Hemlock Wooly Adelgid - Identification and Control
Monday June 30, 2008
Eastern and Carolina hemlocks are now under attack and in the early stages of being decimated by an aphid-like insect called the hemlock wooly adelgid (HWA). Although the outcome looks grim in a growing number of locations, there are things being done to control the pest in a forest situation. One promising control is a Wooly Adelgid eater called HWA predator beetle.
Hundreds of thousand of ladybug-like beetles have been released in the Great Smoky Mountain National Park and surrounding national forests to help control the hemlock wooly adelgid. The Park Service is presently more concerned about the loss of hemlock and the spread of wooly aphids than the consequences of releasing it's exotic beetle predator. The adelgids of the Adelges species have tragically killed millions of trees at high elevations, not only in the eastern United States but out west as well. The balsam wooly adelgid, introduced from Europe, is a major killer of Fraser firs.
For Hemlocks in yards there are other options. Wooly adelgids can be controlled during late October as the second generation begins to develop with insecticidal soaps. Horticultural oil can be applied during winter and before new growth emerges in the spring but spraying trees can be very costly. The Bayer Advanced company promotes their Tree & Shrub Insect Control as an annual systemic treatment for individual trees.
Wooly Hemlock Adelgid, Kim Nix Photo
Comments
Is there any commercial source for the ladybird beetles for homeowners? We have a large stand of native hemlocks here which are already infested and I would like to do what I can to possibly save them.
I would be very interested in locating a source where I could purchase a quantity of beetles for assisting in controlling the adelgid population on the hemlocks on my property. Any pointers are greatly appreciated.