Saving Our Hemlocks From HWA, Thursday September 18, 2008

Save Our Hemlocks Logo

Hemlock Forest2


Photo Courtesy of Back 40 Films

Dear Colleague,

On Thursday, September 18, Valent U.S.A. Corporation, Appalachian Arborists, The Eastern Native Tree Society and Back 40 Films will be co-sponsoring a Hemlock Woolly Adelgid (HWA) meeting entitled "Saving Our Hemlocks from HWA: An Urgent Call to Action." We cordially invite you to attend this meeting.   We are inviting a diverse array of individuals and groups who have a strong interest in the preservation of hemlocks from HWA. These include arborists, forest and park services, forestry commissions, university scientists, land trusts, conservation groups, business leaders, media and legislators. The goal of this meeting will be to help maximize the survival of hemlocks growing on public and private lands in the United States , especially in the Southern Appalachians .


This meeting will have several objectives including:

  • Summarize the latest research regarding the use of neonicotinoid insecticides for control of HWA
  • Propose a near-term management plan for HWA affecting high value hemlock stands and individual trees
  • Highlight a documentary that is being developed to raise awareness of the HWA crisis: "The Vanishing Hemlock: A Race Against Time"
  • Identify obstacles that are preventing more aggressive treatment of hemlocks
  • Tour first hand a forested area that has been heavily impacted by HWA
  • Motivate interested parties to collaborate in the effort to preserve as many hemlocks as possible from HWA

Meeting at a Glance


Date:        September 18, 2008


Time:        9:00 AM - 1:00 PM:   Presentations and Discussion

                 1:00 PM - 4:00 PM:   Bus Tour to Cataloochee Valley , GSMNP

Location: Grove Park Inn, Asheville, NC

Meeting Room:  Hoover Suite


Transportation to and from Cataloochee Valley will be provided, along with a boxed lunch.   


About Hemlock Woolly Adelgid and Various Treatments


As you are aware, the HWA has caused devastating losses to Eastern and Carolina hemlocks in the Southern Appalachians , and the rate of loss has been accelerated by the on-going drought.  This invasive pest has already killed large areas of some of our most valuable old growth Eastern hemlock forests. The magnitude of HWA infestation has now reached a point where it threatens to cause the functional extinction of the already rare Carolina Hemlock and the collapse of the entire hemlock-dominated ecosystem in the Southeastern U.S.   Never before in modern times has the Eastern forest experienced the loss of a keystone species with no ecological surrogate.
The long-term survival of our hemlock forests will ultimately depend upon the introduction and successful establishment of natural enemies of HWA. In the last several years, there has been a sustained and significant research effort to identify, mass rear and release predatory beetles that feed on HWA. There is some indication that beetles have begun to establish, but to date, these natural enemies have not prevented the continued decline and death of hemlocks due to HWA infestation. The research community remains hopeful that given time, natural enemies will establish to levels that will maintain HWA at a level that hemlocks can tolerate.  But for this to occur, we must first buy time for our hemlocks, and the most viable short-term solution is the judicious application of insecticides.
It is not practical to treat all hemlock trees with insecticides, but individual trees and high priority hemlock stands can be saved from HWA.  In the past several years, many thousands of hemlocks in the Southern Appalachians have been soil treated with the neonicotinoid imidacloprid (Merit). Soil application of Merit has generally been effective when applied before infestation or early in the infestation process, and one application can provide several years of control. However, a significant percentage of remaining hemlocks in the Southeast are now heavily infested with HWA and in serious decline. Imidacloprid is not an ideal treatment for heavily infested trees because it can take 1-2 years to provide control. Recently, a more systemic and rapid acting neonicotinoid has been identified - dinotefuran (Safari). When applied to the soil or as a trunk spray, Safari can provide control within only a few weeks after application, and has been used to rescue many severely infested hemlock trees that were previously considered unsalvageable.  


All methods of HWA management will be discussed at this meeting, as well as steps we all may take to help address this devastating pest. A preliminary agenda for this meeting is included in the RSVP form linked below.   


If you plan to attend, please download the RSVP form linked below and email to Meg Brodman at or fax to 901-524-5578 by no later than Friday, August 15th.



For questions about the meeting, please contact Joe Chamberlin at

 We hope to see you there.


 Will Blozan

President, Appalachian Arborists and Eastern Native Tree Society


Joe Chamberlin, Ph.D.

Regional Development Manager, Valent U.S.A. Corporation


David Huff , M. Ed., M.A.

Executive Producer, Back 40 Films



This event is sponsored by:


ENTS                         VH Logo                       Appalachian Arborists                            VPP Logo             

Eastern Native Tree Society     The Vanishing Hemlock: A Race Against Time          Appalachian Arborists                         Valent Professional Products