Professors and researchers at Camcore, a non-profit international conservation program within North Carolina State University’s Department of Forestry and Environmental Resources, are working on a project to preserve the Carolina and eastern varieties of hemlock.

An exotic insect, Adelges tsugae, also known as the hemlock wooly adelgid, has become a serious threat to the survival of the Carolina and eastern hemlock populations, according to Robert Jetton, a research associate at Camcore.

“The insect was introduced from Japan, we think, sometime in the 1950s,” Jetton said. “It didn’t become a problem until the 1980s when it made its way into the Appalachian region. For the trees that are currently infected with the insect, [the outlook] is not good.”

Jetton explained that the United States Forest Service is attempting to combat the insect through biological control methods, the introduction of predators of the hemlock wooly adelgid and chemical pesticides.

“Both biological control and chemical control have a lot of promise, but it takes time — we’re kind of the insurance policy,” Jetton said.

William Dvorak, director of Camcore, said the U. S. Forest Service approached Camcore with the hemlock problem.

“The thought was,” Dvorak said, “what can Camcore do to help the Forest Service?”

Camcore’s project aims to preserve the hemlock’s genetic material through the storage of seeds and through ex-situ — or off-site — cultivation.

“We make sure we have genetic material in a safe place,” Dvorak said.

He explained that the motivation for projects such as this one is to prevent a situation like the one that occurred in the early 1900s with the American chestnut.

The chestnut blight rapidly decimated the population of the American chestnut, and the preservation of the chestnut’s genetic material is uncertain.

Andy Whittier, a research associate at Camcore, said the hemlock plays an important role in the ecosystem as a riparian species, but he said the amount of travel involved in the project makes it hard to involve undergraduate students.

According to Jetton, the project hasn’t been suitable for graduate students either with most of their projects happening during the semester.

“We haven’t had the funding [to hire students to work part-time],” Jetton said.

Dvorak and Jetton both said they hope that adelgid resistant genotypes can be developed through breeding.

“That’s great challenge,” Dvorak said. “There are a lot of things on the research end that we need to get working on.”

Dvorak explained the insect does not affect the hemlocks native to China and Japan, where the adelgid originated.

Cross-breeding these resistant species with the Carolina Hemlock and Eastern Hemlock species may produce varieties of hemlock that preserve the Carolina and Eastern hemlock’s genetic material while enabling them to withstand the adelgid.

However, there is still more work ahead to preserve the hemlock before breeding programs will be developed, according to Jetton.

Jetton described the project in three phases.

First, in 2003, researchers collected seeds from the Carolina hemlock. In 2005, researchers collected seeds from the southern portion of the Eastern hemlock?s range. The third phase will begin in 2009 when researchers gather seeds from trees in the northern part of the Eastern hemlock?s range.

Jetton said the seed collection for the Carolina Hemlock went very well, but recent drought conditions across the southeast made collecting Eastern Hemlock seeds difficult. He hopes the rainfall this past year will aid researchers as they complete the second phase of collection this year.

Once the seeds are collected, some will be held in storage and others will be cultivated ex-situ in locations with hemlock-compatible climates and no evidence of the hemlock wooly adelgid. According to Jetton, the selected sites are located in Chile, Brazil and the Ozark mountains in Arkansas.

“The really promising area is Chile” Jetton said, citing how similar the latitude of the Chilean planting site is with the Pacific Northwest, another area where hemlock trees grow natively.

Currently, hemlock seedlings are growing in nurseries in Arkansas, Chile and Brazil. Some young hemlock trees have already been planted at the cultivation site in Chile.

“They’re doing very well,” Jetton said. ?It?s a very good climate match.”

Jetton added that the possibility of the hemlocks themselves becoming an exotic invasive species in Chile or Brazil is not a concern.

Hemlocks are slow growing and have very specific environmental requirements. Since hemlock trees are not a pioneer species, successful growth is the challenge, not containment.

“The chances that hemlock could escape cultivation are very minor,” Jetton said.

As an industrial cooperative Camcore has partnerships with companies all around the world, Jetton said. Forestry companies will be growing the hemlocks in partnership with Camcore, on land that they privately own.

Though little research has been done regarding the cultivation of hemlocks, the forestry companies are doing well, according to Jetton. He adds that the foresters have a great deal of experience that they have been able to apply to this project.

Camcore researchers are also working on a small cultivation site in Ashe County, N.C.

Whittier said developments at this site will enable Camcore foresters to make helpful recommendations to foresters at the sites in Chile, Brazil, and Arkansas, and as the U.S. Forest Service continues its efforts to fight the hemlock wooly adelgid, Camcore will be working to guarantee a future for the hemlock.

“The forest service has done a great job leading the charge,” Dvorak said, “and we think that N.C. State has done a lot to complement their efforts.”