum) fledgling’s surprise visit. These birds are a declining species that forage in leaf litter.
Photos of a bumblebee visiting a flower, a caterpillar on a black-eyed susan, and a hummingbird drinking nectar from a flower.
JULY: LEFT: A fuzzy bumble bee (Bombus sp.) nectaring on Winged monkeyflower (Mimulus alatus). CENTER: This camouflaged looper caterpillar (Synchlora aerata) dressed up in the bright petals of black-eyed Susan (Rudbeckia hirta). RIGHT: Cardinal flower (Lobelia cardinalis) attracts ruby-throated hummingbirds (Archilochus colubris) and are in turn pollinated by this wee bird.
Photos of a mockingbird perched on elderberry berries, a red oak leaf with holes eaten by insects, and a thistle flower with bees.
AUGUST: LEFT: Common elderberry (Sambucus canadensis) feeds northern mockingbirds (Mimus polyglottos) and many other birds and mammals. CENTER: Oaks such as this northern red oak (Quercus rubra) support the highest numbers of butterfly and moth (Lepidoptera spp.) caterpillars along with other insects. RIGHT: So many animals are attracted to field thistle (Cirsium discolor).
Photos of a male common yellowthroat bird, juvenile goldfinches reaching for food from an adult goldfinch, and a magnolia warbler perched on a twig.
SEPTEMBER: LEFT: A male common yellowthroat (Geothlypis trichas) flits about as it forages in stands of native perennials. CENTER: Feed me! Juvenile American goldfinches mob dad for field thistle (Cirsium discolor) seeds that ripen under the cable line. RIGHT: A migrating magnolia warbler (Setophaga magnolia) whom I hope to see again in the spring.
Photos of a palm warbler, a ruby-crowned kinglet, and a downy woodpecker peeking out a
OCTOBER: LEFT: A sighting first: a pretty palm warbler (Setophaga palmarum), another migratory bird. CENTER: An adorable ruby-crowned kinglet (Regulus calendula) poses on a log I placed for such occasions. RIGHT: A front garden snag-turned-art-carving invites a downy woodpecker (Picoides pubescens) to build a home.

If you’re curious about how best to create your own private park, here are some environmentally-sound suggestions:

  • Buy locally native plants to support our indigenous critters and to keep our wild areas ecologically intact. I like to frequent Earth Sangha’s plant list to choose my local ecotype plants. The Earth Sangha family is always happy to help you to select the right plants for your site conditions and your needs. 
  • If you have an appropriate location, plant native keystone plants such as white oak (Quercus alba) and wild black cherry (Prunus serotina). These trees are the two top supporters of Lepidoptera spp. (moth and butterfly) larvae.
  • Remove invasive plants because they can escape from your yard into natural spaces. Getting rid of invasives on your property is equally as important as planting natives. 
  • Reduce lawn. Turfgrass is considered to be ecologically devastating because of the problematic way humans maintain it (use of fertilizers and weed killers) and because of how little life it supports.
  • Forgo the pesticides. Grub controls, mosquito sprays, and rodent poisons harm more than just the targeted “pests.”
  • Leave the leaf litter to maintain plant and soil health and to harbor a variety of animals. Slugs, moths, and spiders are just as important as our enchanting fireflies and butterflies—which rely on leaf litter to survive.
  • Strive to keep discarded plant material on your property. It takes resources to haul it away and process it.
  • Use some of that unwanted plant material to build a brush pile for birds and small mammals.
  • Leave a dead tree (called a “snag”) standing when feasible. Any size snag can support wildlife but leaving at least a six-foot-tall dead or dying tree feeds innumerable insects and can provide homes for woodpeckers and other animals.
  • Allow branches and logs to rot in your garden or lug neighbors’ chain-sawed tree parts onto your property or do both! These logs make a lovely natural edging and are as enticing to insects as snags are.
  • Keep outdoor lights off to help moths, birds, and bats. Yellow light bulbs in a motion-activated fixture are also a good solution. Note that some studies show that residential exterior lights do not prevent crime.

Although the landscape I nurture is still fluid and an ongoing labor of love (yes, my garden is much more work than lawn is), it has from the get-go provided valuable eco-services. I recommend taking on small sections at a time. Begin by planting lower-maintenance trees and shrubs. Then just add water. And love.

Photo of an insect on a purple flower.
Carolina elephant’s-foot (Elephantopus carolinianus) attracts smaller insects.

