According to results of an annual survey required by the U.S. Environmental Protection Agency (EPA), 92 percent of farmers met regulatory requirements for IRM refuge size, while 93 percent met refuge distance requirements — an increase from 87 and 82 percent reported respectively in 2000 when the survey began. These results demonstrate the vast majority of farmers growing Bt corn borer resistant corn are adhering to IRM requirements.
EPA requirements established in 1999 obligate growers to plant at least a 20 percent refuge — or corn that does not contain a Bt gene for controlling corn borers — and that every Bt cornfield must be 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 percent corn refuge. These IRM refuge requirements were enacted to help prevent corn insect pests, such as the European corn borer, from developing resistance to Bt technology.
More than 550 growers responded to the survey conducted during the 2003 growing season among Bt corn users in the Corn Belt and Cotton Belt. The survey was conducted by an independent research firm for the Agricultural Biotechnology Stewardship Technical Committee (ABSTC) in conjunction with the National Corn Growers Association (NCGA).
The latest survey results validate the effectiveness of a broad-based, ongoing awareness effort, , notes Ken McCauley, a corn grower from White Cloud, Kan., NCGA Corn Board member and liaison to the NCGA Biotech Working Group
“Bt corn borer resistant hybrids provide growers with many economic and environmental benefits as well as improved grain quality in many cases,” said McCauley. “Following IRM requirements is very important — we’ve done a good job of complying so far and want to continue along this track to help make sure Bt corn remains effective against pests and a tool that is readily available for all of us.”
The recent Compliance Assurance Program (CAP) is another factor that has contributed to increased awareness of IRM in the grower community. Introduced by the seed industry in response to EPA requirements in 2002, the CAP was developed to further inform growers about the IRM requirements and how to implement them on their farms.
Under the CAP, registrants of Bt corn borer resistant corn must conduct on-farm visits with growers to check for IRM refuge compliance. Growers who do not meet their IRM refuge requirements in two consecutive years can be denied access to Bt corn borer resistant corn in the third year.
“Our experience has been that, as the number of information resources available to growers increases, so does compliance with the requirements,” said Dick Crowder, CEO and president, American Seed Trade Association. “We’re clearly seeing the fruits of this comprehensive education effort and will continue to work hard to meet our industry’s stewardship responsibility around this technology. Being good stewards benefits our customers, industry and agriculture.
The seed industry understands the importance of maintaining diligence in minimizing insect resistance and is committed to helping growers meet the IRM requirements,” he continued.
Survey results also report that seed company and one-on-one dealer interaction has been a critical factor in getting the word out to farmers. Ninety-four percent of survey participants ranked seed dealers and their seed companies as “important” sources of information — more than three out of four growers (78%) recalled having an individual conversation with a seed company representative. The survey also confirms that growers are receiving on average four pieces of IRM information each year, in addition to the onsite visits.
Not only did the majority of survey respondents indicate they were aware of IRM requirements, but 94 percent of Bt corn growers said they received enough information to properly implement a refuge in 2003, which is 5 percentage points higher than 2002 and 20 percentage points higher than 2001 survey results.
What’s more, the survey indicates that 72 percent of growers who used insecticides regularly before the introduction of Bt corn borer resistant corn (four or five of the previous five years) report decreasing their insecticide use to control corn borers.
Looking ahead to the 2004 growing season, McCauley and Crowder both suggest growers consult with their seed dealers and seed company representatives to help ensure they understand IRM requirements now. Growers also can visit the Know Before You Grow section of www.ncga.com  for more information on Bt corn and the IRM requirements.