Winnipeg.ca-UD: Public Works: Insect Control Branch

Insect Information
Tree Pests - Asian Longhorn Beetle

What are Asian Longhorned Beetles?
Where do ALHB live?
What type of tree's do they destroy?
What do Asian Longhorned Beetles look like?
How do I know a tree is being attacked by the ALHB?
What is the lifecycle of the ALHB?
How does the beetle spread to other areas?
How can ALHB be controlled?

What are Asian Longhorned Beetles? Asian Longhorned Beetles (ALHB) are a serious pests of hardwood trees. Tunneling in the wood by the larvae can girdle tree stems and branches. Repeated attacks lead to dieback of the crown and eventually, death of the tree. Top of Page Where do ALHB live? They are native to Asia, but presently they are undergoing eradication efforts in New York City and Chicago areas. Top of Page What type of tree's do they destroy? Maple, popular, willow, birch, elm, ash, and horse chestnut. Top of Page
Adult Asian Longhorned Beetle	What do Asian Longhorn Beetles look like? The adult has a shiny black body (2 to 3.5 cm long) with white spots. Antennae are longer than the body with alternating black and white bands. Legs are black with pale bluish sections. Larvae and pupae are hidden inside the host tree within tunnels bored by the larvae. Top of Page
How do I know a tree is being attacked by the ALHB? Round holes in the bark approximately 1 cm across, bored by the emerging adult. Oval to round pits or niches in the bark made by the adult female to deposit her eggs. Sap that oozes from the egg laying pits as the larvae feed. Accumulation of sawdust (from the boring larvae) around the base of infested trees as well where stems and branches meet. Top of Page
Picture showing round holes in the bark bored by the emerging adults, as well the shallow niches in the bark excavated by the female to deposit her eggs.	Sap may ooze from the egg laying niches as the emerging larvae feed, especially in maples.	Sawdust may accumulate (from the boring larvae) around the base of infested trees as well where stems and branches meet.
What is the lifecycle of the ALHB? ALHB usually has one generation per year depending on the regional climate. Eggs as well as larva and pupa can overwinter. Overwintering larvae begin to feed in March and pupate in June with emergence of the adult from host trees in June or July, remaining active into October. Adults can be seen actively feeding and mating in the tree canopy during sunny days from 8:00 to 14:00. Adults will feed on leaf stalks, leaves, young bark or twigs. The female adult can produce approximately 25-32 eggs, which she lays in niches or pits she excavates in the bark. Top of Page How does the beetle spread to other areas? On its own, adults can fly hundreds of feet, which is increased when wind aided. More importantly people transporting infested firewood can unintentionally spread ALHB. Top of Page How can ALHB be controlled? The only means of control at the present time is to remove infested trees and destroy them by chipping or burning. As well, quarantine areas must be established to prevent the transport of infested firewood and/or wood products from infestation sites. Top of Page

Last update: 01/19/2009