Burns Lake residents have noticed strange leaf markings lately. The markings are caused by the aspen leaf miner (Phyllocnistis populiella), a transcontinental pest of trembling or small tooth aspen.
“I’ve seen the aspen leaf miner in my yard and all over town,” said Burns Lake resident Walt van der Kamp. “Most people I talk to have also noticed them.”
According to Greig Bethel, Public Affairs Officer for the ministry of forests, lands and natural resource operations, the aspen leaf miner has been very common in Burns Lake over the past five years.
Bethel said the ministry hasn’t taken any preventive or control measures because there is no commercial market for trembling aspen, and the trees seem to survive the attacks.
“There are no risks to people, and usually the trees recover from the attack by producing more foliage,” he said.
The larvae mine the leaf contents but leave the upper and lower cuticle in place. There is one generation a year with adults overwintering in fallen leaves. Adults emerge, mate, and feed for approximately two weeks in early spring. They can often be seen resting on the sides of homes, windows and cars.
The aspen leaf miner is commonly found in Alaska, but sometimes the insect reaches outbreak proportions in western North America. According to the United States department of agriculture, an outbreak of the aspen leaf miner has been occurring in Alaska since 2000. Infestations were noted along the Alaska Highway in Canada as early as the 1950s. Outbreaks of aspen leaf miner rarely occur in eastern North America.
There are no effective control measures for large scale outbreaks of aspen leaf miner. Keeping trees in good health through fertilizing, watering, proper planting and pruning techniques, can help reduce the impacts of insect pests in general.