Loss of Hemlocks Threatens BSG Water Supply

Many Hemlocks Can Be Saved

Big Stone Gap town councilman Freddie Allison came to Dungannon last Friday hoping he would hear some good news about saving the giant hemlock trees at the Big Cherry Reservoir.

 He and other leaders from Virginia , Kentucky , Tennessee and North Carolina were invited to a conference sponsored by The Clinch Coalition to hear from experts who have been battling the dreaded hemlock woolly adelgid.

 “We must act fast” says Allison. “I went into the meeting not knowing for sure that we could save any of our hemlocks because of the high cost of treating them. Thanks to this convening, I now know that we can save most, if not all of the healthiest hemlocks if we work together before the infestation gets any worse.”

 Allison is very concerned about the survival of the hemlocks around the Big Cherry Reservoir because they are the main tree species in the four-mile-stretch between the lake and the intake at the water plant. 

 “If these hemlocks die, the water quality will be very much affected,” Allison adds.

“The cost of treating them now will be much lower than the cost of cleaning up dead trees or extending our intake up to the lake itself, which is not a viable option.”

 

Town Councilman Freddie Allison seated right listens to Rusty Rhea, USFS.

The leading hemlock woolly adelgid experts in the region presented information about the history of the invasion of this insect into the eastern United States and more recently into the Appalachian mountain forests. They brought information on what has been done to stop the infestation in other areas and ideas of what can be done in southwest Virginia and surrounding states.

According to Will Blozan, President of the Eastern Native Tree Society and co-owner of Appalachian Arborists out of Asheville , NC , “We have the advantage of the hard work of treatment in other areas.  We now know that:

• You can't save them all
• You can’t stop the spread
• You can save individual trees and forests
• Large, remote tracts can be preserved
• You have to act quickly and aggressively
• Monitoring with no action is a death sentence
• Apathy is a choice; in other words, death

 

Ron Bush, of the Clinch Ranger District, Jefferson National Forest told the audience that the insect was first discovered locally in August 2006 at the Flanagan Reservoir in Dickenson County . 

 In November of 2006 The Clinch Coalition began exploring and monitoring hemlock stands on the Clinch Ranger District and has found the wooly adelgid at several other locations, including Roaring Branch in Wise County and at Devil’s Fork and Hanging Rock in Scott County .

 “At this point” Bush said, “Virginia Tech has released some beetles on Devil's Fork and will do another release.  We hope to be able to do a chemical treatment by the fall.”

 Though beetles are being used in some places, they have not been found to be very affective. According to conference presenter Rusty Rhea, Forest Entomologist with the US Forest Service out of Asheville , N.C. “Soil injection of the chemical Imidacloprid is the most effective method of killing the insect. The cost has recently come down dramatically because the patent expired a couple years ago.”

 Jeremy Stout, Bristol ’s Steele Creek Nature Center Manager, noted that this chemical is based upon the naturally occurring pesticide nicotine. "Imidacloprid is the active ingredient in most flea medications," Stout said, adding that the chemical does not affect animals other than insects and zooplankton.

 Rhea went on to tell the audience that the “ecological effects of the Hemlock loss will be the most far reaching and significant.  The increase in stream temperature impacts insects which impacts trout and other aquatic life.  There are also some birds which nest and forage in hemlocks exclusively and there are no real substitute tree species.”

 Public land managers across the region are treating their hemlocks. 

 As for private landowners, the experts suggest the following:  

·        If you suspect that your hemlocks are infected with hemlock woolly adelgid, first look for fuzzy white masses on the undersides of the needles to determine whether the insects are present.

·        Landowners can treat infected trees using the soil drench method, which consists of pouring diluted Imidacloprid onto the soil.  Trees should be treated in spring or fall when the soil is moist but should not be treated if rain is expected for the next day.

For a landowner’s fact sheet on how to identify and treat the adelgid, visit The Clinch Coalition's website at www.clinchcoalition.net.