Extension Area Crop Pest Report

Growers have been finding high levels of alfalfa weevil and aphids. Fields have been sprayed but please refer to the pre-harvest intervals for insecticide applications. As far as aphids, different aphids have different economic thresholds. Use alfalfa weevil levels as a priority to guide spraying decisions.
The use of cover crops has provided additional complexity to herbicide program especially when managing glyphosate resistant weeds. The recrop intervals as provided on the herbicide label will some information of potential injury to planting a fall cover crop.
Weeds have an early start this spring with warm temperatures. Early herbicide applications may not last as long as you would typically expect. The early herbicide application timing should be monitored carefully for potential escapes as the weather impacts planting date.
Corn planting depth that is most concerning is too shallow especially in no-till. Coulters must cut residue and not hairpin residue into the seed furrow. Deep running of trash whippers may cause heavy rains to cut through the track especially if not running with soil slopes.
Watch fields coming out of CRP for additional pests or especially any fields that have not had typical management in the past. Pests such as white grub can be found especially the second year after coming out of sod. Scout fields carefully for crop injury.
Black cutworm moth flights in northwest Missouri have been light. As of this date, one may find an occasional area within a field that may have damage.
For more information, contact Wayne Flanary at 660-446-3724 or Heather Benedict at 660-425-6434, Regional agronomists, University of Missouri Extension.