Asbury Woods is preparing to cut 82 dead and dying ash trees along the boardwalk on the west side of Asbury Road. There are hundreds of ash trees across Asbury Woods 205 acres that have been infected with the Emerald ash borer, an invasive bark beetle that was first introduced to the U.S. in 2002 and made its way to Pennsylvania by 2007. The Emerald ash borer causes mortality in nearly 100% of large, over story ash trees that it infects. Over the past several years, Asbury Woods has been monitoring ash trees as they have been losing limbs and dying, but there is a significant concentration of them at the end of their life near the boardwalk that goes through the James Preserve along the Greenway trail on the west side of the property.
Dr. Chris Dolanc, Professor of Biology at Mercyhurst University and an Asbury Woods board member, notes, "Scientists are unsure of what the long-term impacts will be on our native forests as a result of this massive die-off of ash trees. My research plots at Asbury Woods monitor the yearly impacts of this pest. The wetland forest adjacent to the boardwalk is dominated by the endangered pumpkin ash, which is just as susceptible to emerald ash borer as other ash species. Most of the medium to large-sized trees in the area are now dead or dying. As they die, they become a hazard to passing trail users and must be cut down to minimize danger. The cutting process is designed to mimic natural processes as the trees will be left on-site so their nutrients can be returned to the forest ecosystem. Leaving trees on-site also reduces the transmission to other locations as living larvae and eggs are still present on those trees."
Dolanc continued, "Our research so far has shown that the smaller trees are more resistant to Emerald ash borer invasion. The forest is still full of healthy ash seedlings and saplings, so perhaps they can help the ash forest regenerate once the initial wave of invasion has passed."
In conjunction with Mark Spitulski of MKS Arborist Services, Dolanc and Asbury Woods grounds crews identified ash trees in the boardwalk's vicinity that were potential threats to trail users and marked them for cutting. Jennifer Farrar, Asbury Woods Executive Director, noted, "Active management of this threat to the forest and trail users is an essential part of what we do to balance our desire to nurture healthy forest ecosystems with the need to keep the property a safe place for visitors."
The tree work is expected to start the week of November 1. A section of the Greenway Trail will be closed to the public for several days to allow the work to take place and for any clean-up and repair that needs to happen before it can be safely reopened to the public. Visitors who wish to access Walnut Creek will need to enter the trail system via the Browns Farm trailhead on Sterrettania Road. Trails on the east side of Asbury Road surrounding the Andrew J. Conner Nature Center will remain open.