The emerald ash borer (EAB) (Agrilus planipennis) is an invasive beetle from Asia that infests and kills North American ash species (Fraxinus sp.) including green, white, black and blue ash. All of New York's native ash trees are susceptible to EAB.
The emerald ash borer is a very small but very destructive beetle. It has four life stages: adult, egg, larva and pupa. The adult beetle has a shiny emerald green body with a coppery red or purple abdomen. Adult beetles leave distinctive D-shaped exit holes in the outer bark of the branches and the trunk. Adults are roughly 3/8 to 5/8 inch long with metallic green wing covers and a coppery red or purple abdomen. The adults may be seen from late May through early September but are most common in June and July.
Signs of Infestation
An ash tree infested with EAB may show the following signs:
- "blonding" or large strips of bark falling off due to increased woodpecker activity;
- tree canopy dieback, yellowing, and browning of leaves;
- distinctive D-shaped exit holes in the bark of the branches and the trunk left by adult beetles emerging from the tree; and
- S-shaped galleries under the bark, often seen when the tree's bark splits or falls off.
Most trees die within 2 to 4 years of becoming infested.
How EAB Spread
Most long-distance movement of EAB has been directly traced to ash firewood or ash nursery stock. Other untreated ash wood, wood chips greater than one inch, and ash product movement (logs, lumber, pallets, etc.) generally present lesser risks. Wood chips less than one inch or mulch are considered to pose little risk of movement. New York State currently has a regulation restricting the movement of firewood to protect our forests from invasive pests.
Adult EABs typically fly less than ½ mile from their emergence tree. Since EAB is widespread throughout New York State, the beetles flying from one place to another is not of great concern.
Distribution and Habitat
EAB was first discovered in New York State in 2009 and has been confirmed in all New York counties except: Essex, Hamilton, and Lewis.
DEC works with partners such as NYC Parks and Cornell Cooperative Extension to detect and confirm new infestations across the state.
Ash is a very common street tree in many New York communities. It was widely planted to replace native elms lost to Dutch elm disease. In Michigan, the first state in the U.S. infested with EAB, the greatest economic impact has been on communities faced with removal of thousands of dead ash on streets and in yards. Many of these dead trees pose significant public safety hazards and liability problems for municipalities and landowners.
Historically, ash has been a common and valuable forest species:
- Ash seeds are a food source for birds and mammals.
- Ash species (white, green and black) comprise almost 8% of all trees in NY State.
- Ash is a commercially-valuable species, and is used for baseball bats, flooring, furniture, lumber, and pallet manufacture.
- Black ash is also prized by Native American tribes, including the Akwesasne, for traditional basket making.
The insects below are often mistaken for emerald ash borer beetle.
While DEC is still collecting new EAB location information, we are not actively managing infestations.
New York has a regulation to restrict the movement of firewood of any tree species to within 50 miles of its source or origin. If you must move ash wood that is not firewood, be sure to follow DEC's guidelines on moving ash wood responsibly. The firewood regulation remains unchanged and in effect despite the changing or lifting of any EAB quarantines.
EAB is listed as a prohibited invasive species by 6 NYCRR Part 575. Under this regulation, no person shall sell, import, purchase, transport, introduce or propagate, or have the intent to take any of these actions on the regulated species, unless issued a permit by DEC for research, education, or other approved activity.
How You Can Help
If You Found EAB
If you confirm your tree is infested with EAB, you do not have to take it down unless the tree could pose a hazard by falling (check for nearby structures, roads, etc.). DEC can confirm if the signs of tree damage are from EAB and provide tree removal information, but unfortunately there are no DEC programs to assist landowners with tree removal. If you choose to have a tree removed, we suggest visiting our tips for selecting an arborist or tree service for guidance.
How to Report a New Infestation Location
If you think you have found EAB and are in Essex, Hamilton, or Lewis county:
- Take photos of the insect and/or signs of damage.
- Email photos and location information to us at [email protected].
- You may also call DEC's Forest Health Information line at 1-866-640-0652
- Don't Move Firewood - help protect our forests from invasive insects and diseases
- Multi-state website devoted to EAB information
- EAB Cost Calculator - Purdue University
- USDA APHIS EAB webpage - U.S. Department of Agriculture, Animal and Plant Health Inspection Service
- US Forest Service Northeast Research Station - EAB Research
- Time Magazine - DEC Forestry staff in Region 3 working on the Department's Slow Ash Mortality (SLAM) program to slow the spread of the destructive emerald ash borer
- USDA Animated Video - great for elementary aged children
- Watch a clip about emerald ash borer and check out other clips on DEC's YouTube Channel