Across the corn belt depending on time of year | Refuge strips were actually the best. Emerging beetles from both sections (Bt and non-Bt) were in close proximity and had a greater chance of inter-mating, thus diluting any genes for resistance.
I actually have some wonderful pictures from fields in Mn where the refuge strips treated with insecticide are standing and the Bt-RW rows are lodged. First real sign of rootworm resistance. These were aerial shots and about 2010 if I remember correctly. Taken by Ken Ostlie, Univ Mn. |
rootworm damage on CRW corn paid for by seed companies
