Under the Ice

By Cliff Fairweather

Long Branch naturalist Cliff Fairweather reveals the secrets beneath the  surface of winter freeze.




Snapping Turtle under the ice at Poplar Pond, Long Branch NC (Photo by Cliff Fairweather)

In summer, the ponds at Long Branch and Gulf Branch Nature Centers are a lively places. Green Frogs and bullfrogs sit along the edge or float in the water. Turtles bask on logs and rocks. Northern Watersnakes lie in the sun or patrol the water for frogs to eat. Dragonflies and damselflies zip about in aerial duels or in pursuit of prey.  Green Herons silently stalk fish and frogs.

As fall advances and the weather turns colder, this activity slows and finally ceases, at least above the surface. Beneath the surface, though, the ponds are full of life, even when they are covered by ice. One of the many unusual properties of water is that it gets less dense and lighter as it approaches the freezing point.

Like most substances, water becomes denser and heavier as it gets colder. Water, however, does something odd––it starts to get less dense and lighter after it falls below 39o F (3.8o C). As a result, water colder than 39o F rises above the warmer water. At 32o F (0o C) water turns to ice, which floats on top of the slightly warmer water underneath.

If it didn’t, our ponds would freeze from the bottom up and probably remain mostly frozen all year round. Very little, if any, life could survive in that environment. This is especially important for animals that spend the winter underwater.

Bullfrogs and Green Frogs hibernate at the bottom of the ponds, breathing through their skin. Frogs usually lie on the bottom rather than dig into the oxygen-poor mud because they maintain a relatively high (though still pretty slow) metabolism during hibernation. If they burrowed into the mud, they couldn’t get enough oxygen to survive.

Painted, snapping, and other native aquatic turtles also breathe through their skin during hibernation, but maintain a much lower metabolism than frogs. Consequently, they need less oxygen and can afford to bury themselves in the mud.

In more northern latitudes, where ice can cover ponds and lakes for months and oxygen can be depleted, turtles have another trick up their shell. They can switch to anaerobic respiration, meaning respiration without oxygen.

However, this trick can result in a lethal buildup of acid in their bodies. To counter this, turtles can use buffering agents in their bodies, including the calcium in their shells and bones, to neutralize the acid. Turtles can survive for months this way with little or no oxygen!

Both frogs and turtles sometimes become active under the ice and can be seen moving slowly about. You might also get a glimpse of other winter-active pond life, including fish or aquatic insects such as Water Boatmen and Predaceous Diving Beetles. As cold as it is, the water under the ice is still warmer than the often subfreezing temperatures on land.

Application Period Open for ARMN Spring 2015 Training Class

Adults, standing in marsh, looking through binoculars at somethingTaking the ARMN basic training course changed my life. It opened up so many opportunities to meet great people, get outdoors, and educate the community about nature and its preservation.

~a current ARMN-certified master naturalist

Have a passion for nature? Want to learn how to channel that passion and share it with your community? Apply now to train as a certified master naturalist through ARMN’s 15-week Spring 2015 basic training class. No prior experience is necessary.

Classes will be held on Tuesday evenings from 7 pm to 10 pm at Long Branch Nature Center, beginning February 24 and ending on June 9. (There will be no session on March 31.) In addition, all trainees are required to attend four all-day field trips on selected Saturdays, dates TBA.

Apply by filling out the application available through the Apply tab above and returning it to Long Branch by mail or in person no later than February 1, 2015. Space in this popular course is limited, so act now.

Have a question? Ask it through the Contact Us portal above.

MLK Day Service Opportunities

The Martin Luther King, Jr. holiday is now nationally recognized as a day of service. On January 19, join ARMN volunteers and other like-minded community members at these earth-friendly projects at the times and locations listed. You can also take advantage of upcoming weekend service opportunities listed here in the spirit of Dr. King. We hope to see you at one or more of these events, which are open to the public.

  • ARMN and APAH Join to Save Trees from English Ivy

ARMN will partner with the Arlington Partnership for Affordable Housing to train and lead volunteers in saving trees from the choking hazard of English Ivy at the APAH Columbia Grove property and nearby Bailey’s Branch Park.

