Sweet Corn Pheromone Trap Network

for Western NY - 2008

This is a seasonal scouting report giving growers in the Western New York area information on the presence of sweet corn pests and recommendations on scouting and thresholds. The report is written by Abby Seaman, NYS IPM's Area Extension Educator for Vegetables.

For 9/16/08

Both E and Z race European corn borer catches continue to be in the single digits at all locations this week.  Corn earworm are being caught at all trapping locations, with catches as high as 68 at two locations.  With fewer and fewer fields in the green silk stage, earworm pressure is likely to increase in the few remaining fields, and fields with drier silk my experience more pressure than they would if green silk fields were available.  With the cooler temperatures in the forecast, remember to add a day to the recommended spray intervals in the table below.  Fields within a week of harvest do not need additional sprays.  Newly hatched larvae will be very small and not noticeable to the consumer.  Fall armyworm catches jumped to the teens at a few locations this week.

Once CEW are being caught in higher numbers, insecticide applications in silk stage fields should be determined by CEW trap catches.  The recommended spray intervals for CEW should be adequate for ECB and FAW control.  Because CEW lay their eggs directly on the silk, and eggs are difficult to find in the field unless the population is VERY high, we rely on pheromone trap catches rather than scouting to make CEW management decisions.  It is most important to adhere to the recommended spray intervals when the field is in the green silk stage.  The chart below indicates recommended spray intervals during the silk stage for a range of trap catches:

Average CEW Pheromone Trap Catches

Add one day to the recommended spray interval if daily maximum temperatures are less than 80° F for the previous 2-3 days.

These pages are maintained by the New York State IPM Program, part of Cornell Cooperative Extension. All material is protected by Section 107 of the 1976 copyright law. Copyright is held by Cornell University and the New York State IPM Program.

Webmaster | Site Map