Bt corn traits that are potentially available in Tennessee are quite numerous, and non-Bt corn refuge requirements vary depending whether you are in a corn only area or in a cotton growing area. Cotton growing areas in Tennessee include the counties of Carroll, Chester, Crockett, Dyer, Fayette, Franklin, Gibson, Hardeman, Hardin, Haywood, Lake, Lauderdale, Lincoln, Madison, Obion, Rutherford, Shelby, and Tipton.  A larger refuge of non-Bt corn is often required in cotton growing areas.

The table below rates the performance of various Bt corn traits against common pests.  It also rates performance of technologies that have Bt traits for western corn rootworm.  Keep in mind that western corn rootworm is a rare problem in Tennessee.  However, refuge guidelines are affected by whether a hybrid also contains Bt traits for the control of western corn rootworm.  Pay attention to the asterisks and associated footnotes at the bottom of the table.  These describe refuge requirements.  You should double check company licensing requirements to make sure you are in compliance.

You will also see refuge-in-a-bag (RIB) options for corn growing areas only.  This is where the non-Bt refuge seed is mixed in the bag with Bt corn, either at a 5% or 10% level, depending upon the trait package selected.  Note that some of the options below, although technically available, may be of limited supply or not marketed heavily in Tennessee.

Bt Corn and Refuge Options

* 50% and 20% non-Bt corn refuge requirement in cotton and corn areas, respectively.

** 20% non-Bt corn is required in cotton and corn areas.

*** 20% and 5% refuge requirement in cotton and corn areas, respectively.

**** 5% refuge in bag system in non-cotton areas (20% refuge is required in cotton growing areas).

***** 10% refuge in bag system in non-cotton areas (20% refuge is required in cotton growing areas).