The Honey Bee Precaution Pesticide Ratings may differ from the pollinator precautionary statements on pesticide labels. These ratings come from the UC IPM Bee Precaution Pesticide Ratings and are developed independently from the Pest Management Guidelines. They are meant to provide supplementary information to help readers choose pesticides less hazardous to honey bee. For information about how these ratings are established, see Bee Precaution Pesticide Ratings Frequently Asked Questions. Users of pesticides must always comply with all label instructions and legal requirements, which represent the minimum precautions to protect honey bee.

• * ^{a b c}  Permit required from county agricultural commissioner for purchase or use.
• # ^{a b c d}  Acceptable for use on certified organic crops. Check with your certifier to confirm before application.
• ¹ ↩ Group numbers for insecticides and miticides are assigned by the Insecticide Resistance Action Committee (IRAC). Insecticides with unknown modes of action are assigned mode-of-action group numbers (MoAs) that begin with UN. Rotate pesticides with a different mode-of-action group number, and do not use products with the same mode-of-action group number more than twice per season to help prevent the development of resistance. For example, the organophosphates have a group number of 1B; insecticides with a 1B group number should be alternated with insecticides that have a group number other than 1B.
• ² ↩ Range of insect and mite groups affected by a pesticide. Broad means the pesticide affects most groups of insects and mites; narrow means the pesticide affects only a few specific groups.
• ³ ↩ Risk of harm to honey bees. For more information, see Bee Precaution Pesticide Ratings.
• ⁴ ↩ Risk of harm to predatory mites. Toxicities are generally to western predatory mite, Galendromus occidentalis. Where differences have been measured in toxicity of the pesticide-resistant strain versus the native strain, these are listed as pesticide-resistant strain or native strain.
• ^{5 a b} Risk of harm to parasitoids and general predators. Toxicities are averages of reported effects and should be used only as a general guide. Actual toxicity of a specific insecticide depends on factors including the application rate, environmental conditions, and the life stage and species of a parasitoid or predator.
• ⁶ ↩ Length of time residue affects natural enemies. Short means hours to days; moderate means days to 2 weeks; and long means many weeks or months.
• ⁷ ↩ Date information was last updated in the UC IPM Pest Management Guidelines.
• ⁸ ↩ Use lowest rates for best management of predatory mite to spider mite ratio.
• ^{9 a b c} Toxic to some natural enemies (lacewing and syrphid fly larvae, predatory beetles, and thrips) when sprayed and up to 5 to 7 days after.
• ¹⁰ ↩ Residual is moderate if solution is between a pH of 7 and 8.

UC IPM Pest Management Guidelines: Corn
UC ANR Publication 3443

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