Time: Volunteers are needed for both morning and afternoon shifts

Location: Columbia Grove is at 1010 S. Frederick St., Arlington

Contact: Please register with Emily Button (ebutton@apah.org) if you plan to come.

  • Invasive Plant Removal at Gulf Branch Nature Center

Gulf Branch naturalist Jen Soles will lead an invasive plant pull at the park.

Time: 1 – 4 pm

Location: Gulf Branch Nature Center, 3608 Military Rd., Arlington

Contact: Jen Soles (jsoles@arlingtonva.us)

  • Fraser Preserve Japanese Barberry Removal

ARMN volunteer Margaret Chatham will lead removal of Japanese Barberry from Fraser Preserve, a Nature Conservancy property in Great Falls.

Time: 12 – 4 pm

Location: Meet at corner of Springvale Rd. and Allenwood Lane, Great Falls (street parking)

What to wear/bring: Wear layers, sturdy, waterproof boots, and heavy leather gloves. Bring own water (There are no “facilities,” though.); garden forks and strong hand clippers are optional.

Contact: E-mail Margaret Chatham (margaret.chatham@verizon.net) if you plan to come. Call 703.785.8175 after 11 am on MLK Day to check on conditions or if you arrive after the group has gone into the woods. (This number not answered at other times.)

Note: Workday cancelled for frozen ground or heavy precipitation.

Can’t volunteer on MLK Day itself? Consider these two service opportunities on the holiday weekend:

  • Winter Tree ID and RiP Invasive Plant Pull at Tuckahoe Park, January 17

ARMN member Mary McLean will conduct a winter tree identification and follow it with removal of invasive plants at Tuckahoe Park.

Time: 9 – 9:45 am (tree ID); 10 am – 12 pm (invasives pull)

Location: Tuckahoe Park, 2400 North Sycamore St., Arlington

Contact: Mary McLean (marydmclean@verizon.net)

  • Third-Sunday RiP Invasive Pull at Long Branch Park, January 18

ARMN volunteer Steve Young will lead the monthly invasive plant pull at Long Branch Park.

Time: 2 – 4 pm

Location: Long Branch Nature Center Park, 625 S. Carlin Springs Rd., Arlington (Meet in parking lot)

Contact: Steve Young (frazmo@gmail.com)

Restoring Upper Lucky Run: Marginal Mess to Native Meadow

Author Jim Hurley is the outgoing ARMN service committee chair. Here, he describes the transformation of a small patch of Arlington County parkland. 

Text and photos by Jim Hurley

Upper Lucky Run before restoration

Upper Lucky Run before restoration, 2009

In January 2009, after years of looking at a tangled jungle of invasive shrubs and exotic vines climbing into stressed trees along a 100-yard wooded margin on Walter Reed Drive at South Dinwiddie Street in Arlington, I decided to do something about it. Five years later, this former “marginal woodland” is now the County’s largest and cleanest native meadow. How did we get from there to here?

Here’s how it happened….

The site is Arlington County parks property and I needed authorization to do any work there. In February 2009, I invited the park area manager to look at a woodland native plant garden I’d created on private condominium association property across the street. Like Lucky Run, It had also been an overgrown tangle of invasive shrubs, trees, and vines.

The manager quickly got on board with the project. As the Lucky Run site also had canopy trees, we intended to create a similar habitat there. In early April, we mobilized County jail inmates, invasive species technicians, and tree maintenance staff to cut, treat, and remove the woody invasive plants. But then, a week later, I returned after work one day to find several large canopy trees gone, too. Vanished! That morning the site was 80 percent shade; by the evening it was 80 percent sun––a meadow opportunity.

But we would not get to the meadow until the invasive vines growing all over the site were removed. That turned into five months of work for myself and two master naturalist companions. We dug out the English Ivy, Porcelainberry, Japanese Honeysuckle, and Wintercreeper, while preserving the native Virginia Creeper, goldenrods, and asters. I’d set goals for the site: It would have 100 percent native plants, support pollinators, be attractive from the street, bike path, and back yards, and be sustainable with minimal maintenance into the future.

