By Jim Hurley
It is now early September, 2012, following the extreme extended heat wave in the Washington DC region, and a walk around Barcroft Park will reveal whole swaths of brown, dead plants at ground level, and many dead tree stems, still upright, listing, or lying on their sides, leaves crisping. It wasn’t the heat that did this.
With the exception of a few big trees felled by the June 29 derecho, most of these browning plants in Barcroft met their demise at the hands of Invasive Plant Control (IPC) technicians, who completed five weeks of an intensive first treatment of 40 acres of the park, providentially, just a few hours before that derecho blew through. The day before, the IPC crew leader walked me, Sarah Archer and Greg Zell through the park to observe the results, which were impressive. Porcelainberry: dead or browning; Multiflora Rose: wilting thickets; Oriental Bittersweet, Japanese Honeysuckle: yellowing or dead; Mimosa, Norway Maple, Japanese Pagoda stems on the ground; 15′ Bush Honeysuckle: cut at the ground, bases painted blue, etc., etc., some 25 species of exotics targeted for destruction.
And what about Tree of Heaven, English Ivy, Periwinkle, and Wintercreeper? Tree of Heaven, really Tree from Hell for the intensity of its infestation of natural areas, roadsides, and farmland in the East, dubbed the Stinkbaum by Germans, was protected by the heat wave. Basal bark treatment, the only way to kill this insidious, suckering spreader, is only effective below 85 degrees, so IPC will be back in the fall to treat this Ailanthus altissima, and in the winter to treat the waxy-leaved evergreen vines, when there will be no collateral damage to the deciduous Virginia Creeper, Wild Yam, and native Grape vines intermixed with them.
Arlington County’s investment of some $75,000 in professional invasive plant control (including two days of treatment for Lesser Celandine in March) in Barcroft Park this Spring, and the County Board’s allocation of $100,000 for invasive plant contract work in FY 2013 (7/1/12 – 6/30/13), a chunk of which will go to follow-up treatments in Barcroft, has completely changed the game, at least for this park. The scale of the infestation was too great for volunteer efforts. We Master Naturalists conducted some 15 invasive pulls in the park in 2011 and 2012, and we had a big impact in several discrete areas, working with partners including the Tree Stewards, Virginia Native Plant Society, Americorps and other volunteers. However, we only made a small dent in the overall problem.
We suspended work in the summer to see the results of the IPC contract work. There will be remnant Porcelainberry, Japanese Honeysuckle, Chinese Yam, etc., still visible in September, but IPC will hit them again next Spring, and in the meantime, we can play a useful role doughnutting the English Ivy climbing trees, which will increase the efficiency of IPC’s Ivy work in the winter. This is the work we performed during our last invasive removal day in Barcroft in May, and it is the work we will do beginning with our next Barcroft Focus Project day this coming Saturday.
So take a walk through Barcroft Park soon, and see the park on its way to natural health. Or better yet, join us at 9:30 this coming Saturday, September 15 to help us complete the work. Afterwards, we will walk the park and identify remnant invasives for IPC to remove. A natural spaciousness is already opening up. This time next year, it will look very different than just a few short months ago.