Hope for HemlocksPosted by | 07.27.2018
By Frances Figart
The Smokies’ forests help to provide clean air and clean water and support healthy wildlife inside the park and out. One of the most important of our tree species, eastern hemlock, has been under attack for several decades now from a non-native insect.
Jesse Webster is an NPS forester in the vegetation branch who has been coordinating the park’s hemlock conservation program for 15 years. He will speak on “Problems and Solutions with our Hemlocks” at 1 p.m. Friday, August 17, as part of Discover Life in America’s Science at Sugarlands series.
FF: What are the main challenges your team is facing?
JW: Eastern hemlock, an ecological foundation species in the eastern forest, is being driven to extinction by a non-native insect, hemlock woolly adelgid (A. tsugae). HWA is originally from Japan and made its way to eastern hemlock on horticultural plants. There are no native controls of HWA so it is able to reproduce exponentially—and hemlock cannot tolerate these numbers. The hemlock program’s main focus is an integrated pest management approach to control of HWA and thus conservation of hemlock on the landscape.
FF: Do you partner with other organizations in the study and management of hemlocks?
JW: Yes. There are universities up and down the East Coast that have been researching HWA and hemlock for the past 20 years. There is a national hemlock managers’ team that I am a part of that meets to discuss the latest science and operational techniques to control HWA. The park utilizes peer-reviewed scientific research to help steer our decisions on management in the park. There are many species associated with hemlock, and the work of Discover Life in America and the All Taxa Biodiversity Inventory has helped us to identify, inventory and study these.
FF: Is the science related to hemlock management changing?
JW: The biological controls that we are releasing to achieve a natural predator-prey balance have been established. Now it's just a matter of understanding what they are doing on the landscape and to what extent they are starting to control HWA in its different life stages.
FF: What is the outlook for the future? Will HWA be the next chestnut blight?
JW: Without intervention, hemlock will go extinct on the landscape in the Smokies within the next 40 years. With help from GSMA, Friends of the Smokies and the US Forest Service, the park has done a tremendous amount to help the hemlock. But more can be done and 40 years from now we don't want to say, ‘I wish we had done more.’ This will not be the next chestnut blight.
FF: What, if anything, can the public or park visitor do to aid in your work?
JW: The most important thing the public can do is to remain informed about forest insects and disease. These non-native forest pests have caused havoc in the park in the past with the chestnut blight and now the emerald ash borer. We don't need more of these. Don't move firewood or bring firewood into the park; this introduces all kinds of issues. Support park partners like GSMA so this work can continue.
Copyright August 2017