Invasive and Exotic Species

Hemlock Woolly Adelgid Survey in Georgia

By: James K. Johnson

Forest Health Coordinator, Georgia Forestry Commission

A survey for the Hemlock Woolly Adelgid was initiated in Georgia in 2003 with one full time position. In 2004, the GFC funded one person full time and another person one-half time. These employees surveyed hemlock stands throughout its natural range to determine if the Hemlock Woolly Adelgid has invaded Georgia and the levels of infestation and damage where it is occurring.

Counties

Ten counties were included in the survey area, covering about 2000 square miles: Rabun, Towns, Habersham, White, Union, Fannin, Gilmer, Murray, Dawson (partial) and Lumpkin (partial). HWA was found to be present in Rabun, Towns, Habersham, White and Union counties. Severe infestations are occurring in the Burrells Ford area.

HWA has spread west and south into Georgia. We found no HWA west of the Nottley River headwaters. In White County, HWA was found as far south as Dukes Creek in the Chattahoochee watershed. The heaviest infestations are in the Chattooga, Little Tennessee, Tallulah and Hiawassee watersheds and in the headwaters of Brasstown Creek (Union, Towns). Other watersheds with lighter infestations are the Soque, Chattahoochee, and Nottley.

2004 Predator Beetle Releases in Georgia

GFC employees identified appropriate sites for the release of biological control agents in the Chattooga River watershed. There were 14 releases in Georgia, 13 of Pseudoscymus tsugae and one of Scymnus sinvanodulus. Six of the releases were in conjunction with a study by Chris Asaro, University of Georgia. The Scymnus sinvanodulus release was in conjunction with Dr. Montgomery, USFS Northeast Forest Experiment Station.

Areas were picked for released based upon adequate adelgid populations being at levels to support the feeding of the predator insects, as well as relative position and importance of each Hemlock stand to be protected. These predator insects are being reared at Clemson University and the lab is primarily funded through the U.S. Forest Service.

Education/Outreach

During the 2003-2004 season, the GFC met with numerous interested agencies and organizations, introducing them to the HWA situation in Georgia and instructing them on the identification of HWA and reporting procedures. He was often able to meet with whole teams of agency people by getting on the agendas of regional or district meetings. This turned out to be very useful. He also received many reports of HWA infestations from USFS, Georgia Forestry Commission, Georgia State Park and Georgia DNR personnel as well as members of several organizations.