The starry sky beetle, or Asian longhorned beetle, is a pest that made its way from China and Korea to the American continent via the shipping of solid-wood packaging materials like palettes and crates. The invasive exotic insect attacks and kills a large number of hardwood species in North America and Central Europe. Since it has no natural enemy outside Asia, it constitutes a serious threat for urban and natural forests. The beetle can generate significant losses for the forestry industry and for maple producers.
How do we identify it?
This beetle in the Cerambycidae family (Anoplophora glabripennis) measures between 20 and 35 mm in length. It is noteworthy for its black antennae with white bands, longer than the body. Its black elytra (wing covers) each display about twenty irregular white spots. Their black feet have a blue-grey sheen.
From 1996 to 2002, populations were discovered in a number of American towns. In 2003, one of them was detected in an industrial park in the Greater Toronto area. It was eradicated, but ten years later a citizen of Mississauga, in the Toronto suburbs, identified another insect. The Canadian Food Inspection Agency (CFIA) confirmed the presence of the Asian longhorned beetle, and felled the infected trees. To this point, the insect is yet to be reported in Québec, but we have to keep an eye out for it.
Characteristic features have been identified on healthy and vulnerable tree species. The longhorned beetle primarily targets maples, on which it can complete its life cycle. But it can just as easily attack poplars, willows, birch and elm.
The female lays individual eggs that resemble small kernels of rice in the upper part of the host tree’s trunk or on the main branches. The young larvae bore galleries under the bark, on the surface of the sapwood, then tunnel to the heartwood as they feed. The whitish pupae, 30 to 33 mm in length, transform into adults and emerge from the tree through a hole 6 to 12 mm in diameter.
When the species is discovered, it is a matter of urgency to determine the extent of the infested area and to quickly establish measures for eradicating the pest in order to limit its spread. Specialized inspectors seek out the presence of adults during their flight period or visible signs and symptoms of attacks on trees.
What do we do?
Everyone can take part in measures to control the Asian longhorned beetle by looking for adult exit holes and laying sites on at-risk tree species. At the Frédéric Back Tree Pavilion, educators provide information on the Asian longhorned beetle, and simulation sites have been created by CFIA personnel. Any sign of the insect’s presence should be reported to that agency by calling 1 800 442-2342.
If it crosses our borders, the fight against this pest is likely to be very difficult. Every step should be taken to prevent its introduction, since affected trees have to be cut down, shredded and burned. As is the case with many environmental issues, participation of the public plays an important role in prevention.
Visuals 4 and 5
Signs and symptoms
Visible signs on the bark: egg niches, sawdust from boring, damage associated with adult feeding or exit holes
Symptoms: foaming sap, grooves in the bark, branch mortality or death of host