To reach these goals, I sought botanical guidance from Rod Simmons, plant ecologist for the City of Alexandria. From late August to October, Rod led us to a number of meadows in the area, where we collected the seed of native grasses, wildflowers, and herbs that would naturally belong together in a native meadow plant community on a site like Lucky Run. In mid-October, with 90 percent of the site bare dirt, we scattered bags full of mixed seed on the ground and festooned branches and fences with milkweed pods.

Rod had promised us a six-foot meadow by the next summer. I was skeptical. Truth be told, 50 percent of the site was six-foot meadow in 2010, 80 percent in 2011, and 100 percent in 2012. Close enough.

Spring 2014

Spring lushness, 2014

In April 2009 when the work began, there were 70 plant species, 30 of them exotic. Today, there are some 80 native plant species on the site, with only remnant invasives present. Below are two of the pollinator-friendly plants introduced to the site in 2009.


Monarch on Thin-leaved sunflower (Helianthus decapetalus), August 2011


Stand of native Field Thistle, Cirsium discolor, August 2011

It has been interesting to watch the plants find their way and move through the site over the past few years. Strong stands of Devil’s Beggar-ticks (Bidens frondosa) and Late Thoroughwort (Eupatorium serotina) are now largely gone or pushed to the margins by the perennial grasses, goldenrods, asters, and milkweed. The meadow displays a changing guise through all four seasons. A diversity of plants supporting a diversity of insects in a diversity of visual forms flows from one season to the next.

Fall 2014

Fall colors, 2014

All the site needs to maintain it as meadow is several hours of mowing in March, with the dead plant stems dropped onto the ground to preserve the insect eggs sheltered in the hollow stems. In mid-March, the rosettes of leaves of the perennials are just beginning to take off, and so there are just a few weeks when remnant invasive vines can be treated and removed. By mid-April, the meadow has begun to grow in earnest, and any invasive treatment for the remainder of the year risks collateral damage to the native plants. With this minimal annual investment, the meadow can take care of itself well into the future. Without it, the meadow will revert to the tangled mess of 2009.

After annual mowing

Upper Lucky Run after annual mowing

Meet the Litter Critters

Cliff Fairweather
Park Naturalist, Long Branch Nature Center

It happens every autumn, the leaves turn color and then drop to the ground. So why don’t the leaves pile up to the branches, along with all the twigs, branch, and logs that fall throughout the year? A vast army of organisms recycles all that organic material back into the soil, releasing nutrients that support new plant growth. This critical task goes on virtually unseen by the most humans.

Fungi and bacteria do the heavy lifting in this world, decomposing of 80 – 90% of forest detritus. But other than mushrooms, the fruiting bodies of fungi, they are mostly visible only under high magnification. More visible, if you know how to see them, are a wide variety of animals that also play an important role in breaking down all that stuff that falls from the trees. Though some of them are microscopic or nearly so, others are visible with the naked eye or with a magnifier.

Collectively, these animals are often called litter critters, since they dwell in the leaf litter covering the forest floor. Perhaps the best know litter critters are earthworms, which emerge from their burrows at night to feed on dead leaves. Another familiar litter critter is the roly-poly or pill bug. Roly-polies are crustacean rather than an insects and breathe through gills. To keep their gills moist, roly-polies usually stay in the moist microclimate under leaves, logs, or other cover.

A pseudoscorpion uncovered during a ARMN litter critter ID  class, October 5, 2014 (Photo by Cliff Fairweather)

Ready for its closeup: A pseudoscorpion uncovered during an ARMN litter critter ID class, October 5, 2014. (Photo by Cliff Fairweather)

Other readily visible litter critters include slugs, snails, millipedes, adult beetles, beetle grubs, and fly larvae. Much smaller, and usually found under logs, termites play a huge role in decomposing fallen branches and logs. This is because they are among the few animals capable of digesting cellulose, the major component of wood. Smaller still are various springtails (of the order Collembola) and mites. These are best appreciated through a hand lens, although you might spot a bright red velvet mite walking across the dead leaves.

