Saving the Hemlocks, one beetle at a time.
Predator Beetle Lab
The Roots of the Beetle Lab
During a field botany class a few years ago, a seed was planted in Dr. Robert Fuller’s head (Associate Professor and Environmental Leadership Center Director). The instructor of the class, Mark Warren, owner of the Medicine Bow outdoor school, was expressing the value of hemlock trees to the entire ecosystem and the grave risk they face from the hemlock woolly adelgid (HWA). The seed started germinating as he learned about the efforts to control this noxious pest locally by Young Harris College, Clemson University, and UGA. These labs have been working with imported beetles that prey on the HWA and Robert felt NGCSU should help fight in this battle too. Fortunately, this notion was allowed to sprout this time, where others have had theirs trampled in the past, and two people stepped in to help nurture his idea. First, Dr. Mike Bodri, Dean of the School of Science and Health Professions, offered his support and bountiful expertise. Secondly, Representative Amos Amerson was able to obtain ample funding to hire a full-time lab coordinator and support the lab in terms of materials and supplies to get the lab up and running. Soon members of the community stepped up and provided nutrients to Robert’s blossoming idea in terms of funding and donations. Three local nonprofit organizations, The Lumpkin Coalition, Upper Chattahoochee Riverkeepers, and Georgia Trout Unlimited, bestowed upon us much needed monetary donations and local residents have donated refrigerators, 5-gallon buckets, and their time.
The seed that was planted in Robert’s head was the tragic decline of the Eastern and Carolina hemlock trees due to the hemlock woolly adelgid (HWA). In the early 1920’s HWA was discovered in the western United States, thought to have been brought over in nursery stock. However, the Western and Mountain hemlocks seem to have the same tolerance for these pests as do the native Asian hemlocks where HWA is originally found. It was in the mid 1950’s that the HWA showed up in Virginia and has posed a threat to the Eastern and Carolina hemlocks which are susceptible to the HWA feeding. Almost the entire range of the Eastern hemlock and all of the Carolina hemlocks are under attack by this invasive species as it now is found as far north as Maine, west as eastern Tennessee, and south to northern Georgia. HWA can be commonly seen as white fluffs on the branches due to the cottony secretions they cover themselves with. This small purplish aphid-like insect feeds on the hemlock trees, piercing the bark and sucking the nutrients out, killing a tree in as little as 4 years. Since there are no native predators to the HWA, alternative methods like the use of biological controls and insecticides, are needed in order to control and stop it. Biological controls that have been identified and released throughout the infested areas of the U.S. include small beetles from Asia, Sasajiscymnus tsugae and Scymnus species, and British Columbia, Laricobius nigrinus, which have been found to feed primarily on the HWA. The NGCSU lab is working with S. tsugae, a poppy-seed sized black lady beetle that is native to Japan.
The mission of the NGCSU predator beetle lab is to rear S. tsugae for release in the local forests. The hemlock woolly adelgid has reached the Dahlonega area within the past few years. It’s no longer a bedtime story to remind little trees of the dangers to the North of them and how good they have it here. It is during these winter months that a “crawler” stage emerges and is spread by birds, animals, and humans moving through the forest picking up these unwanted hitchhikers. Another fact that helps the HWA spread rapidly is that they are all females and reproduce asexually, requiring no males to produce offspring. This catastrophic explosion of the HWA is why we need these predator beetle labs and releases into the forests. While managed insecticide use can help privately owned trees, it isn’t applicable for forest use and could possibly lead to other vectors to move in. Having a biological control that only feeds on these adelgids will help control the population once we get enough out there. The creation of this lab, the efforts from its workers and volunteers, and the increase of knowledge through the community will all aid in this battle against the hemlock woolly adelgid.
Come show your support every first full weekend in November at Hemlock Fest !