> Home | Alerts archive | Asian longhorned beetle
Invasives Alert!

Anoplophora glabripennis (Motchulsky)
(Asian longhorned beetle)

Summary: Insect invader increasing range
Two live adult Asian longhorned beetles (ALB) were found outside of a warehouse in Sacramento County on June 16, 2005.

The beetles are suspected hitchhikers in a shipment from China containing solid wood packing material. After confirmation by California Department of Agriculture (CDFA) experts, the warehouse and contents were fumigated. Outside, traps were set up and trees within a 9-mile radius of the warehouse were visually inspected (in a 1/4 mile radius using Forest Service smokejumpers). Two other warehouses receiving similar shipments (in Lancaster and San Diego, CA) are also being monitored. CDFA has followed up on places where product from these warehouses were sold. CDFA is working closely with the company owning the warehouse, the United States Department of Agriculture (USDA), the Sacramento County Agricultural Commissioners office and the Forest Service to prevent the establishment of this beetle in California (Hooper, personal communication, 2005).

The warehouse where the beetles were observed and the two other warehouses in southern California will continue to be monitored until 2008, even if no other beetles are detected. Potted trees (highly favorable host trees -- maples in this case) will be placed around the warehouse in Sacramento to detect live beetles that may have become established in the surrounding area. Next spring (2006), trees surrounding the warehouse will be preventatively treated with imidacloprid, a systemic insecticide that has been used successfully in the eastern U.S. to combat ALB. In addition, mailers asking the public to keep a lookout for the beetle will be sent out to nearby residences (Hooper, personal communication, 2005). Adults are very conspicuous and emerge from trees during the mid-spring to summer months. In California, if you see an adult beetle (catch it if you can and place it in a glass or plastic container), call 1-800-491-1899.

Description: known invader sighted in new areas
(Click on thumbnail images for a closer view)


Nightmare fodder

Adult I

Adult II

Life stages


Tree holes

Risk map


During removal


Asian longhorned beetle adults are bullet-shaped, 2.5-3.8cm in length and 0.7-1.2cm wide. The elytra (hard wing covers) are shiny black in color with irregular, white spots (up to 20 in number and sometimes yellowish in color). The long antennae are banded black and white and can reach 5-7.6cm in length and are typically 1.5 times the body length in males and 1.3 times the body length in females. The beetle's legs are bluish-white in color, especially on the upper surface (1,2,3). The larvae and pupae are not typically seen because they reside inside the tree. The biology is more extensively covered in Morisawa (2000).

Scientific and Common Names:
Anoplophora glabripennis (Motchulsky) (syn. Anoplophora nobilis) is commonly called the Asian longhorned beetle or starry sky beetle. In Germany it is known as the Asiatischer laubholzkäfer and in France as longicorne Asiatique (3).

The Agricultural Plant Health Inspection Service (APHIS) states that ALB's establishment in the U.S. could, "cause more damage than Dutch elm disease, chestnut blight, and gypsy moths combined." Tree mortality can occur quickly in infested areas (3-5 years). In China, poplar plantations are heavily damaged by this beetle (40% of the plantations, 2.3 million ha) (3). In the U.S., host trees favored by ALB include maples, elm, willows and horsechestnut (4). Healthy trees, as well as stressed trees, are attractive to ALB adults (Haack, 1997). Older larvae tunnel deep within the tree and cause limb breakage and tree mortality (Cavey et al., 1998). Infested trees pose a threat by possible personal injury and property damage. Nationally, the potential impact of ALB could be a decrease of 34.9% of canopy cover in urban areas. Urban tree mortality is estimated at 30.3% (1.2 billion trees) and valued at $669 billion (Nowak et al., 2001). It is estimated that ALB establishment could cost the lumber, maple syrup, nursery and tourist industry over $41 billion (4). Unfortunately, removing trees is the control method used to reduce ALB populations and prevent its spread. In U.S. cities where ALB has established over 10,000 infested trees have been cut down (Campbell, 2004).

Currently, ALB has only been found in urban areas and it is unknown how much damage could be caused if populations move to wildlands. One impact could be changes in dominant species composition of hardwood forests, especially in those forests composed mainly of maple and poplar (USDA APHIS & Forest Service, 2000 cited in Campbell, 2004). In the Northwest, populations of maples (Acer macrophyllum and A. circinatum), Populus spp., willows (Salix lasiolepis, S. laevigata, S. scouleriana, and S. sitchensis), birches (Betula papyrifera and B. occidentalis), sycamores (e.g. Platanus racemosa), and ashes (e.g. Fraxinus latifolia) are susceptible (5,6). Many hardwood forests in Canada are also susceptible (USDA APHIS & Forest Service, 2000, cited in Campbell, 2004). Tree mortality caused by ALB would impact insect and wildlife populations (e.g. birds) that rely on them throughout the west. In addition to causing tree mortality, established populations of ALB could increase fire damage and lead to erosion problems in forests (Hooper, personal communication, 2005).

