State Senator Andy Dinniman with members of the New Century Club during a tree planting ceremony in Hoopes Park. Pictured (from left to right) are Nancy Berg, Pat Horrocks, John Snook, Dinniman and West Chester Borough Urban Forester Denise Dunn-Kesterson.
WEST CHESTER — With an invasive beetle species threatening ash trees across the state and the nation, West Chester is taking the lead to ensure that it remains “Tree City, USA.”
Thanks to a partnership between the Pennsylvania Department of Conservation and Natural Resources (DCNR), West Chester University, and borough officials, West Chester recently served as a test site for the “Emerald Ash Borer Management Plan for Pennsylvania Communities” – a program that has now expanded to 10 communities statewide.
During a recent Arbor Day celebration at Hoopes Park, state Senator Andy Dinniman took the opportunity to recognize the highly successful program, which now serves as a model for communities and municipalities across the Commonwealth.
“For 26 consecutive years, West Chester has received the Tree City USA Award for its commitment to maintaining the health, beauty and diversity of trees throughout our parks, neighborhoods and the downtown,” Dinniman, who serves on the Senate Environmental Resources and Energy Committee, said. “I want to thank all the staff and volunteers for their ongoing efforts in safeguarding our trees and preventing invasive species like the emerald ash borer from jeopardizing our rich natural heritage.”
The emerald ash borer is a half-inch long metallic green beetle that is wreaking havoc on ash trees in towns, parks and forests across the nation. The borer, which originates from Asia, first appeared in southeastern Michigan in 2002 and since then has been detected in 25 states and destroyed more than 40 million ash trees. It has been detected in 56 of Pennsylvania’s 67 counties.
“If you don’t have it already, it is coming and it will kill 99 percent of your ash trees,” Dr. Donald Eggen, DCNR’s Forest Health Manager said. “If you have a lot of ash trees and do absolutely nothing that is the most costly because they will all die at once. Especially if you have big trees as they are expensive to take down.”
The larva of the ash borer feeds exclusively on ash trees in North America. Host species in Pennsylvania include green ash, white ash, black ash, blue ash and pumpkin ash. The adult borer typically emerges between April and July, depositing eggs in bark crevices. The eggs hatch and the larvae bore into the tree to feed on the living tissue just below the bark surface. The larval feeding results in the tree being girdled, preventing the movement of nutrients and water between the roots and the tree crown. The infestation usually kills ash trees in 3 to 4 years after being attacked.
“The emerald ash borer has not yet been detected in Chester County, but it is all around us,” said Kendra McMillin, a West Chester University graduate student who played a key role in launching the program. “We will fully expect it to already be here.”
That is why Eggen and McMillin, along with West Chester University professor Gerard Hertel; DCNR Forest Entomologist Houping Liu; and West Chester Borough Urban Forester Denise Dunn-Kesterson worked to implement the ash tree assessment and prevention program to protect ash trees in borough parks.
Beginning in 2013, the borough initiated the plan as a pilot program, in which ash trees in its three most heavily wooded parks – Hoopes, Marshall Square and Everhart – were evaluated, monitored and treated based on their prognosis.
About 100 high value ash trees in good health were proactively treated with an injectable systematic insecticide to ward off the borer.
As a result of its success, the West Chester program was awarded federal grant funding to continue its monitoring and prevention efforts.
McMillin said West Chester was ideally suited to be the program’s first site due to its comprehensive and up-to-date tree inventory.
“West Chester was really way ahead of the game in that sense because the tree inventory is a huge part of it. We had the knowledge of what trees we have and where they are,” she said. “For instance, we have a significant amount of mature ash trees in Hoopes Park. Can you imagine if those trees were infected and started coming down in three years?”
Both Eggen and McMillin also emphasized that studies have shown that monitoring, treatment and prevention programs are far more cost effective than the financial burden of paying for the removal of so many dead trees. Part of the reason is that while ash is a hardwood, a borer infection results in the ash tree and its branches becoming increasingly fragile and brittle, making it unsafe for an arborist to climb them during removal.
The goal is to save as many trees as possible and to prevent any potentially hazardous or dangerous situations, they said. Though the systemic insecticide injection is highly effective against the borer, once a tree is more than 30 percent in decline, it is beyond saving.
In addition, Eggen noted that it can be difficult to predict where major borer infestations will take place.
“You never know when the infestation is going to happen. We don’t have a good survey tool for detecting low populations,” he said. “It can be percolating and then it appears and it’s here. They also start up high in the trees and by the time they get down to the bottom it’s too late.”
Dinniman said he would continue to work in the legislature to ensure that West Chester and Chester County municipalities have access to the support and resources they need to conserve their trees, parks, natural places and open spaces for generations to come.
“West Chester borough and everyone involved in initiating this program deserves our appreciation for their practical and hands-on approach to managing and preparing for the coming threat of the emerald ash borer,” Dinniman said. “It’s a testament to their diligent and thoughtful work that the program has been adopted as a model for other communities across Pennsylvania.”
For more information, call Senator Dinniman’s office at 610-692-2112 or e-mail acirucci@pasenate.com.