Not all litter critters eat leaf litter. Spiders, centipedes, ground beetles and other tiny predators search the forest floor for other litter critters. And the danger isn’t limited to predatory invertebrates. Salamanders, relative giants in this world, feed on predators and detritivores alike. It’s a real jungle down there!

You can get a glimpse of this world by sifting a few handfuls of leaf litter through some hardware cloth onto a white sheet. Watch for tiny creatures moving a few moments after you stop sifting. A small jar or bug box will help you detain some of these critters for a closer look. But be sure to them back in the leaf litter to continue their important work. They might be tiny, but they are essential to the health of the forest.

Five Favorite Woody and Perennial Native Plants

Just in time for the fall native plant sales (See sidebar), ARMN volunteer Kasha Helget shares some of her favorites for landscaping.

by Kasha Helget

I grow a number of native plants in my yard, but there are some real standouts that deserve special recognition. Here are five each of shrubs and perennials and the features that make them real stars.

First, the shrubs:

by Kasha Helget

Clethra alnifolia (Summersweet) is a good foundation plant to place near an entrance because of its fragrant blooms. It can grow tall or be pruned to be shorter (after the bloom period). It has nice structure even without leaves in the winter. It can handle average moisture conditions and does well in part sun.

Wildlife: Butterfly nectar


Hydrangea quercifolia (Oakleaf Hydrangea) has wonderful year-around interest. First are the big white blooms in spring that smell terrific, and that later become pinkish, and then tan. Even when foliage drops in fall, the dormant flowers look good. It’s a good screening plant even with no leaves. It prefers part shade and average moisture.

Wildlife: Bird habitat


Hypericum frondosum ‘Sunburst’ (St. John’s Wort) is another year-around favorite. It is fast growing, which makes it a good border plant. Its beautiful yellow blooms in spring are a magnet for a variety of bees. It’s a behaved self-seeder, and benefits from pruning after flowering. It can handle average moisture and full to part sun.

Wildlife: Bee nectar

Itea virginica 8-13-14

Itea virginica (Virginia Sweetspire) is a very versatile woody. It can take sun or part shade, and can handle moist or fairy dry conditions. It’s a moderate spreader (suckers) that are easily controlled or can be rooted as new plantings. It’s a great foundation or screening shrub.

Wildlife: Birds; larger mammals.

Symphoricarpos orbiculatus 8-13-14  

Symphoricarpos orbiculatus (Coralberry) is even more versatile than the Itea virginica. It has beautiful foliage all year; great “coral” colored fruit in the winter, likes both shade and sun, can handle dry conditions, its runners are easily transplanted, and it can hold soil on a hill. It doesn’t grow very tall, which makes it a good foundation plant for low windows. While it can get powdery mildew, it can be prevented easily with a baking soda/dish soap/water spray.

Wildlife: Birds (berries); butterflies, moths, and bees (flowers). The dense thickets can provide nest sites.

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Going Batty at Gulf Branch


We’ve all heard of Christmas in July, but how about Halloween in August? The annual Gulf Branch Nature Center Bat Fest on Saturday, August 16, definitely had the feel of a Halloween preview with its celebration of all things bat. The planet’s only true flying mammals got their moment in the sun…er, dusk…with a wide variety of activities that acknowledged their important roles in insect control, pollination, and ecosystem health–– and especially their enormous contribution to international agriculture.


Why Bats Matter: A display from The Save Lucy Campaign (Photo courtesy of David Howell)

There were games of skill, crafts, bat walks, and lectures and live-bat demonstrations, as well as several opportunities to “be” a bat. ARMN volunteer Samantha Gallagher made another one of her whimsical animal boards that allowed bat aficionados of all ages to be photographed as a bat on the wing. To make the experience more authentic, the bat wannabe could chose from a variety of bat nose types to wear in the photograph. (Samantha’s glow-in-the-dark firefly board has been the hit of the past two Firefly Festivals at Fort C.F. Smith.)