Native Range:
ALB is native to Asia (Japan, Korea, and southern China) (1).

Range As An Invader:
In the U.S., the beetle has been detected inside warehouses in 14 states (Washington, California, Wisconsin, Illinois, Texas, Michigan, Indiana, Ohio, New York, Pennsylvania, North and South Carolina, Florida and New Jersey) and is established in live trees in New York, Illinois, and most recently New Jersey (4). The beetle has also invaded Britain and Austria (3).

Methods of Dispersal:
The main pathway of introduction has been in shipments containing solid wood packing material. Shipments of nursery plants may also play a role in dispersal. Locally, dispersal can be through moving infested firewood, containers, pallets, and dunnage. Adult beetles may hitchhike on vehicles and can fly to new areas (3). It is believed that adults are capable of flying up to 1000m. In a scientific study, adult beetles that were released were found to have moved 106.3m on average (Nowak et al., 2001).

Currently, the best management practice to control ALB populations is to remove the whole tree and chip and/or burn it. Systemic insecticides injected into trees such as imidacloprid prevents the further spread of ALB and does decrease populations (4). Observed tree infestations in New York, Illinois and New Jersey are decreasing each year due to these control tactics.

Entomopathogenic fungi are being studied. Adult longevity was reduced when beetles were caged with bands impregnated with an entomopathogenic fungus in China (Dubois et al., 2004). The search for natural enemies in China have resulted in 2 parasitoids in quarantine. Efficacy and mass rearing have been accomplished, however, non-target studies have yet to be conducted (3).

Monitoring for beetle infestations is through visual inspection of trees. The presence of emergence holes (9.5mm diameter, perfectly round holes), sap, frass, and oviposition sites (females chew a dime-sized shallow depression in the bark before ovipositing eggs (4)), usually indicates an infested tree. Pheromones and bait techniques have not been developed (3). Host resistant trees are currently being researched (3).

To prevent further invasion, APHIS published a ruling effective September 16, 2005 requiring all shipments with wood packaging to be treated (heat or fumigation with methyl bromide) and marked with the location of treatment (designated country code) (4).

If you suspect a beetle to be the dreaded Asian longhorned beetle, place the beetle in a container (glass or plastic - the beetle can chew through plastic bags) and contact your state department of agriculture:

California - CDFA Asian Longhorn Beetle Hotline - (800) 491-1899
Oregon - Oregon Department of Agriculture - (503) 986-4636 or 1-800-525-0137
Washington -- Washington State Department of Agriculture, Pest Program - (360) 586-8456

Cavey, J.F., E.R. Hoebeke, S. Passoa, and S.W. Lingafelter. 1998. A new exotic threat to North American hardwood forests: an asian longhorned beetle, Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae). I. Larval description and diagnosis. Proc. Entomol. Soc. Wash. 100(2): 373-381.
Campbell, F. 2004. Gallery of Pests: Recently introduced exotic forest insects -- Asian longhorned beetle -- Anoplophora glabripennis. http://tncinvasives.ucdavis.edu
Dubois, T., A.E. Hajek, H. Jiafu and Z. Li. 2004. Evaluating the efficiency of entomopathogenic fungi against the longhorned beetle, Anoplophora glabripennis (Coleoptera: Cerambycidae), by using cages in the field.
Haack, R.A., K.R. Law, V.C. Mastro, H.S. Ossenbruggen, and B.J. Raimo. 1997. New York's Battle with the Asian Long-Horned Beetle. Journal of Forestry 95(12): 11-15.
Hooper, John. August 2005, personal communication. Program Supervisor, Pest Detection/Emergency Projects, California Department of Food and Agriculture.
Morisawa, T. 2000. Pest Notes: Asian longhorned beetle -- Anoplophora glabripennis. http://tncinvasives.ucdavis.edu
Nowak, D.J., J.E. Pasek, R.A. Sequeira, D.E. Crane and V.C. Mastro. 2001. Potential effect of Anoplophora glabripennis (Coleoptera: Cerambycidae) on Urban Trees in the United States. Journal of Economic Entomology 94(1): 116-122.

1. http://www.cdfa.ca.gov/phpps/ppd/Entomology/Coleoptera/Asian_Longhorn_Beetle.html
2. http://www.uvm.edu/albeetle/
3. http://www.issg.org/database/species/ecology.asp?si=111&fr=1&sts=
4. http://www.aphis.usda.gov/lpa/issues/alb/
5. http://egov.oregon.gov/ODA/PLANT/ippm_alb.shtml
6. http://plants.usda.gov/

--Tunyalee Martin/Invasive Species Team; August 2005

Updated September 2005
©The Nature Conservancy, 2000