Insects, Pests & Diseases

Insects of Concern to Brookline
Asian Longhorned Beetle
The Asian Longhorned Beetle (ALB) was discovered near the Boston / Brookline boundary on July 3, 2010, and is still a significant concern for Brookline. The ALB poses a significant threat to many hardwood tree species.

Residents are encouraged to look for the ALB and report any sightings. Visit asianlonghornedbeetle.com or www.massnrc.org/pests or call the ALB hotline at 866-702-9938 for more information, or to report possible sightings.
Asian Longhorned Beetle
The ALB has previously been discovered in the New York city area, the Chicago area, New Jersey, Ontario, and most recently in 2008 in the Worcester, Massachusetts area. The beetle infects many deciduous tree species, and damages the trees when larvae bore into the heartwood, eventually leading to the death of the tree. Infested trees show characteristic egg laying sites on the bark, round exit holes where adults have emerged, and frass or sawdust-like material on the branches or ground below.

Tree Removal

Currently, the only way to eradicate the beetles when trees are already infested, is removal of the infested trees. However, the U.S. Department of Agriculture (USDA) is undertaking research on controlling or preventing infestations through systemic injection of insecticides. There is significant concern that the beetle may continue to spread and drastically damage our urban forest, as well as trees throughout New England.

Additional Information

If you find a beetle that may be the ALB or a tree with damage that is consistent with this beetle, please report as noted above or by contacting the Parks and Open Space Division immediately. For current updates, photographs and other information on the ALB visit the ALB website, UMass Extension website, USDA website, or Massachusetts Introduced Pests Outreach Project.
Emerald Ash Borer
The Emerald Ash Borer has been found in Massachusetts and is a significant concern for Brookline's trees.  As of 2015, there is a statewide quarantine restricting movement of hardwood firewood and ash nursery stock and lumber outside the regulated area.

Residents are encouraged to look for the EAB and report any sightings. Visit stopthebeetle.info or www.massnrc.org/pests for more information, including quarantine details, or to report possible sightings.
Emerald Ash Borer

The Emerald Ash Borer was first discovered in southeastern Michigan in 2002 and has since spread across much of the midwestern United States. The beetle has only been observed feeding on ash trees, where larvae tunnel through the wood, leading to death of branches and eventually the entire tree. Infested trees may exhibit vertical splits in the bark above feeding sites, and D-shaped holes where adults have emerged.

Additional Information
If you find a beetle that may be the Emerald Ash Borer or a tree with damage that is consistent with this beetle, please report as noted above or by contacting the Parks and Open Space Division immediately. For current updates, photographs and other information on the Emerald Ash Borer, visit the Emerald Ash Borer website, Stop the Beetle website, U.S. Department of Agriculture website, or Massachusetts Introduced Pests Outreach Project.

Present in Brookline Already
Winter Moth
Winter Moth, a defoliating caterpillar, is an insect pest whose population is growing exponentially in the northeast, after its initial identification in 2003 in eastern Massachusetts. The insect detrimentally affects all deciduous trees and shrubs where it lays its eggs, when caterpillars feed on buds, leaves and flowers. Adult moths are visible and active during the early winter months. In accordance with the Park Division's proper integrated pest management approach, either B.t.k. or Conserve is used to control the Winter Moth in a few select areas of town. The town will continue to monitor the insect's population and impact. For current updates, photographs and other information on the Winter Moth, visit UMass Extension.
Winter moth caterpillar
Hemlock Woolly Adelgid
Hemlock Woolly Adelgid is an aphid-like insect that attacks hemlocks. The adelgid was discovered in Massachusetts in 1988, and has led to the death of many of the hemlocks that once flourished in this area. It is believed to be present in most hemlocks at this point. The insect feeds on the sap of the hemlock, leading to galls and/or woolly masses on the needles and stems.

The Parks Division closely monitors Brookline's hemlocks, and those that need treatment are sprayed or injected with a dormant horticultural oil as part of an integrated pest management approach. For current updates, photographs and other information on the Hemlock Woolly Adelgid, visit UMass Extension.
Hemlock Wooly Adelgid
How You Can Help

  • Keep an eye out for current risks to Brookline by inspecting trees on and around your property for signs of the Asian Longhorned Beetle or the Emerald Ash Borer. If you spot suspicious insects or tree damage, please contact the Parks and Open Space Division.
  • Do not transport wood great distances, particularly out of the Asian Longhorned Beetle regulated areas in Boston / Brookline and surrounding Worcester. Buy firewood close to where it will be burned. Campfires are not allowed in Brookline's parks, but many state parks and campgrounds that allow fires will not allow people to bring in their own firewood, because of the risks of introducing insects and pests.
  • Inform friends, family and neighbors of the risks our trees face from invasive insects, pests, and diseases.
Photos courtesy of R. Childs / Umass Extension