Duke Hollow Stewardship Area

The goal of the Duke Hollow (DH) PRISM site is to create a demonstration project showing that a few people can manage invasive plants on a scale of several hundred acres. The commitment of the landowners to continue monitoring the forest and avoid weed resurgence has been crucial to the success of the project. Positive feedback from witnessing the forest become an inviting place to walk again has been a major incentive driving the work forward. 

History

The forest in DH (located in Clarke County, Virginia) was largely cleared for farming during the 1800s. Today, there is still an original log cabin (ca. 1800) and attached frame house (ca. 1915) at the center of a clearing. Dr. Sanford Rosenthal bought a large part of this area as a family get-away in 1943. The forest regrew as most of the settlements were abandoned by WWII. The Appalachian Trail (AT) was re-routed through the property in the early 1980s. The Barbehenn family inherited and expanded the DH property to include an additional 213 acres (totaling 313 acres after the easement of land for the AT corridor). 

Searching for invasive plants.

An Ecological Challenge

The large clearing around the DH cabin has long attracted birds and the invasive plants that they spread. These include Bittersweet, Wineberry, Japanese Honeysuckle, Privet, Multiflora Rose, and Japanese Barberry. Following the advice of the USDA in the early 1970s, Russian Olive was planted, and it also spread up and down the hollow. With the death of hundreds of elm and ash trees, the DH forest is now riddled with light gaps. Invasive plants are often the first species to take advantage of these gaps, again seeded there by birds. The thickets that have developed in the light can be impenetrable even to deer, and act as productive refuges for invasive plants. Though they are native, species of grapes and greenbriers are also major components of these thickets. Grape vines have been especially damaging to tree saplings, entwining them and preventing their vertical growth, and, as a result, impeding forest regeneration. Not coincidentally, these are also bird-dispersed species. The DH creek is a natural light gap (and bird flyway), and it was heavily colonized by invasive plant species. 

Clearing invasive Wineberry.

Taking Control

Work on removing invasive plants began with periodic efforts around the homesite in the 1990s, but has increased to a year-round effort by Ray Barbehenn (a retired ecologist). Effective strategies to control most of the weeds have been worked out. Primarily, this has involved cutting plants below ground level with loppers to eliminate re-sprouting. Seasonal priorities have been based on eradicating plants before they produce fruit. With the more recent invasion of species such as Japanese stiltgrass, small amounts of herbicides have been required. Opening up the extensive thickets has allowed people to search through the forest efficiently, which has been essential for defending a large area from recolonization by invasive plants. Finally, with work expanding out onto the neighboring properties, the sources of seed being brought into DH by birds have been greatly reduced.

The greatest help from neighbors in recent years has come from the Potomac Appalachian Trail Club (PATC). With about 100 acres of land in the AT corridor through DH, this has long been a swath of land that was largely unmanaged for invasive plants. With leadership by Rob Lamar (the PATC naturalist), groups of PATC volunteers are now contributing to the care of almost the entire area of DH. Blue Ridge PRISM applauds this wonderful partnership between the Barbehenn family and the PATC.

Tree saplings are being planted in deer proof enclosures.

After nine years of continuous stewardship, one limitation for restoring the forest has become clear: White-tailed Deer! Every time a tree falls, it now leaves an opening that cannot fill in again with young trees. The deer are feeding like a herd of goats on tree seedlings and other native plants. Thus, there are usually few, if any, saplings left to replace dead trees. In addition, larger saplings are often badly damaged by bucks that rub them with their antlers during the breeding season. Therefore, any promising saplings that are found in the light gaps are being protected with wire cages or plastic sleeves. In addition, 125 saplings of eight species of trees have been planted in cages where they can fill in the gaps. Active management of the deer herd by hunters is important for protecting the remaining native flora in DH, and is also a source of excellent meat. In a “good” year, as many as 16 deer have been culled. Experience from the DH project suggests that management of an area on par with the home ranges of deer (ca. one square mile) may be important for forest restoration. 🌱