When EPA revoked all tolerances for the insecticide chlorpyrifos in 2021, peanut growers in Georgia were left with no effective chemistry for managing peanut burrower bug and the rootworm complex.

Two peanut crops have now been grown since the loss of chlorpyrifos, and while injury due to burrower bug was low during that time, the same cannot be said for rootworm. Though there was little reason to believe growers would ever be able to use chlorpyrifos again on peanut, a ruling by the U.S. 8th Circuit Court of Appeals in November of 2023 vacated the EPA’s 2021 decision and resulted in the reinstatement of tolerances for the insecticide.

What does this mean for peanut farmers? It means that chlorpyrifos can legally be used on peanut in 2024, but there are some important things to consider.

First, just because there is a tolerance for an active ingredient does not mean that it can be used. There must be a legally registered product, and registration is different than tolerance. Any product containing chlorpyrifos that had its registration cancelled is illegal to use. Any product for which a registration is still in place would be legal to use.

Second, the granular formulation is the only one that can legally be applied to peanut after planting; there are no liquid chlorpyrifos products labeled for foliar use in peanut.

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Third, state laws should be reviewed as they can be more restrictive than federal law. In the case of Georgia, a granular chlorpyrifos product that is currently registered for use on peanut can be used in 2024.

Fourth, and very importantly, some peanut contracts preclude a grower from applying specific active ingredients; it is up to the grower to carefully review his or her contract. 

Finally, EPA has stated that it will move “expeditiously” to re-revoke tolerances for all but 11 crops. Peanut is not one of the 11. Growers should not expect to be able to use chlorpyrifos on peanut in 2025.

Growers should consult their local county Extension agent if they have questions regarding chlorpyrifos use on peanut in 2024.

Abney is the UGA Extension peanut entomologist.