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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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Root maggots and root disease often show up together in the same field. Root maggots are white and up to 10 mm (half an inch) long — just like maggots. Maggot feeding can damage root crowns and impede water movement, causing wilting. Severe feeding can cause plant death. Severe root maggot damage can occur in fields with back to back…
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The most accurate method to estimate diamondback moth population density in canola is to count larvae in several locations throughout the field, and determine the average population per unit area…
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As canola starts to move from flowering and into pod formation, growers will often notice blanks up the raceme where pods did not form. Here are 7 possible reasons…
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Cabbage seedpod weevil numbers are high in some regions of southern Alberta and southwestern Saskatchewan. The map shows CSPW reach for 2012. Growers and agronomists are encouraged to scout canola fields, and follow these management decision-making guidelines:…
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Many canola fields have a combination of insects feeding on the crop. An “additive” effect is possible when more than one species are feeding on key yield-producing areas — flowers, buds or pods — at the same time. For example, lygus and cabbage seedpod weevil have been found in the same fields in the southern Prairies this week. Preliminary results…