Winnipeg, MB - Today the City of Winnipeg's Insect Control Branch provided an update on the mosquito larviciding program and forest tent caterpillar program.
The Insect Control Branch continues an aggressive larviciding program and is reminding Winnipeggers to join the Agents of S.W.A.T. (Standing Water Action Team) to do their part and empty any standing water on their property.
With the recent significant rains over the last 14 days, the summer nuisance mosquito species have hatched in high numbers in standing water. With the forecast of continuing normal temperatures, the second generation of summer adult nuisance mosquitoes will begin to appear in the next 5 to 7 days, weather dependent.
“The Insect Control Branch will continue using all resources to check and treat approximately 31,000 hectares of potential larval development sites in Winnipeg and the surrounding 10 kilometre treatment area, to reduce the emergence of adult nuisance mosquitoes,” stated Ken Nawolsky, superintendent of insect control. “We are monitoring conditions on a daily basis, and are ready to implement the range of control measures available.”
The most recent city-wide New Jersey Light Trap count was 0. Currently, the Adulticiding Factor Analysis (AFA) rating is at Medium. The Insect Control Branch is closely monitoring the AFA conditions daily, and will adjust the level when the factors that make up the AFA change.
The Insect Control Branch is continuing its forest tent caterpillar control program. Tree spraying has been carried out in Insect Management Areas 43, 45, 48, 49, 59 and 51. Treatment in Insect Management Areas 23 and 24 are continuing and then will begin in Insect Management Areas 1 and 2.
“Treatment is expected to continue for approximately another 10 days at which point the forest tent caterpillars will stop feeding as they prepare for the next phase of their life cycle,” stated Nawolsky. “Around mid-June they will look for a place to pupate and will emerge as moths about two weeks later.”
Throughout the program, surveillance crews will continue to identify areas of the city where trees require treatment.
Forest tent caterpillar larvae typically feed on American Elm, Manitoba Maple, Green Ash, and ornamental trees.
A Public Service Announcement will be issued daily providing information on what areas of the city will be sprayed the following day. This announcement will also be posted at City of Winnipeg - Insect Control News/Public Notices. Until further notice, the forest tent caterpillar treatment program will occur nightly from 9:30 p.m. to 6:00 a.m., weather permitting.
Treatment will be conducted using Bacillus thuringiensis var. kurstaki (Btk), a biological, organic product which is sprayed from high pressure tree sprayers directly onto the foliage of the trees. Once Btk is ingested by forest tent caterpillars, they stop feeding and perish approximately two to three days later.