New England Corn Growers Save Sprays By Watching Cycles Project uses parasitic wasps that move from field to field controlling European corn borer
The New England Vegetable and Berry Growers Association proposed to increase the adoption of a field scouting program in the use of biopesticides and reduced-risk pesticides among New England sweet corn growers. The crux of the program was to monitor for pest populations and cycles, spray only when necessary, and to use reduced risk materials when spraying was a must. The project was developed in conjunction with the Center for Agricultural Partnerships using the CAP Blueprint for IPM Implementation, “Working From The Ground Up,” (the result of a EPA/Pew Charitable Trusts/AFT/CAP collaboration between 1997-2002).
Project goals and objectives
The project had 2 objectives: 1. Implement and support a scouting program with 34 sweet corn growers in ME, MA, NH, CT; and 2. Coordinate use of reduced risk and biopesticides with the scouting program for participating growers.
All participating growers felt that on-farm scouting was the preferred method of deciding when to spray. This was preferred over relying on trap counts published in Extension newsletters, although that worked well in the past. About 60% of growers hired a scout and the remainder scouted their own fields. Growers also said that on-farm scouting resulted in fewer sprays needed, better overall control, less ear damage, they saved money and made more profit, and that they had fewer machinery repairs and maintenance due to less spraying. In general growers who scouted on-farm reduced the overall number of sprays per acre from 5 to either 3 or 4 on average. Earlier in the season, when pressure was lower, growers consistently saved 2 sprays per acre.
The greatest savings were on farms of direct participants (675 acres of sweet corn) in the four-state region. In the early part of the season, these growers saved 2 insecticide applications per acre ($18/acre X 675 acres = $12,150). The amount of pesticide use reduction was 506 pounds of the higher risk materials. This information was also passed to other growers (2818 acres) who saved 1 spray ($50,724). The additional amount of high-risk pesticide pounds reduced was 1057 pounds. Overall reduction in high-risk pesticides was 1563 pounds.
Another control used in the New England project was the trichogramma wasp, a very small insect that parasitizes European corn borer eggs. “When they were done in the first field they moved to two or three other fields and did a good job controlling the borer there,” he said. Trichogramma wasps were able to move by themselves to later plantings and provide control of this pest, saving sprays. Control with these wasps was excellent in the later plantings.
* A total of 34 growers participated (more than anticipated)
* 100 Acres were sprayed with indoxacarb, 80 with spinosad, and 34 were treated with trichogramma
* 675 new acres were scouted.
All scouting information generated on these 34 farms became part of the weekly pest messages published by the various state Extension services. This information reaches growers representing 80% of the sweet corn acreage. Overall, at least 20% of the acreage is treated based on the results published in these weekly messages.
The following sites contain current and archived newsletters and pest management messages.
Project is also featured on the Center for Agricultural Partnership website: www.agcenter.org/proggroundupprojne.html