Pests of Alfalfa Grown for Seed

Doug Walsh
Revised: 
March 2021

In all cases, follow the instructions on the pesticide label. The PNW Insect Management Handbook has no legal status, whereas the pesticide label is a legal document. Read the product label before making any pesticide applications.

Note: Products are listed in alphabetical order and not in order of preference or superiority of pest control.

Important notice Several pesticides registered for use on alfalfa seed lack legal tolerances established for residues that may be on the seed, screenings, or hay. Therefore, certain alfalfa seed grower associations in Washington, Oregon, Idaho, Wyoming Montana, and Nevada have declared, through their respective state departments of agriculture, that alfalfa produced for seed in those states is a nonfood-nonfeed crop. This declaration means that none of the seed, screenings, or hay will be available for human or animal consumption when special nonfood pesticides registered via 24C Special Local Need have been applied.

EPA and Washington Department of Agriculture have classified most, but not all, small-seeded vegetable seed crops grown in Washington as nonfood/nonfeed crops for pesticide registration purposes.

Alfalfa seed producers should verify the legality of using the products in this section with both a current label indicating that a product is registered for use on alfalfa grown for seed, and the appropriate state department of agriculture.

IMPORTANT NOTICE REGARDING THE USE OF CHLORPYRIFOS:

The State of Oregon has adopted new restrictive rules on the use of chlorpyrifos-containing products in Oregon. Please refer to Oregon Department of Agriculture
Permanent Chlorpyrifos Rule at

https://www.oregon.gov/oda/programs/Pesticides/RegulatoryIssues/Documents/Documents/2020/ChlorpyrifosRule.pdf