Beginning last week, I have seen and heard about an aphid explosion - in corn! For the last three to four years, certain areas in Iowa have had serious problems with aphids infesting corn in August. The areas having problems right now include the northeast and northwest corners of Iowa and west central Iowa. Some of these heavily-infested fields were sprayed with an insecticide earlier this year. From my observations this week, I noticed aggregated colonies at the end rows.
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