Penn State DuBois students gain hands-on experience protecting the PA State Tree
DuBOIS, Pa .– The Eastern Hemlock was officially named the Pennsylvania State Tree in 1931 for a variety of reasons, from its significant presence in Commonwealth forests to the resources it provided to the early settlers who built cabins. Today, however, hemlock is attacked by an invasive insect species known as the hemlock woolly aphid, which is native to Asia. Penn State DuBois Biology 220 students are helping conservation professionals at the Pennsylvania Department of Conservation and Natural Resources (DCNR) fight this threat.
BIO 220 students recently visited the Bilger’s Rocks Recreation Area near Grampian, Pa., Where they helped forestry professionals treat the trees with an insecticide to protect them from the insect.
The hemlock woolly aphid is classified by DCNR as a serious threat to the state’s hemlock forests, with the pest confirmed in 64 of the state’s 67 counties. DCNR Service forester Rick Conrad explained, “This is a serious threat. In North Carolina, the insect has destroyed thousands of acres of hemlock forest. We are concerned that it could happen here.
The insect causes damage to the tree by piercing the needles of the tree and feeding on the nutrient-rich fluids within. An infested tree can be identified by yellowing needles and cotton-like egg masses on the underside of the needles. These infested trees often die.
A significant loss of hemlock in Pennsylvania would be devastating for the environment, foresters say. Trees are a vital source of shelter and food for many forms of wildlife. In addition, the woolly aphid threatens another icon of Pennsylvania, the state fish, the brook trout. The shade provided by the branches of the hemlock prevents the sun from hitting the waterways, maintaining the cool water temperature necessary for the growth of native brook trout.
But DCNR retaliates with a Hemlock conservation plan. Part of this plan is to treat the trees with an insecticide. Forest professionals mix the insecticide solution and use a special tool, such as a giant syringe, to inject it into the soil around the base of a tree. Quickly, the team, including students from Penn State DuBois, treated 79 trees on the last visit to Bilger’s Rocks.
“We inject soil at the base of the tree. The tree absorbs it and passes it on to the insects that feed on it, ”said Tim Tomon, forest health specialist with DCNR’s Bureau of Forestry. “It can be good for four to five years.”
Biology professor Lola Smith began getting her students to participate in this project in 2019. COVID restrictions were preventing students from participating in 2020, but Smith now plans to make it an annual activity. She said that between 2019 and 2021, students helped treat nearly 200 hemlocks. Since many students are enrolled in the Wildlife Technology program, this gives them a glimpse of what they might expect if they embark on a career in environmental conservation. Smith explained, “It gives them hands-on experience, as well as experience in forest ecology and health. They can also see what it entails for jobs in forestry and other careers that may be of interest to them.
Wildlife technology student Zane Grimes agreed that these exercises are a valuable learning opportunity. He said: “I think the experience outside of the classroom adds so much more than just attending a conference. I am a tactile learner so it works for me.
Another wildlife technology student, Sam Miron, said she appreciates the chance to meet people who work in fields that interest her. “
Smith said another benefit of taking on these out-of-class projects is that students also learn the value of service. She noted, “Students give back to their community and help the environment. They help these professionals deal with a very real environmental threat.
According to DCNR, the hemlock woolly aphid was first discovered in the United States in Virginia over 50 years ago. It has since spread to 17 states, with widespread hemlock mortality reported in Tennessee, North Carolina, West Virginia, Virginia, Pennsylvania, Connecticut and New Jersey.
Additional information on the hemlock woolly aphid, the DCNR conservation plan and advice for owners are available on the website DCNR website.