Asian Longhorned Beetle (ALB)

The Asian longhorned beetle (Anoplophora glabripennis), or ALB, is an invasive wood-boring insect that feeds on a variety of hardwoods including maple, birch, elm, ash, poplar, horsechestnut, and willow. ALB threatens the health of New York's hardwood forests and negatively impacts agriculture and tourism.

Description

ALB are approximately 1.5 inches long and shiny black, with white spots on their wing cases. They have black and white antennae that can be up to twice as long as their body.

ALB fact sheet (PDF)

Signs Of An Infestation

Trees being attacked by ALB often have wilted leaves and canopy dieback, but these symptoms can be caused by many different factors and should not be used on their own as signs of ALB infestation. The main signs to look for include:

1. Round exit holes that are ⅜ to ½ inches wide and at least an inch deep, created by  adults emerging from trees beginning in late July.
2. Round, ½-inch wide depressions (egg-laying sites) in the outer bark.
3. Sap oozing from egg-laying sites and exit holes.
4. Sawdust, or frass, collecting at the base of the tree or on branches.

Females often chew depressions in the bark where they deposit one to two eggs at a time, laying up to 60 eggs on average. After they hatch, the larvae bore into the tree and begin feeding on the living tissue just underneath the bark, which disrupts the nutrient and water flow within the tree. The larvae then continue burrowing deep into the heartwood where they feed until they are ready to pupate. Repeated attacks from scores of larvae, generation after generation, eventually girdle the tree and kill it. Tree death usually occurs 7-9 years after the initial infestation, depending on site conditions and the tree's overall health.

Females often chew depressions in the bark where they deposit one to two eggs at a time, laying up to 60 eggs on average. After they hatch, the larvae bore into the tree and begin feeding on the living tissue just underneath the bark, which disrupts the nutrient and water flow within the tree. The larvae then continue burrowing deep into the heartwood where they feed until they are ready to pupate. Repeated attacks from scores of larvae, generation after generation, eventually girdle the tree and kill it. Tree death usually occurs 7-9 years after the initial infestation, depending on site conditions and the tree's overall health.

Lookalikes

There are several native species that look similar to ALB. In New York State, one of the most common lookalikes is the whitespotted pine sawyer (Monochamus scutellatus).

• The whitespotted pine sawyer has a distinctive white spot at the top of where its wing covers meet, while ALB does not.
• ALB has white markings on the wing covers and antennae that are much more visible than on the whitespotted pine sawyer.

View the ALB lookalikes poster (PDF) for a side-by-side comparison of ALB and whitespotted pine sawyer, as well as several other native lookalikes.

Habitat and Distribution

ALB was first found infesting Norway maple trees in Brooklyn in 1996. Larvae and pupae likely hitchhiked from China in wooden packing material and the adult beetles emerged after the materials reached the New York Harbor. Additional infestations were later discovered in Manhattan, Queens, Staten Island, Islip, and central Long Island. To date, the Manhattan, eastern Queens, Staten Island, and Islip infestation sites have been eradicated. The largest infestation of ALB near New York State is in Worchester, MA and as of 2022, has a quarantine zone of over 100 miles. Visit the USDA ALB- Massachusetts webpage for more information.

Impacts

Since maples are a preferred host for ALB, the spread of the beetle into the rest of the state would mean devastating impacts to the maple syrup industry through the loss of healthy sugar bush. Maples are also a valuable hardwood for furniture, flooring, and other uses. Larval galleries through the heartwood may degrade the wood enough to make it useless for milling, costing the forest products industry billions of dollars. The larval galleries also compromise the structural integrity of the tree, resulting in falling limbs and trunks under heavy rain, snow, or wind pressure. Removing these hazard trees in parks and towns would be expensive and have serious impacts on property values and tourism. Maples are also some of the most abundant trees in New York’s forests, and their loss would threaten the resilience, health, and biodiversity of our forest ecosystems.

Management

• The NYS Department of Agriculture and Markets has taken the lead on surveying for infested trees, tree removal, and tree treatment to eradicate the ALB populations in New York City and on Long Island.
• International standards have been set that require wooden packing materials to be chemically treated or kiln dried to help stop new introductions from occurring.
• Quarantines have been established around infested areas to prevent the movement of infested materials.

How You Can Help

• Follow the NYS firewood regulation, which limits untreated firewood movement to no more than 50 miles.
• Obey the rules of the ALB quarantines, which prevent firewood and any regulated materials from leaving those areas. Visit the NYS Agriculture and Markets website for more information.
• If you have a swimming pool, you can participate in the ALB Pool Survey. Whenever you clean your pool, check your filter and skimmers for anything that resembles ALB. Send a photo of what you find to [email protected].

If you believe you have found ALB:

• Take pictures of the infestation signs as described above (include something for scale such as a coin or ruler);
• Note the location (intersecting roads, landmarks or GPS coordinates); then
• Submit a report to DEC’s Forest Health Reporting Form; OR
• Email DEC Forest Health at [email protected]; OR
• Call the ALB tip line at 1-866-702-9938; OR
• Report the infestation to iMapInvasives.