That 20% non-Bt refuge applies whether you are planting YieldGard, Herculex or Agrisure, according to Ohio State University agronomists. However, the rules vary for refuge placement depending on the insect.
For corn borers, the refuge can be inside, adjacent to or within one-half mile of the Bt.
For rootworm, the refuge has to be in the same field or adjacent to the Bt field.
For stacked hybrids, Ohio State recommends a common refuge in or next to the Bt.
Your planting options for the non-Bt refuge are numerous. Adjacent fields can be separated by a ditch or a road. Internal refuges can be a block, a strip alongside the field, or split rows with your corn planter. The stewardship of biotechnology is a priority for researchers and NCGA. For more information, check www.ncga.com/biotechnology/insectMgmtPlan/index.htm.