IPM Field Crops: Who Cares and Why?

In recent years, reduced crop prices, drought conditions, deer damage and migratory insect
outbreaks have resulted in economic losses for field corn and soybean producers. Delaware
producers and private consultants have expressed an interest in new insect management
technology, deer management strategies and regional information on pest occurrence to help
reduce input costs and reduce risk from pest infestations.

What Has Been Done:
In 2002, regional field crop IPM efforts continued in the areas of multi-state pest management
recommendations, IPM workshops, CCA training workshops and regional CCA IPM exam. New
innovations in field crop insect management focused on the use of new treatment thresholds and
management options for aphids, the evaluation of new seed treatment technology to reduce soil
insecticide use in field corn, the early detection of a migratory insect pest, the beet armyworm
(BAW) and a new insect pest, the soybean aphid. Since BAW did reach outbreak status in
soybeans in Sussex County and this insect is resistant to currently labeled insecticides, a
combination of efforts by the Department of Agriculture and Delaware Cooperative Extension
resulted in a Delaware label for a new insecticide, Steward, within 2 days of the detection of
economic levels. New management strategies were introduced to producers and consultants at inseason
field meetings, over the IPM web site, on biweekly recorded messages, through county
based pest alerts and as part of the Weekly Crop Update newsletter.
Results from on-farm research on seed treatment technology indicates that growers could save
$12 per acre in reduced soil insecticide use for wireworms in field corn. Soybean aphid was
detected in Delaware for the first time in 2002 as a result of a weekly statewide survey funded by
the Delaware Soybean Board. Although this pest can cause up to 15% yield loss, the pest
incidence was low and no economic losses occurred in Delaware. As a result of multi-state
surveys for this pest, entomologists in the Mid-Atlantic region (Maryland, Delaware and
Virginia) now agree that in most years, soybean aphid populations will arrive late in the season
and therefore have little, if any, impact on yield. A combination of in-state and regional
monitoring and communication efforts prevented a 20% yield loss on 30% (30,000 acres) of the
soybean acres in Sussex County.
Primary Impact Areas: Extension
Funding Sources: Federal Smith Lever 3-D IPM Funds, State IPM Funds, Delaware Soybean
Board Grants, Industry grants

Contact Information:
Joanne Whalen
Extension IPM Specialist
Department of Entomology
University of Delaware