The Emerald Ash Borer has been spreading since it was first found in the Arnold Arboretum in Jamaica Plain in 2014. The invasive beetle has been identified in the neighborhoods of Allston-Brighton, Dorchester, Fenway-Kenmore, Hyde Park, Jamaica Plain, Roslindale, Roxbury, Mattapan, and West Roxbury, as well as the Arboretum, Franklin Park and the Muddy River area. This Borer lays eggs on the bark of ash trees and upon hatching, the larvae burrow deeper in the tree, killing it. The pest only feeds on ash trees.
Ash trees in Jamaica Plain and around the City are beginning to show outward signs of infestation, which include D-shaped exit holes in the bark of ash trees, ”blonding” from woodpecker feeding, dieback in the upper third of the tree canopy, and sprouting at the base of the trunk.
Last week Acting Mayor Kim Janey and the Boston Parks and Recreation Department announced measures being taken to slow the spread and protect Boston’s public street trees from the Emerald Ash Borer.
On Oct. 15 Janey and the Parks Department unveiled how the City will manage the infestation by treating healthy trees on public property to prevent infection and removing trees that are dead, dying, or significantly damaged.
Janey said several hundred street trees will be removed this winter while the trees are dormant, and preventative injections will begin next spring when healthy trees are becoming more active. Sites where trees have been removed will be prioritized for new tree plantings in the next planting season. Managing the Emerald Ash Borer infestation in Boston will take place over several years.
“Dead, dying, and damaged trees pose a significant public health and safety threat to Boston’s communities,” said Janey. “The City Arborist is currently working to determine which public street trees have been infested with the Emerald Ash Borer. It’s crucial that we save as many trees as possible with smart management decisions to protect our City’s green spaces for generations to come.”
Head of Horticulture at the Arnold Arboretum and member of the Community Advisory Board for the Urban Forest Plan, Andrew Gapinski, said since its introduction into the U.S. Midwest in the 1990’s, the emerald ash borer has killed millions of natural and cultivated ash trees.
“Spreading to Massachusetts in 2012, it was first detected in Boston here at the Arnold Arboretum through a rigorous monitoring program in partnership with the DCR and the City,” said Gapinski. “The City’s Urban Forest Plan aims to diversify, expand the tree canopy, and prepare for the challenges of tomorrow—a key step toward a more resilient and sustainable urban forest,” said “The emerald ash borer is here to stay, and best management practices of surveying the City’s ash trees for signs of the beetle, removal and replacement of trees in decline, and treatment of trees in good health is essential to saving as many ash trees as possible. EAB is just one of many introduced pests that have devastating effects on our forests, landscapes, and communities – and it certainly will not be the last.”
The City’s Urban Forest Plan’s initial phase, a comprehensive tree inventory, was completed in September and revealed that Boston is home to approximately 1,817 public street ash trees, which represent about 4.3% of the city’s total street tree population. The Plan’s recommendations will also include increased funding and staffing for tree care and to more effectively respond to invasive insects like Emerald Ash Borer.
“While tree removals are always challenging to witness, they are necessary to protect healthy trees and to stop the spread of Emerald Ash Borer,” said Parks Commissioner Ryan Woods. “Dead trees, with their brittle wood, quickly become a safety hazard.”
Chief of Environment, Energy, and Open Space Reverend Mariama White-Hammond said understanding canopy loss is the first step in addressing issues affecting Boston’s trees—like climate change, development, pests, and disease—and how those factors intersect.
“That’s why the Parks Department is developing a road map to powerful, equity-centered policy changes that will preserve and expand our tree canopy—the City’s first Urban Forest Plan,” she said.
The Parks Department cares for public street trees and park trees. The city is encouraging residents that believe they have seen an infested ash tree on a public street or park, contact 311. Private property owners should learn to recognize ash trees, check for signs of infestation, and contact a certified arborist for preventative treatments.