A pest that attacks trees is making a breakthrough in Quebec.
The zigzag elm sawfly was discovered in Sainte-Martine in July. It was a first in North America, reported “Our land” October 16. A citizen scientist reported it to Inaturalist.ca. The Canadian Food Inspection Agency (CFIA) confirmed its presence in Quebec in August. The insect has since been identified in Saint-Pie and Saint-Amable.
He is originally from Asia. The source of its introduction into Quebec is unknown, says the CFIA.
Its larva feeds on elm leaves and can cause serious damage to trees.
The species is considered invasive because it is parthenogenetic, that is, the female reproduces on its own. “No male is known,” CFIA said. And it produces up to 4-6 generations per year.
The zigzag sawfly lays in the jagged edge of elm leaves. After hatching, the larvae eat the entire leaf except the midrib.
Adults are tiny, shiny 6-7mm black wasps, describes the Canadian Food Inspection Agency. It can therefore disperse by flying.
The Agency encourages the public to submit samples of any suspected pests on elms to a local CFIA office. Suspicious observations can also be reported online. “This information will help assess the extent of the infested area and the threat posed by this pest and will help guide the next steps for Canada,” says the CFIA.