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Moisture before and during and following flowering was the biggest factor driving up sclerotinia stem rot infection this year. Moisture as rain or high humidity or dew through the period from two weeks before flowering through early podding has increased the sclerotinia risk considerably, no matter the rotation history of the field. Most regions had these conditions this year. Fungicide…
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Some regions are reporting higher rates of blackleg (shown above) and most regions are seeing sclerotinia stem rot damage. Fungicide is not effective at this stage of the season, but the weeks leading up to harvest are a good time to scout. Its important to know which disease is present in order to plan rotations and varieties for next year…
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In fields badly infected with sclerotinia, swath when the healthiest plants are ready. These plants will provide most of the yield. Swathing early will not preserve seeds in badly infected plants — those seeds are unlikely to mature no matter when you swath…
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When crops are maturing rapidly in hot conditions, swathing before 50-60% seed color change on the main stem may not give chlorophyll time to clear from immature seed. Some fields may require additional moisture — rain — in order to re-hydrate the seed so chlorophyll can clear. If growers feel they must swath at less than 50-60% seed color change…
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Bertha armyworm larvae have started to feed in some locations, and the second generation of lygus has arrived in the southern Prairie. Watch pods and upper foliage for signs of feeding, and scout all fields. While scouting, also look for signs of blackleg, clubroot and foot rot (shown above). Late season foot rot has shown up in some fields, with…
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Second generation lygus have arrived. Young nymphs will reach late instar and adult stages in 5 to 14 days. When scouting to see if lygus numbers are near thresholds, include later instars — the ones with black dots on their back — as well as adults in the count. Bertha armyworm larvae are starting to feed in some locations…
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Some fields may have a variety of green worms feeding, including bertha armyworm, diamondback moth larvae, imported cabbageworm and alfalfa looper. Here's how to tell them apart…
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We don’t have scientific evidence to combine thresholds, but where an “additive” effect of multiple species can make sense is when more than one species are feeding on key yield-producing areas — flowers, buds or pods — at the same time…
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Lygus, bertha armyworm and diamondback moth have a number of natural enemies that will keep populations in check. These beneficial insects may not control an immediate insect threat — growers will still have to spray if economic thresholds are reached — but beneficials can keep a lid on populations. The key to preserving beneficial insects is to follow thresholds and…
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