Bertha armyworm 2020 mapfrom Alberta Agriculture

By Dori Modney with files and video from Alberta Agriculture

Alberta Bertha Armyworm 2020 survey and potential for 2021

Feb 2, 2021 | 5:23 PM

EDMONTON, AB. — Alberta Agriculture`s Bertha Armyworm (AKA – Mamestra configurata) monitoring program has been conducted since 1995, to help track the progression of the pest.

In 2020, 350 sites of pheromone-baited trap, supplied by the Prairie Pest Monitoring Network, were set up to monitor for bertha armyworm across Alberta, to help determine the density and distribution of moths.

Provincial government personnel, industry agronomists, applied research associations, agricultural fieldmen and cooperating growers maintain the pheromone trap network, to help facilitate Agriculture and Forestry in organizing a map with information on areas of the greatest concentration. It also organizes the network of pheromone traps and maintains the map and the web-based application.

Moth counts from the traps are submitted using a web-based application that can be accessed using a smart phone.

The findings in 2020, showed the bertha armyworm populations increased in many locations including in central Alberta and as far south as at the MD of Willow Creek.

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At this point, the trend indicates a bertha armyworm outbreak is possible or even likely in Southern Alberta and the Peace regions. The entire 2020 map can be viewed on the Alberta Agriculture website.

While weather and natural enemies (birds) tend to keep bertha armyworm populations in check parasite, snow coverage can also encourage over-wintering and increases populations. Conversely, minimal snow coverage can reduce overwintering.

In any event, larger populations would require insecticide applications when the larval numbers meet the economic threshold.

The objective of monitoring is to increase awareness for canola producers to the damage potential of bertha armyworm. Forecast maps DO NOT replace field scouting. No field should be treated for bertha armyworm without proper field scouting.

in 2013, Alberta Agriculture produced a short video on field scouting for bertha armyworm.

Also, experience from previous outbreaks has shown that adjacent fields, including those in Saskatchewan or even different parts of the same field,can have differing bertha armyworm numbers.

Producers growing peas and faba bean also need to pay close attention to the bertha monitoring system as bertha armyworm has been known to feed on both those crops.