We have had a mostly cool, and sometimes wet, March. These temperatures have set the weevil hatch back a few days from last year, but projected degree days indicate the hatch is just around the corner in southern Iowa. Proper management of this pest requires timely scouting, correct identification, determination of population levels, and if necessary, cutting the hay or spraying an insecticide. Alfalfa weevil larvae can be very destructive to first-cutting alfalfa, so fields should be scouted. Larvae remove leaf tissue, beginning with the new leaves at the top of the plant, then work down the stem to other leaves. This feeding reduces forage quality and quantity.
Rice, Marlin E. and Pope, Rich, "In spite of cool weather, weevils will hatch" (2006). Integrated Crop Management News. 2344.
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