Chesapeake Bay Project
From The Ground Up
England Vegetable and Berry Growers Association]
New England Corn Growers Save Sprays By Watching
Project uses parasitic wasps that move
controlling European corn borer
New England Vegetable and Berry Growers Association intended 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 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.
Ph.D., past president of the association and coordinator of the
project, worked with extension specialists and agents in four states
who help growers combat the European corn borer and fall armyworm.
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 good news
for corn producers is their growing cycles did not always coincide
with pest emergence cycles, and field scouting helped to reveal
such cycles. “Continuing from early July to about mid-October,
you might harvest 15 different plantings,” said Bonanno. “You
seed the corn every few days from mid April through June,”
he said. “If you do a good job of monitoring, you may find
that you have certain plantings that don’t coincide with the
emergence cycles of insects. By knowing what the population is doing,
you may not have to spray and if you need to spray, you can try
to pick softer products.”
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.
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
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
- 675 new
acres were scouted.
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.
Use of biopesticides
(trichogramma) and reduced-risk pesticides (spinosad, indoxacarb)
is considered to be safer for the applicator. In some cases, the
efficacy of the reduced-risk product may be better than the standard.
In addition, scouting data generated on farm will provide growers
with the best data with which to make a decision to spray. Adoption
of these technologies will increase applicator and environmental
safety, improve efficacy at times, and increase yield and profitability.
This type of
work will continue within New England. Research and Extension work
in sweet corn has been ongoing since the 1970’s. New pesticide
products including reduced-risk pesticides, biopesticides, scouting
techniques, and pest changes provide a continuous opportunity and
need to improve these practices. Dollars likely to be expended on
these efforts in 2006 will include Federal and State dollars, private
donations, US EPA Strategic Ag Initiative dollars, and Industry
support dollars. Specific efforts will involve, increasing the numbers
of growers who scout themselves, advocating for the increased use
of biopesticides, research work on the timing, mobility, and overwintering
capacity of trichogramma, and efforts to improve the email distribution
of pest trapping data.
sites contain current and archived newsletters and pest management
was partially funded through EPA Assistance Agreement R 82856801-05
with American Farmland Trust.