A vampire bat and a leaf-nosed bat hit the skies. (Photo courtesy of David Howell)

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A Red-shoulder’s Red Letter Day

by Mary Martha Churchman

On July 11, a Red-shouldered Hawk soared into the trees at Turkey Run Park, as an excited crowd of about forty fans––including ARMN members––watched and applauded and four local TV news channels filmed the release.

The bird’s journey to that moment began one evening in early April, when Mark Stein was walking his dog in the woods at Turkey Run. He noticed a large bird on the ground near the path and was concerned enough to go back the next morning to check on the bird, which was still there. He called the National Park Service Police and stayed with the injured bird until the park police arrived, along with National Park Service (NPS) Biologist and ARMN friend Erik Oberg, to capture the hawk and transport it to Raptor Conservancy of Virginia for recovery and rehabilitation.

According the press release issued by the NPS, “this hawk was likely struck by a vehicle on the George Washington Memorial Parkway. It suffered a concussion and leg injuries but did not have any broken bones.”

Erik Oberg and Gabby Hrycyshyn with the rehabilitated red shouldered hawk

Erik Oberg of NPS and Gabby Hrycyshyn of the Raptor Conservancy with the rehabilitated Red-shouldered Hawk (Photo by Sherrie Burson)

At the Raptor Conservancy center, the adult hawk was treated for its injuries and fed. Once it was medically stable, it was put into a large flight cage to regain its strength for flying––and eventually, hunting.

Before the rehabilitated bird was released, Oberg introduced Mark, the Good Samaritan, who seemed pleased to see the results of his intervention, though slightly embarrassed by the attention, especially from the TV reporters with their notebooks, microphones, and cameras.

As songbirds in the trees loudly signaled their distress, Gabby Hrycyshyn of the Raptor Conservancy of Virginia displayed a flightless Red-shoulder, trained as an education bird, and explained the important role raptors play in local ecology.

When the moment arrived just after noon, Gabby removed the rehabbed hawk from its cardboard pet carrier, held it for a moment while the TV cameras rolled, and then gently tossed the bird aloft. It knew just what to do and soared immediately into the woods, perching on a high branch just long enough to look back over a red shoulder at its admirers before returning home.


ARMN Announces Fall 2014 Training Class

Arlington Regional Master Naturalists is offering a Fall 2014 Basic Training Course beginning September 8 through December 8, 2014, on Mondays from 9 am to 3 pm at Long Branch Nature Center in Arlington, and other locations around the county. (Please note that here will be no class on October 13.) Classroom training will be scheduled for the mornings with field training to follow in the afternoons.

Join a great group of folks of all ages and backgrounds who are interested in learning more about the natural world and our local natural resources –– and how we can all pull together to take care of them. No experience? No problem! Get into or get back to nature by taking the ARMN basic training course.

The deadline for applications is Monday, August 18, 2014. For more information, click on the  Basic Training and Apply tabs above.

Citizen Science: Turkey Run Park Insect ID

Citizen Science: Turkey Run Park Insect ID



Confessions of an Invasives Hitman

By Steve Young

For years, while mercilessly killing non-native invasive plants at Long
Branch Nature Center, I have harbored the admitted fantasy that the
invasives removal will magically reveal some cool, unexpected native
plants. And to be sure, I have seen some nice native plants and have been
able to track how many of them respond positively to the removal of the
invasives. For example, native tree seedlings pop up again in places where
they were choked out before. Plants like Mayapples poke up happily in
vigorous patches where the invasives are gone. I contemplate how plants
like Mayapples are survivors that evolved to cope with the fall of giant
trees on top of them, able to come back years later when the conditions

Back in April, as I enjoyed whacking dense ground webs of Japanese
Honeysuckle, something caught my eye. Around me were many white-flowering
plants of Star (or Great) Chickweed, an under-appreciated native. But this
white-flowered plant was different. A vague memory offered up Dwarf
Ginseng, but I thought “Naw, no way, it’s something else, more common, that
I should recognize.”

Dwarf Ginseng

Dwarf Ginseng (Photo by Steve Young)

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