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Bertha armyworm got its name because the worms will march like an army in search of food. As canola crops dry down and are swathed, bertha armyworms that have not pupated will keep moving in search of lush green plant material. Late canola fields could be in the crosshairs of this army…
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Bertha armyworms keep eating to within a few days of pupating. These 1.5” late-stage berthas eat much more than at smaller stages, doing a lot of damage in a week if numbers are at thresholds…
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Bertha armyworm spraying has been reported in a few fields. Scout lower in the canopy this week, looking for larvae feeding on lower leaves. Scouting now will give you a couple weeks’ planning time before leaf drop begins and berthas start moving up toward the pods — where they do their most costly damage. By holding off until bertha larvae…
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Bertha armyworm spraying has been reported in a few fields. Scout lower in the canopy this week, looking for feeding on lower leaves. Spotting them down low will give you……
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Thrips damage shows up in some fields. Bertha armyworms are the bigger issue, with adult counts continuing to build and many areas now at moderate risk, or higher. Read more to see links to latest maps and counts…
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Bertha armyworm moth counts continue to accumulate across the Prairies. Many areas are now at moderate to high risk, and adult numbers will continue to build this week. Adult counts can hint at the potential level of feeding by the larvae — the actual armyworms — starting about two weeks after the first wave of adults showed up in traps…
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—Go out in early morning or late evening when larvae are mostly active. —Mark out an area a quarter-metre square (50 cm by 50 cm) and beat the plants growing within that area to dislodge the larvae. Count the larvae that have fallen to the ground and multiply by 4 to get the number per metre square. Larvae will hide…
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Bertha armyworm adult trap counts suggest low to medium risk in most areas this year, with a couple higher risk hot spots in Saskatchewan — south of Regina being the largest. (See the map above.) Any need to spray is at least two weeks away. Larvae do the damage, and spraying should only occur if larvae feeding reaches threshold levels…
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In parts of central Alberta, lygus counts continue to exceed thresholds significantly (with counts as high as 450 lygus in 10 sweeps in some fields). In other areas, lygus numbers are just at or approaching threshold but the crop is very near to swathing. With these counts, growers are encouraged to resist the urge to simply spray and to be…
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