Save the Hemlocks
Hemlock Woolly Adelgid
Eastern hemlock trees are some of the largest and most common trees in the Great Smoky Mountains.Unfortunately, they are under attack from a non-native insect called the hemlock woolly adelgid. Without successful intervention, the hemlock woolly adelgid is likely to kill most of the hemlock trees in the park. Called the “redwood of the east,” eastern hemlocks (Tsuga canadensis) can grow more than 150 feet tall on trunks measuring six feet in diameter. Some hemlocks in the park are over 500 years old. Over 800 acres of old-growth hemlock trees grow in the Smokies—more than in any other national park. Younger hemlock forests cover an additional 90,000 acres of land in the park. Originally discovered here in 2002, adelgid infestations have now spread throughout the park’s hemlock forests. In some areas infested trees have already begun to die.
Since its arrival in the U.S. in the 1920s the hemlock woolly adelgid has rapidly colonized parts of New England and the Mid-Atlantic States, where it feeds on eastern hemlock. In the south, it also feeds on Carolina hemlock. The insect is easily dispersed by birds and wind but travels most rapidly as a hitchhiker on infested horticultural material.The hemlock woolly adelgid has infested hemlocks on the Blue Ridge Parkway for about 10 years and in Shenandoah National Park since the late 1980s. In these areas as many as 80 percent of the hemlocks have died due to infestation.
Hemlocks play an important role by providing deep shade along creeks, maintaining cool micro-climates critical to survival of trout and other cold water species. The impact of widespread loss of hemlock could trigger changes more significant as those that followed the demise of the American Chestnut in the 1930s and 40s.
The hemlock woolly adelgid is an aphid-like insect that covers itself with awhite, waxy “wool” which acts as a protective coating for the insect. Adelgid infestations are easily recognizable by the appearance of tiny “cotton balls” at the base of hemlock needles.The “wool” is most conspicuous on the undersides of branches from fall through spring. (reprinted from http://www.nps.gov)
Plan of Action
Go Outdoors USA is currently monitoring, tagging and treating hemlocks in the two areas we have adopted( Three forks and Dicks Creek). We also work in conjunction with Save Georgia Hemlocks http://www.savegeorgiashemlocks.org/ , and the USFS on treating hemlocks in other areas of the Nation Forests.