The Daily Times

Great Smoky Mountains National Park forestry technicians are continuing their battle against a predator that is less than 1⁄16-inch in length: the hemlock woolly adelgid.

The battleground will move Monday to Cades Cove Loop Raod, where technicians will be

spraying hemlock trees on Cades Cove Loop Road starting Monday. The 11-mile road will be closed to all vehicular traffic on Monday and part of the day on Tuesday. During that time, crews will treat hemlock woolly adelgid-infested hemlock trees with a horticultural oil sprayed from large truck-mounted units. It is a technique they have been using since 2004.

In the event of heavy rain or freezing weather, the operation will be rescheduled.

“In addition to spraying trees in developed areas, the Park is utilizing a systemic pesticide to treat some of the larger hemlocks in the spray zone,” said Jesse Webster, Hemlock Woolly Adelgid Project coordinator. “The systemic treatments move into the tree canopy with sap flow and can effectively control adelgids for five to seven years, which can be a more practical and cost effective approach to management. The spray acts as a quick knockdown allowing the systemics to catch up.”

The Park employs a three-prong approach that also includes the release of predator beetles. All of the chemical and biological control techniques are showing positive effects in areas of these treatments, despite the noticeable decline of tree vigor and mortality throughout the Park.

Currently about 600 acres are being sprayed annually, more than 220,000 hemlock trees have been hand-treated with systemic pesticides spread across 8,000 acres, and about a half-million predator beetles have been released.

Data about the establishment of beetle populations has been positive.

“We’re able to go back to areas with a beetle release, six or seven years ago,” Webster said. “We know now that they are a growing population.”

Protecting the hemlocks is vital. “The Eastern hemlock is a keystone species,” he said. “We’re not just losing the tree itself, but we’re losing the many associated species that are tied to that. We see this as the next possible chestnut blight, but, with this disease, we have some tools we can utilize to control it.”

Hikers allowed

During the full closure on Monday, only hikers will be allowed to travel the Loop Road. Bicyclists will not be allowed to enter the Loop Road for safety reasons since there will be heavy equipment on the road making it unsafe for bicycling. Park personnel will be working at the entrance and exit areas of the Loop.

The spraying operation on Tuesday will only affect the western end of the Loop Road. Motorists and cyclists will be able to enter the Loop as they normally would, but will have to detour across the Loop via Hyatt Lane (the second gravel crossroad) to exit Cades Cove.

The detour will shorten the length of the trip to an eight-mile tour of Cades Cove. The Hyatt Lane bypass will eliminate access to the Cades Cove Visitor Center and Cable Mill area as well as the several trailheads located on the western end of Cades Cove: Abrams Falls, Cooper Road, Rabbit Creek, and Wet Bottom Trails, and Gregory Ridge trailhead.

As part of the Park’s control efforts of the hemlock woolly adelgid, actions include spraying hemlock trees with the oil/soap application in high-use developed areas that are easily accessible by vehicles such as Cades Cove, campgrounds, picnic areas and along roadsides.