Controlling Mosquitoes & Forest Tent Caterpillars

Winnipeg’s Insect Management Areas (IMAs)

Winnipeg’s neighborhoods have been grouped into 51 Insect Management Areas. Just type in your address and find out what insect management area you reside in.

Mosquito Control 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.

Nuisance Mosquito Fogging Program 2016:  During a Fogging program, the IMAs to be fogged will be announced at least 8 hours in advance of fogging operations. Weather permitting, fogging would occur daily from 9:30pm to 6:30am.

The City of Winnipeg controls adult mosquitoes along streets and lanes, City parks, golf courses, cemeteries and rights-of-way within the City boundaries using Malathion® ULV (Malathion® Label / Malathion® MSDS) for ultra low volume applications (ULV) and Permanone® (Permanone® Label / Permanone® MSDS (permethrin) for residual treatments.

Forest Tent Caterpillars

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..

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.


Register for Notification

Citizens can register to receive notification of the City of Winnipeg’s Elm Bark Beetle Activities, Tree Pest Caterpillar Activities, Gypsy Moth Activities and Mosquito Fogging Activities . The notification will identify the area(s) of the City in which Insect Control Crews are intended to work – weather permitting.  Once registered, residents will receive automated phone or email notification for one or more of the Insect Control Activities they choose for notification.

For Notification By E-mail:   Citizens can enter their e-mail address and select their program of interest. Citizens can register for one or more notifications using the following links:

For Notification By Telephone:   Registrants must provide their name, the date, the address of their principle residence and one telephone number at which they want to be notified to:

Insect Control Branch,  3 Grey Street,  Winnipeg, Manitoba,  R2L 1V2
Fax: 311    Phone: 311 or 1-877-311-4WPG