Manitoba Agriculture, Food and Rural Initiatives has issued its weekly insect and disease update. Full text and photos are alongside.
• Lygus bug numbers have been above the economic threshold in some canola fields in the central and eastern regions of Manitoba.
• Bertha armyworm have been hatching and are starting to be noticed in some fields, although currently not at economical levels.
• Blackleg — a reminder for agronomists and growers to be scouting for blackleg in canola fields as they begin to mature. There have been cases of basal stem lesions in canola fields this year in which plants are falling over due to this girdling of the stem base.
• Green cloverworms — larvae are now starting to turn to pupae. So you may see holes in the upper leaves of some soybean plants and not find caterpillars present.
• Armyworms are now starting to turn to pupae in some regions as well. They have been at economic levels in cereal crops and forage grasses in many parts of Manitoba this summer.