Boring threat to our street trees munches ever closer; destructive beetles found in Essex County

State officials say emerald ash borers were discovered last month in Essex County.

The invasive, destructive pests, native to China, had previously been detected only in remote Dalton in the western part of the state.

It was first discovered in North America in 2002, in the Detroit, Michigan area. Unlike many other invasive beetles, EAB kills ash trees quickly, within just 3-5 years, because it bores directly under the bark and disrupts the tree’s conductive system. Since its discovery in North America, it has killed millions of ash trees and has caused billions of dollars in economic loss nationwide.

Unlike the western part of the state, we don't have many ash trees in our forests. But, state officials say, ash trees are popular for street planting around here.

State officials say containing the tiny beasts will likely involve creation of a quarantine zone, similar, if less stringent, to that established in Jamaica Plain and part of Roslindale after Asian Longhorned Beetles were discovered on the grounds of Faulkner Hospital in 2010:

Officials say residents should learn the signs of emerald-ash-borer infestation, including:

• Tiny, D-shaped exit holes in the bark of ash trees, dieback in the upper third of the tree canopy, and sprouting of branches just below this dead area.
• Extra attention paid by woodpeckers to ash trees in the winter. "Fresh, light-colored wood pecks stand out against the darker bark of the tree. Severe woodpecker activity at the base of the canopy or on the main stems may indicate possible EAB infestation and should be reported to state forest health personnel immediately."
• The borers themselves: Small, metallic green beeetles (seven could fit on the head of a penny).

Photo by the USDA. Posted under this Creative Commons license.