Additional Emerald Ash Borer found in Shenandoah National Park
Shenandoah National Park staff has confirmed the existence of additional emerald ash borer beetles (EAB) in the park. Sixty five adult EAB beetles were caught in an EAB surveillance trap near the park’s northern boundary and the town of front royal. Due to the large number of EAB beetles found in a single trap, the level of EAB infestation in this area is assumed to be fairly high. This new location of EAB is 4.5 miles north of the park’s initial EAB detection in August 2013 in the Dickey Ridge Picnic Area (a single EAB).
The emerald ash borer is a half inch-long metallic green beetle that lays eggs on the bark of ash trees. After hatching, the EAB larvae burrow under the bark and create feeding tunnels that cut off nutrient and water flow to the tree. As a result, ash trees typically die within three to five years. EAB was accidentally introduced to North America from Asia and was first discovered in southeast Michigan in 2002. Since its introduction, EAB has spread to 23 states and two Canadian provinces killing over 50 million ash trees.
Ash trees are a significant component of Shenandoah National Park’s ecosystems. Five percent of the trees in the park are ash. However, ash trees are widespread across the park, and occur in 16 of the park’s 34 vegetation communities. Collectively, these ash containing communities make up 65% of the park’s forest (126,883 acres). If EAB becomes well established in the park, it could lead to large-scale ash mortality and cause impacts similar to what was seen when the park’s eastern hemlock trees were killed by hemlock woolly adelgid.
Since the EAB is a nonnative pest, the park is mandated to minimize its impacts on native ash trees. In April 2013, due to the close proximity of EAB to the park at the time, staff began conducting preventive EAB pesticide treatments on ash groves in developed areas and select sensitive plant communities in the northern third of the park. Park staff plans to continue and expand this project in spring 2015. The project goals are to reduce hazard ash tree formation in developed areas and to preserve a portion of the park’s ash trees until approved bio-controls (e.g. parasitic wasps) become available. Park staff is planning to treat 1200-1500 ash trees per year. Complete eradication of EAB is not currently feasible, but park managers are taking these actions to maintain public safety, and to protect ash trees where possible.
EAB and other tree pests can be transported via firewood. Park regulations prohibit bringing firewood into Shenandoah from outside areas. For more information about firewood regulations at Shenandoah, visit our website at: http://www.nps.gov/shen/