Survey Finds High Level of IRM Adherence

EPA survey reports more than 90% of growers adhering to Bt stewardship requirements. Compiled by staff

Published on: Jan 6, 2005

For the fifth year in a row, a large majority of corn growers are adhering to insect resistance management (IRM) requirements designed for corn borer resistant Bt corn, according to an annual survey required by the U.S. Environmental Protection Agency (EPA).

More than 550 Bt corn growers in the Corn Belt and Cotton Belt were interviewed for the survey during the 2004 growing season. The results from the survey, which was conducted by an independent research firm for the Agricultural Biotechnology Stewardship Technical Committee (ABSTC), highlight that more than 9 out of 10 growers, or 91%, met regulatory requirements for IRM refuge size, while 96% met refuge distance requirements.

According NCGA President Leon Corzine, these results validate corn growers’ commitment to being good stewards of Bt technology as well as the effectiveness of a comprehensive, ongoing IRM awareness effort spearheaded by NCGA, the Bt corn registrants and other key stakeholders.

"Awareness is key to informed decision-making about why and how to comply with IRM refuge requirements," says Corzine. "Product stewardship is everyone’s responsibility. As growers, we understand the economic and environmental benefits that Bt technology provides and want to do what we can to make sure Bt corn remains effective against pests and is a tool that is readily available for all of us."

Survey results indicate that seed company and one-on-one dealer interaction has been a critical factor in getting the word out to farmers. Ninety-six percent of survey participants ranked seed dealers and their seed companies as "important" sources of information — with 85% of growers recalling they had an individual conversation with a seed company representative.

Not only did the majority of survey respondents indicate they were aware of IRM requirements, but 96% of Bt corn growers says they received enough information to properly implement a refuge in 2004, which is seven percentage points higher than 2002 and 22 percentage points higher than 2001 survey results.

The IRM requirements established by the EPA, the Bt corn registrants and academics in 1999 obligate growers to plant at least a 20% refuge — that is, corn that does not contain a Bt gene for controlling corn borers — and ensure every Bt cornfield is located within one-half mile of a refuge. In certain corn/cotton areas of the South, growers are required to plant at least a 50% corn refuge. These IRM refuge requirements were enacted to help minimize the probability of corn insect pests, such as the European corn borer, from developing resistance to Bt technology, enabling the technology to be used well into the future.