Cleveland, TN – May 13, 2005 ... Maintaining healthy forests is a dynamic and challenging task. There are a number of forces that pose serious threats to the health of our forests. An invasive insect that is of great concern to resource managers in the Cherokee National Forest and surrounded forested areas is the Hemlock woolly adelgid.
Public information open houses are scheduled for May 23rd in Elizabethton and May 24th in Tellico Plains. The intent of the meetings will be to provide current information about the hemlock woolly adelgid (HWA) to land owners and to present an overview of the HWA project proposed for the Cherokee National Forest (see last paragraph for meeting details.)
This tiny insect species native to Asia, was accidentally introduced in the eastern United States in 1924. It has expanded its range into the Southern Appalachians dramatically over the last several years. Hemlock trees that are host to this insect are an important component of riparian (areas along streams, rivers and lakes) ecosystems, providing cooling shade for streams, contributing nutrients for streams through litterfall, and providing winter shelter for wildlife. Once infested by the woolly adelgid hemlocks are weakened, gradually lose their foliage, and are unable to refoliate or produce cones.
Cherokee National Forest Supervisor, Tom Speaks said, “A hemlock woolly adelgid (HWA) infestation is currently present in numerous parts of the National Forest. We have been monitoring the situation and taking actions to curtail the spread of this serious threat. Areas currently infested with the HWA are spread across the northern end of the Cherokee National Forest, with high concentrations in Carter and Unicoi Counties. Some infestations have also been detected in the Tellico Ranger District (Monroe County.) We are very concerned about what this could ultimately mean. We know that hemlocks are an important source of shade to mountain streams and to a number of public recreation areas.”
The loss of hemlocks will mean a loss of shade for streams and a loss of a major riparian component. Shade from hemlock trees helps provide cooler water temperatures. The loss of shade along streams will cause an increase in water temperature. A two to three degree rise in water temperature could be very detrimental to aquatic life, especially in trout streams.
In late 2002 a hemlock woolly adelgid (HWA) outbreak was discovered in Dennis Cove Campground, in the Watauga Ranger District. In July 2003 USDA Forest Service personnel treated the infested area with a soil-injected insecticide. At this time there are a significant number of areas known to be infested with the HWA spreading to new areas.
Hemlock woolly adelgid infestations are recognizable by tiny tufts of white, no larger than 1/8 inch at the base of the needles. The tufts are the protective covering for the tiny insects. Adelgids rob hemlocks of nutrient-rich sap. They also may release a toxin preventing new growth. Trees typically die three to seven years after infestation.
Ed Brown, a forester at the Cherokee National Forest said, “The adelgid has infested states from New England to Georgia. We are working closely with our Forest Health Protection field office in Asheville North Carolina to slow and reduce this serious threat. We are currently proposing treatments for the control of the non native insect, hemlock woolly adelgid (HWA), which is attacking eastern hemlock and Carolina hemlock trees. The proposed action would focus on protecting selected populations of both species of hemlock with two methods of suppression; 1) release of bio-control agents such as predator beetles and 2) the limited use of insecticides. The purpose would be to suppress some current infestations of HWA while helping to establish reproducing populations of predator beetles in selected areas. The long-term goal is to ensure eastern and Carolina hemlocks continue to be a part of the very diverse ecosystems found in the Cherokee National Forest.”
In 1992 entomologists found a natural predator beetle, Pseudoscymnus tsugae, to combat the woolly adelgid. Biological control could be critical to saving hemlocks in the Southern Appalachians. Likely areas for release of predator beetles are thick hemlock stands where infestation has not overstressed the trees and where there are enough adelgids for the beetles to feed on.
“Controlling this threat is going to be a challenge. We know the situation is critical and we have a lot of work to do. The key will be to treat as many areas as early as possible. Our goal is to save as many hemlocks as possible,” said Mr. Brown.
Public information open houses will be conducted by the USDA Forest Service and TDOA Division of Forestry on May 23, 2005 in Elizabethton at Sycamore Shoals State Park, and on May 24th, in Tellico Plains at the Tellico Community Center. The intent of the meetings is to provide current information about the hemlock woolly adelgid (HWA) to land owners and to present an overview of the HWA project proposed for the Cherokee National Forest. Both meetings will begin at 7 PM, with registration at 6:30 PM. The first portion of the meeting will consist of presentations on HWA background information, landowner information, and an overview of proposed actions for the Cherokee NF. This will be followed by an open forum to allow participants to ask questions and talk with various agency specialists one-on-one.