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Test your bertha armyworm identification and scouting skills with these 6 questions…
Bertha armyworm
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The most damaging of the 'green' worms is the bertha armyworm, which can be green, brown or black… -
The three most common pod munchers are bertha armyworm, diamondback moth larvae and lygus bugs. Hot spots can sometimes be isolated to specific fields, so check each field. Before spraying, make sure insects counts are at or above economic thresholds. Applications made when insect numbers are below thresholds will not provide a positive return on investment and can do unnecessary… -
A few hotspots with higher bertha armyworm moth counts are showing up in Alberta, Saskatchewan and Manitoba… -
The economic threshold is the density of larvae where the economic value of the yield lost due to feeding equals the cost of control… -
Insect trap counts are generally low across the Prairies, but bertha counts keep rising. Here are the latest provincial survey results…
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Growing degree days across most of the Prairies have reached the threshold for adult bertha armyworm (moth) emergence from overwintering pupae. That is 7-10 days ahead of normal. Egg laying begins shortly after adult emergence and young worms emerge about a week after that. Based on 2017 results, 2018 is not expected to be a bad year, but local flare-ups… -
A reader from southeast of Saskatoon emailed this question: I had a field with bertha armyworms on the perimeter in 2017. Numbers were not quite enough to reach spray thresholds, but very close. (I likely should have sprayed the perimeter.) My plans are to seed the field next to it to canola this year. Will this second field likely have… -
A heavily-infested field in western Manitoba (south of Riding Mountain National Park) generated a lot of interest on Twitter in the past week. It prompted a lot of scouting, which is good. But what this one field and the ensuing scouting demonstrated is that bertha armyworm population spikes can be highly localized…
