West Virginia’s majestic hemlock trees are under attack by a tiny enemy. The Hemlock Woolly Adelgid (HWA) is an invasive species that traveled from Asia to the U.S. in the 1950’s on imported Christmas trees. As it’s name implies this insect is has a white, fuzzy appearance like a tiny puff of cotton.
These bugs suck sap from young twigs on hemlock trees causing the hemlock needles to dry out and drop. Tragically, this defoliation can cause the hemlock tree to die in only a few years.
What is the range of the HWA?
Lacking natural enemies in North America, HWA has spread throughout the eastern United States via wind, birds, mammals, human activities, and the transport of infected nursery stock. The Hemlock Wooly Adelgid is prevalent in about half of the hemlock range in the eastern U.S. and has killed about 90% of the hemlocks in Shenandoah National Park in Virginia.
Why are hemlocks so special?
The stakes are high: the hemlock tree provides habitat for dozens of mammals and birds. Arching over streams, it creates deep shade critical for the survival of trout and other fish. Some scientists think the hemlock is a so-called keystone species, holding up a whole ecosystem.
- Nearly 90 species of birds can be found in hemlock forests. Several species are significantly associated with hemlock forests, including the black-throated green warbler, Blackburnian warbler, and the Acadian flycatcher.
- A wide variety of aquatic species is more likely to be found in streams sheltered by hemlock than streams sheltered by hardwoods. For example, both brook trout populations and macroinvertebrate diversity are greater in hemlock streams.
What is Adventures On The Gorge doing about it?
To assist in the long-term preservation of the hemlock we are establishing our property, along the Mill Creek watershed and Tree Tops Canopy Tour in West Virginia, as a Hemlock Preservation Site. As such, our Canopy Tour staff will implement a long range treatment plan. Every hemlock over 6” in diameter has been surveyed and labeled for treatment.
The trees are treated using insecticides and predator beetles that munch on the HWA. The insecticide that we are using to treat our hemlocks is a neonicotinoids. This acts similar to nicotine in cigarettes by suppressing the bugs’ appetites and causing them to starve themselves to death.
A dollar from every canopy tour participant’s fee will be donated to a hemlock preservation fund to assist in the funding of this costly treatment plan and we will match those funds, dollar for dollar. Take a trip on TreeTops and you will officially become a tree-hugging hippie!
For more information on the Hemlock Woolly Adelgid problem in our US hemlock forests, visit the US Forest Service HWA Resource site.