Asian Long-horned Beetle
Aspen, Birch, common Horsechesnut, Elm, Hackberry, Maple, Mountain Ash, Poplar and Willow
Appearance and Life Cycle
The adult Asian long-horned beetle emerges from the infested tree in May. Their emergence holes are about 10-15 mm in diameter. The adult beetle is 2.5-4 centimeters (cm) long. They are shiny black with white spots and have long, white and black banded antennas. Most of the time, the newly emerged adults will remain on the same host tree, but they can fly up to several hundred metres in search of another host tree. Adults are active for mating and egg-laying purposes from early summer to late fall.
Adult females live approximately 40 days and lay about 25-40 eggs. The females will dig an oval groove about 15-20 millimeters (mm) long in the bark of the tree in which they will lay a single egg that is 5-7 mm long. Either the egg, larvae or pupae will overwinter in the tree. Usually the egg will hatch in about 2 weeks, after which the larvae will burrow into the tree. Larvae are creamy-white with a brown head, segmented and can reach a length of up to 50 mm. They create long, winding tunnels and feed in the innerwood of the tree. The pupae are orange and have a mature length of 32 mm.
Currently, the Asian long-horned beetle has only been found in eastern Canada and parts of the United States. The insect might become a threat to the prairie provinces in the future. For a distribution map, please visit www.inspection.gc.ca. Adult emergence holes leave a wound about 15-20 mm either on the trunk, branches or exposed roots. The oral grooves for the eggs leave a wound 15-20 mm long which can drip a frothy sap. Insects such as butterflies, bees and wasps will be attracted to the dripping sap. Sawdust and frass can be seen around the tree base, in cracks in the bark and in the branch crotches. Other signs of infestation include yellowing of foliage and pre-mature leaf drop. Injury caused by the Asian long-horned beetle also makes trees more susceptible to other insects and diseases. The damage caused by the Asian long-horned beetle and other factors can kill the tree.
There are no chemicals registered for control of the Asian long-horned beetle. Infested trees should be removed and burned before the adults emerge and spread to new areas. If you suspect that there is Asian long-horned beetle in your area, please notify the Canadian Food Inspection Agency.
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