Pure-Gro

Taylor AG Industries, Salt River Valley Farms, and 5J Farms (collectively “Appellants”) appeal the district court’s grant of summary judgment on their state law tort and contract claims. The district court granted summary judgment on the ground that the preemption provision of the Federal Insecticide, Fungicide, and Rodenticide Act (“FIFRA”), 7 U.S.C. § 136v(b), preempts all of Appellants’ claims. We affirm.

*558 I

Appellants are partnerships engaged in cotton farming in Arizona and sued to recover for damage to their cotton crop. The damage allegedly resulted from the application of a mixture of two defoliant chemicals, DROPP 50WP (“DROPP”), manufactured by Nor Am Chemical Company (“Nor Am”), and DEF-6, manufactured by Miles Inc. (“Miles”), formerly Mobay Corporation.

The labels on the two defoliants and the 1991 DROPP Product Guide (“Product Guide”) recommended a mixture of the two chemicals to improve defoliation in the conditions present in Arizona. However, there was a discrepancy in the dosage rates indicated in the DROPP label and the DEF-6 label: The DROPP label and the Product Guide recommended a maximum amount of DROPP to be applied with DEF-6 that was four times…