There’s never been a better time or reason to create your own oasis. Even if you have only a patio or a balcony, a few native plants grown in containers can attract and support a variety of teeny animals such as our native bees and caterpillars. Let’s help the critters we are passionate about and also help ourselves. 

For more of Tallamy’s philosophy, see: April 2020 Smithsonian Magazine interview, “Meet the Ecologist Who Wants You to Unleash the Wild on Your Backyard.”

Living in the Fall Zone

by Rosemary Jann

Although we may not be aware of it, we live in a region of borderlands. Of course, our area is politically shaped by the explicit borders of the District, Maryland, and Virginia. But the diversity of our plant and animal life derives in part from the fact that the southern limit for many northern species overlaps here with the northern limit for many southern species [https://www.dcr.virginia.gov/natural-heritage/natural-communities/document/ncoverviewphys-veg.pdf, p.23]. We also straddle a third significant geographic borderland, which is responsible for some of the most dramatic features of our region, like the Great Falls of the Potomac depicted below.

Photo of Great Falls
Great Falls of the Potomac, photo from Inspired Vision blogspot, https://ceceliafutch.wordpress.com/2011/06/29/the-magnificent-and-mighty-great-falls-of-the-potomac/.

This border is known as the Atlantic Seaboard Fall Line, formed by the points on eastward-flowing rivers at which navigation becomes impossible because of rapids and waterfalls. This line runs down the mid-Atlantic, as seen in the diagram below, and has shaped the development of this area since its earliest history. The barriers to upstream navigation hindered inland migration by Europeans and spawned cities to their east to facilitate the transfer of goods and people: Georgetown and Alexandria in our area, but also Fredericksburg, Richmond, and Petersburg. Today, Interstate 95 roughly parallels the Fall Line in the mid-Atlantic region.

Image of a map showing the fall lie across North Carolina, Virginia, Matlyand, Delaware, and New Jersey
Diagram of Fall Line, United States Geological Survey, https://pubs.usgs.gov/pp/pp1404-C/pdf/pp_1404-c.pdf, Fig 1, p. C2.

The Fall Line forms along the border between two physiographic provinces that meet in our area. A physiographic province is a geographic region with distinctive soils, topography, and vegetation. The Piedmont province is underlain by hard, crystalline bedrock. In the Coastal Plain, bedrock is deeply covered by softer sedimentary soils. As rivers flowing to the Atlantic over resistant bedrock meet the Coastal Plain, they begin to move more quickly and to cut down through those softer soils, creating waterfalls and rapids as the river descends to sea level [http://www.virginiaplaces.org/regions/fallshape.html]. 

The Great Falls of the Potomac, where the river drops 77 feet in less than a mile [https://www.nps.gov/grfa/learn/nature/naturalfeaturesandecosystems.htm], is the Fall Line’s most dramatic local manifestation. However, the rapids that originally blocked upstream navigation for European immigrants are actually located at Little Falls, slightly north of the Chain Bridge [https://en.wikipedia.org/wiki/Little_Falls_(Potomac_River)]. Over time, the energy of the Potomac has continued to erode the bedrock it flows over, causing the more dramatic waterfalls to migrate westward over millions of years, leaving Great Falls today approximately 14 miles upstream from Washington, DC.

That fact helps underscore the point that it is more accurate to talk about a Fall Zone than a Fall Line. Rather than a knife-edge transition from bedrock to sedimentary soils, the harder rocks of the Piedmont intrude into the Coastal Plain in irregular outcroppings over an area approximately 10 miles wide, creating a ragged boundary with patches of bedrock upthrust into Coastal Plain soils. We can witness this irregular border at Theodore Roosevelt Island, described by the National Park Service as the last bedrock island in the Potomac as it flows eastward to the Chesapeake Bay:  “The island thus marks the Fall Line with bedrock exposures on the northern shoreline (Piedmont) and swamp and tidal marshes on the southern shoreline (Atlantic Coastal Plain)” [http://npshistory.com/publications/gwmp/nrr-2009-128.pdf, p. 14]. Both are illustrated in the photographs below.

When we add the plant diversity that we gain from having vegetation characteristic of both these physiographic provinces in our area, we can fully appreciate the richness of our Fall Zone borderland: it offers a living map to our geological history, serves as a reminder of how our cultural history has been shaped by natural forces, and helps enrich the biodiversity we enjoy as residents of northern Virginia.