SEPTEMBER

September 18: This Sunday saw three of our Weeding Divas—Donna, Joanne, and Jody—back amidst the Japanese pachysandra in the gorge drainage at the Marie Butler Leven Preserve, the site of our Native Arboretum project. Jody reports that they were joined by two other volunteers—John and his son, Andrew—and the result was a substantial harvest of the offending invasive. Great stuff! Additional news: Tom, perhaps better known in the Diva circle as Denise’s husband, had paid a visit to the Preserve earlier in the week, and cut away the storm damage on the main trail. Jody also reports that she and Joanne are hoping to collect a batch of native ferns, scheduled for rescue in the nearby Scott’s Run drainage, and transplant them into the Preserve, in the area they are clearing of pachysandra. (The Scott’s Run area is going to be bulldozed for a development.) The transplant operation sounds like a good idea to us—not as good as leaving Scott’s Run alone, granted, but if we can’t get that, at least we’ll take the ferns!

September 4: A quartet of “Weeding Divas”—Jody, Denise, Joanne, and Donna—spent several hours this Sunday morning at the Marie Butler Leven Preserve, the site of our Native Arboretum project, to resume their weeding in the gorge drainage. They were joined by Bob and Amy, and their two young sons. Jody reports: “We removed a lot of pachysandra, as well as some vinca, multiflora rose, and bits of ivy trying to get re-established.” Persistence works! Jody also reports that Hurricane Irene downed a few big tree limbs, which fell on the main trail. A Diva spouse (Denise’s husband, Tom) has already been instructed to remedy the situation.

AUGUST

At the Native Arboretum, Georgetown University students begin weeding invasives out of the gorge, on a slope that contains a dense population of native trillium species.

August 23: On Tuesday, 11 incoming Georgetown University freshmen joined Lisa and veteran volunteers Jim Clark and Jerry Schrepple at the Marie Butler Leven Preserve for a weeding project in a sensitive area of the gorge drainage. (Wow. Where else are you going to read a lead like that?) The Preserve is the site of our Native Arboretum project; it is also one of the last remaining areas along this section of the Potomac that is still home to naturally-occurring populations of three native trillium species: large-flowered trillium (Trillium grandiflorum), purple trillium (T. erectum var. erectum), and yellow trillium (T. luteum). The slope that the students were working on is the Preserve’s trillium Serengeti, so to speak. (You can see both flowers and slope in the Native Arboretum Native Plants slide show; see the links panel on the Native Arboretum page.) Unfortunately, that slope is also badly infested with several invasive alien plants that are likely to suppress the trilliums, unless we manage to suppress the invasives first. Hence the weeding project. Among the invasives that the students removed: the ground-cover periwinkle (Vinca minor), and the shrubs burningbush (Euonymus alatus) and Amur honeysuckle (Lonicera maackii). The trilliums are dormant this time of year—their top-growth is now pretty well exhausted and most of their vitality is in their roots—so we don’t have to worry that we’ll hurt them by stepping on them. For several years now, Georgetown students have helped us at our Native Arboretum project, as well as with our work at the Roaches Run Wildfowl Sanctuary. Both parks are better places because of that Georgetown connection.

JUNE

At the Native Arboretum, some of our most experienced volunteers give this slope a thorough weeding.

June 25: More progress this Saturday against the invasive alien burningbush (Euonymus alatus), at our Native Arboretum project. Eleven volunteers, most of them regulars, spent the morning pulling burningbush seedlings in the Preserve’s gorge area. We were pleased to be working with so many of our veterans—board member Bruce Engelbert, Mary Webster (one of our Nursery Watering Divas), Bob and Henry Hassett, Jerry Schrepple, and Andrew Kim, among others. Invasives control might not seem like an ideal organizing principle for community activism but somehow, our members have managed to make it work!

Lisa Williams and her Northern Virginia Community College biology class at the Native Arboretum. That’s Lisa in the front row, second from left. The figure with the hat is Lisa Bright.

June 22: Lisa Williams, a botany professor at Northern Virginia Community College, spent this Wednesday afternoon with 23 of her students at the Marie Butler Leven Preserve, the site of our Native Arboretum project. This was not a tour; it was instead an opportunity for—you guessed it—invasives control. We continued with the task that we had taken up on the 11th: pulling Asiatic tearthumb (Polygonum perfoliatum) along the forest edges. Then we moved into the Preserve’s gorge area to uproot young burningbush (Euonymus alatus) shrubs. The students did a good job; for many of them, this was their first experience with any kind of field biology. We were very pleased that Lisa chose our site for this lesson in “applied botany”!

Volunteer Bob Hassett pursues Asiatic tearthumb along the forest edge at the Native Arboretum.

June 11: This Saturday at the Marie Butler Leven Preserve, the site of our Native Arboretum project, nine volunteers pulled infestations of the invasive alien vine Asiatic tearthumb, or mile-a-minute weed (Polygonum perfoliatum) out of many of our forest-edge work areas. This quick-growing spiny annual vine is a real scourge. We have been able to control it in some parts of the Preserve, but that takes years of pulling and pulling. If you keep doing that, then you eventually exhaust the seed bank, at which point, light weeding prevents new infestations from taking hold. Forget about being clever; persistence is what really matters. That’s the tearthumb lesson for living!

MAY

Friends of Eagle Scout candidate Jonathan Day attack invasive alien vines at the Native Arboretum.

