Planting Promise for Hemlocks

Volunteers help plant insectary to raise predator beetles

A crew of volunteers and Forest Service researchers planted seedlings for an insectary where live predator beetles will be raised for biocontrol of hemlock woolly adelgid. Photo by U.S. Forest Service.
A crew of volunteers and Forest Service researchers planted seedlings for an insectary where live predator beetles will be raised to feed on hemlock woolly adelgids. Photo by U.S. Forest Service.

On August 3, 15 young volunteers and U.S. Forest Service researchers worked in the hot sun at the Bent Creek Experimental Forest near Asheville, North Carolina, planting eastern hemlock tree seedlings for a biocontrol insectary. Participants from Boy Scout Troop 91 were joined by friends and classmates from area schools and two parents in planting 88 trees on about an acre of land to rear Laricobius osakensis, a predator beetle that feeds on the hemlock woolly adelgid.

For over a decade now, the tiny nonnative hemlock woolly adelgid has laid waste to the hemlocks of southern Appalachia, turning the towering trees that serve as keystone species along mountain streams into gray ghosts. Efforts to keep hemlock trees alive and on the landscape include releasing biocontrol insects such as Laricobius beetles that feed almost exclusively on the adelgids, but there’s never enough of the predator beetles to go around. The insectary will provide an additional location to raise predator beetles to release on hemlock trees in high priority areas such as National Forests and other public lands.

This fall, researchers from the Forest Service Southern Research Station (SRS) plan to start introducing predator beetles onto infested hemlocks on the outskirts of the insectary. “Predator populations in the insectary should increase slowly over time,” says Bud Mayfield, project leader of the SRS Insects, Diseases, and Invasive Plants unit and leader of the project. “After a few years, we hope to have sufficient numbers of Laricobius beetles to collect and transfer them to other areas.”

“It would have taken us days to plant these trees without the help of these young men,” says Mayfield. “They helped us get these trees in the ground quickly, and we all had fun and learned from each other.”

For more information, email Bud Mayfield at amayfield02@fs.fed.us.

Read more about preparing the site for planting on the Field Notes blog.

 

Access the latest publications by SRS scientists.

Subscribe to our newsletter!

Receive weekly updates