How to Manage Pests
UC Pest Management Guidelines
(Reviewed 1/17, updated 1/17)
In this Guideline:
Alfalfa is an important reservoir for natural enemies of insect pests. These natural enemy populations often develop in alfalfa fields and expand into other plantings such as cotton, melons, and beans.
Several species of parasitoid (parasite) wasps are found in alfalfa
Several species of predaceous bugs are found in alfalfa. These predators feed on a variety of pests such as alfalfa weevil larvae, aphids, alfalfa caterpillars, beet armyworm, western yellowstriped armyworm, webworms, leafhoppers, and three-cornered alfalfa hopper.
Birds are important predators of insect and rodent pests in alfalfa. Egrets, ibis, and gulls feed on crickets, cutworms, and other insects that are forced to move at the leading edge of flood irrigation water. Blackbirds eat alfalfa weevil larvae, aphids, cutworms, and other insect pests.
Do not apply pesticides to alfalfa until the economic treatment level for a specific pest is reached and the predators and parasites have been assessed for their potential role in controlling the pest. Pesticides often harm natural enemies, leading to severe secondary pest outbreaks. See RELATIVE TOXICITIES OF INSECTICIDES AND MITICIDES to find out which pesticides are most compatible with natural enemies.
NATURAL ENEMIES AND THEIR COMMON PREY IN ALFALFA
UC IPM Pest Management Guidelines: Alfalfa
Insects and Mites
L. D. Godfrey, Entomology, UC Davis
Acknowledgment for contributions to Insects and Mites:D. R. Haviland, UC Cooperative Extension, Kern County
M. Rethwisch, UC Cooperative Extension, Riverside County (Blythe)
C. G. Summers, Entomology, Kearney Agricultural Research and Extension Center