May 28: On Saturday, Eagle Scout candidate Jonathan Day led a group of 25 volunteers in a massive invasive-plant pull at the Marie Butler Leven Preserve, the site of our Native Arboretum project. Jonathan and fellow troop members were working on the slope above the Restored Habitat Area, in the area where the forest borders the lawn adjoining the property’s house. This area was completely covered by Japanese honeysuckle (Lonicera japonica) and Oriental bittersweet (Celastrus orbiculatus). Not any more! Jonathan and crew did a phenomenal job removing the stuff, and they followed up with a planting of appropriate native shrubs and trees, brought in from our Wild Plant Nursery. This was a big step forward for our work in this part of the park: we are now pushing against the invasives from both edges of that forest. Actually, even as Jonathan’s group was clearing the vines along the forest edge, another group of volunteers was working downslope, weeding an area that we had already brought under partial control. We still have a long way to go out there but we’re making strong progress.

MARCH

Patrick Dubois' scout troop reorganize the Native Pollinator Garden.

March 26: Eagle Scout candidate Patrick Dubois and 25 energetic crew members reorganized the Native Pollinator Garden and did a fantastic job. They thinned the tickseed sunflower, wingstem, and coralberry that had overcrowded the garden, and amended the garden by adding a diverse selection of herbaceous plants, all chosen from our Wild Plant Nursery. While Patrick and company worked the Pollinator Garden, a group of Lake Braddock High School students weeded the propagation beds, and Nikki and Alejandro (our University of Virginia volunteer) made wire cages to protect plants from deer. On the lawn near the parking lot, they caged some native hydrangeas that we had put in last year, and created a log border to protect the area from mowing. We hope it will become an attractive addition to the rain garden plantings on the front lawn.

March 23: The Shared Earth Foundation has generously renewed its support of the Sangha, with a $15,000 grant, of which $10,000 has been designated for the Wild Plant Nursery, and the other $5,000 for our "Rethinking Invasives Control" project at the Native Arboretum. Shared Earth was the first foundation to take an interest in the Sangha and has been supporting our nursery since 2001. Caroline Gabel, Shared Earth's CEO, has visited the nursery many times; she has also visited the Native Arboretum twice—evidence, we think, of her keen interest in our work. Caroline is also helping us extend our network of contacts into Maryland. We are very grateful to her for both the networking and the financial support!

At the Native Arboretum, Clemson University students cut invasives at the edge of the southern forest.

March 21: 60 students from Clemson University's Fellowship of Christian Athletes travelled all the way up from South Carolina to join us for a three-day "Service Mission." They spent this Monday with us at the Native Arboretum, removing invasive shrubs and vines from the forest south of the main lawn. They cut back multiflora rose and Amur honeysuckle, as well as porcelainberry and wintercreeper euonymus—and they seemed to have a blast doing it! They sang while they worked, and during their lunch break, they kept up their spirits by playing games—including jump-rope with a porcelainberry vine.

At the Native Arboretum, Lisa points out—and cuts down—an Amur honeysuckle shrub, as Potomac School students prepare to repeat that feat many times over.

March 18: Lisa, Nikki, and Alejandro (a University of Virginia volunteer), spent this Friday morning with a group of 100 students and six teachers from McLean's Potomac School. The group went after the invasives in the section of forest that we had started clearing in January. They cut a huge number of exotic shrubs—mostly multiflora rose, European privet, and Amur honeysuckle. With the shrubs out of the way, we'll soon be able to deal with the groundlayer invasives.

FEBRUARY

Board member Bruce Engelbert (foreground) and two high-school students cut into invasives in the Native Arboretum’s southern forest.

February 6: Lisa Bright, Sangha Board Member Bruce Engelbert, and two high-school students spent Sunday morning at the Marie Butler Leven Preserve, the site of our Native Arboretum project, where they continued our work along the edge of the southern forest. That’s where we had just taken down the park’s last “invasive curtain.” (See the note for January 16.) Lisa, Bruce, and company cut many of the remnant vines and began to push into the vast multiflora-rose tangle that makes up so much of this section of the park. This is not a task for the faint of heart!

JANUARY

The curtain falls! Lake Braddock High School students remove the last “invasive curtain” at the Native Arboretum.

January 16: It was cold this Sunday morning, but that didn’t deter our 19 volunteers, most of them Lake Braddock High School students, from coming out to the Marie Butler Leven Preserve, the site of our Native Arboretum project. We removed the Preserve’s last remaining large-scale invasive curtain. “Curtain” in this context refers to heavy growth of invasive alien vines on trees at woodland edges. The growth can become so heavy that it eventually pull the trees over. Over the past couple of years, we had removed all the curtains at the Preserve except for the one at the south end of the main lawn. Thanks to our cold-hardy volunteers, that one is now gone too! Now what? Read on ...

An invasives-control test plot at the Native Arboretum. This one has worked pretty well; it consists of five layers of heavy paper.

Also January 16: We are preparing what we hope will be a substantial expansion of our invasives-control effort at the Native Arboretum. As part of that effort, we’re planning to open up a new front in the forest south of the main lawn. That’s where the volunteers just cut back the curtain. (See the note above.) But in order to expand our control efforts, we will need to improve our efficiency: We are trying to work out some additional invasives-control techniques that will allow us to cover ground more quickly. We need procedures that can be done easily by volunteers, that are safe, that work well, and that are as cost-effective as possible. Of course, there is an extensive literature on invasives control—but reading is one thing and doing is another, so we decided to test some possibilities ourselves. During 2010, we set up a series of test plots in the southern section of the Preserve’s forest to gauge the suppressive effect of various coverings that are either easily removable or completely biodegradable. We now have a rough scale of effectiveness; we’ll combine that information with pricing, and we hope we’ll be able to put the results to work this spring.