The City of Montreal is taking a new approach to controlling the prolific pests by introducing a predator — the parasitic wasp.
“If we see good results we will recommend this procedure to other boroughs and maybe reduce the amount of pesticide used in the Montreal territory,” Maryse Barrette, a researcher with the City of Montreal's environmental science department, told Mike Finnerty on CBC’s Daybreak Montreal.
Barrette is part of the pilot project in a small pocket of NDG where about 12,000 parasitic wasps ordered from a commercial producer in Europe were released across 12 linden trees last August.
The parasitic wasp is not one that stings people and buzzes around sweet drinks on restaurant terrasses. Barrette says the parasitic wasp is smaller, commonly used in agriculture, and not aggressive towards humans.
“The wasps that we release are a ‘good’ wasp,” said Barrette. “We call it a wasp, but wasps contain millions of species.”
To the aphids, the wasp is not so kind.
“They lay the eggs inside the aphids. The eggs hatch and the larvae eat the aphid alive,” said Barrette.
A gruesome fate for the aphids, but Barrette says the wasps could be a sustainable solution for controlling the pest.
“When it’s well done, normally we minimize the risk, and it’s already used in apple orchards, for example,” said Barrette.
Barrette says the team is still working in the field and has not yet analyzed the findings.
However, she hopes the results are good for the trees, and bad for the aphids.