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Midge Tracker Maps Available

Farmers can track the emergence of wheat midge daily in their area by using an innovative online map provided by the Canadian Wheat Board (CWB).

The maps are now being regularly posted on the CWB website. During the peak of the pest threat, new maps and commentary by CWB agronomist Mike Grenier will be posted every day at

“Using localized weather information from our WeatherBug network, we have created pest emergence models that farmers have found very useful in their attempts to manage the risk,” Grenier said, noting that cool weather this spring has delayed crop and midge emergence this year by up to two weeks later than normal.

“Wheat growers, depending where they farm, should start checking their fields next week to decide whether midge-control pesticides are necessary. Control measures are most critical between the heading and flowering stages. Our map is designed to alert farmers when they should intensify their scouting for this pest.”

Grasshopper resource information and hatching models have also been posted on the CWB website. The grasshopper models were created by Dan Johnson of the University of Lethbridge using weather data and support from the CWB.

The midge map tool was devised by the CWB using data from Prairie weather stations – including the CWB’s on-farm WeatherBug network and pest modelling information available from Agriculture and Agri-Food Canada.

The daily maps provided by the CWB are colour coded with growing degree days that indicate midge development stages.

Midge is one of the most damaging insect pests for wheat growers in Canada. In the last two years, it was a major downgrading factor at harvest. The insect is responsible for millions of dollars in damage to crops from yield loss and lower end-use quality. While the threat has been reduced this year, farmers should still be vigilant in assessing their own risk.

The maps are the only daily information source on wheat midge that is available to all wheat farmers online. Going forward, the tool will be refined and extended to other pests of concern to wheat and barley producers.

Farmers can bookmark the map page on their home computers or hand-held devices and get a quick snapshot each day of how midge is progressing in their own area.

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