Corn Earworm
The weather pattern is predicted to remain active right into next week across much of the corn-growing region. High pressure is expected to remain rather persistent in the southeast United States while low pressure systems and associated cold fronts continue to develop east of the Rocky Mountains and move northeast through the Plains and into the upper Midwest. In between these two pressure systems, it is likely that south to southwest winds will continue through much of the next five days over at least portions of the corn-growing region. As a result, increased corn earworm migration risks are in place especially with the presence of active and higher moth count activity in source regions in the mid-south right now, including some of the highest moth captures in the middle Mississippi River valley so far this growing season. Growers with crops at susceptible stages to damage are encouraged to monitor traps and their fields for signs of new moths in the coming week. Moderate risks are confined to the southwest portion of the corn-growing region tonight into tomorrow morning, mainly across Nebraska, southwest Iowa, western Missouri, and Kansas as a weak area of high pressure in the upper Midwest and also in the eastern Midwest keeps any southerly winds further south and west. The Moderate risk, however, does expand north and east tomorrow night into Friday morning and includes Kansas, southeast Nebraska, Iowa, southeast Minnesota, central and southern Wisconsin, central and northern Missouri, central and northern Illinois, northwest Indiana, and southwest lower Michigan. By the extended portion of the forecast, a High migration risk enters the forecast on Saturday night into Sunday across the southern Great Lakes region as this area is predicted to fully tap the mid-south source region with persistent south to southwest winds for at least a couple of night and a cold front coming in from the west. Additional Moderate risks extend further west and east from the High risk area as yet another cold front is predicted to develop in the Plains and move east into the corn-growing region next week. The second cold front is predicted to pose Moderate migration risks from eastern Kansas northeast into Minnesota and Wisconsin by late in the weekend. For many fields, the primary corn earworm flight that continues to be predicted may miss critical growth stages especially for field corn except in areas that were late or re-planted but the fresh market and processing crops are especially at risk in the next week.