2016 Corn Rootworm Hatch Update

After a generally warm late winter and early spring across much of the corn-growing region, April and early May temperatures have shown a tendency to be on the cooler side of average with brief periods of above average temperatures and periodic rainfall events. As a result, four inch soil temperature accumulations (which are a good indicator of initial corn rootworm hatch) have been running behind last year’s pace at many locations at this point in the growing season. In general, most sites especially across the southern reaches of the corn-growing region where corn rootworm hatch usually commences, are about five to ten days behind last year’s accumulations, with portions of northeast Kansas running slightly ahead of last year at this time (as of May 12). The first corn rootworm hatches this year are predicted to be in fields in northeastern Kansas during the May 20-25 time period. Further corn rootworm hatches are predicted to occur closer to Memorial Day and into early June at additional fields mainly south of I-80 where corn rootworms are present.