Weeds aren't slowing down: Crop Pest Update

Summary

Insects: Economic populations of pea aphids on field peas have been reported from the Southwest and Central regions, and some insecticide applications have occurred. Grasshopper levels continue to be a concern in some areas.

Diseases: There is now a LOT going on in the disease world: bacterial blights in oats and peas, blackleg on lowermost leaves of canola, Septoria brown spot on unifoliate leaves of soybean, as well as higher risk of Fusarium head blight in small grain cereals and potential risk of Sclerotinia in canola.

Weeds: Warm weather over the past week has advanced crops rapidly, and unfortunately the weeds aren’t slowing down. The majority of herbicide spraying is done, with a few last applications to late seeded canola or a second spray in corn or soybeans. Warm season weeds like green and yellow foxtail and redroot pigweed are taking off and there are some reports of poor control of these. Warm temperatures and frequent rain have made ideal growing conditions for all C4 plants, both crops and weeds. Late flushes after herbicides were applied would not be controlled, and if weeds were bigger and toward the end of optimum staging then control could be less than optimum.