Apple Maggot Control in the Backyard Orchard

Organic Control:

Baited Sticky Traps
• Bright yellow panels or red balls are coated with a mix of brush-on Tangle-Trap and ammonium acetate (available at some pharmacies and laboratory chemical suppliers). Some experimenters have used ammonium carbonate instead but tests indicate that addition of ammonium carbonate lures do not enhance captures of mature flies and its slight enhancement of trap captures of immature flies may not be great enough to justify its use.

• Make panel traps from 1/4" to 1/2" thick wood and cut to 5 1/2" x 9". Paint with a coat of exterior white primer followed by a coat of lemon yellow fluorescent paint. Slip the panel into a clear plastic envelope and install a staple or screw eye on a long edge and put another on a short edge.

• For balls use wood croquet balls or commercially available red plastic balls. Paint wood balls dark red. Add a hook for hanging.

• Mix your bait: l/4 teaspoon ammonium acetate crystals and 3 tablespoons "brush-on" formula Tangle-Trap. Mix well.

• Coat all surfaces of plastic cover on the panel. Hang trap by wire on south side of tree canopy up among the apples. Wire end of trap to some portion of tree to keep trap from swinging.

• Clear leaves from around trap to prevent contact with the sticky coating.

• Coat balls directly with mix and hang in similar location in tree.

• Deploy traps by early-July. Sticky bait must be renewed every 2 weeks. Replace plastic envelope on panel traps and apply new bait. Scrape balls to clean them and recoat with bait.

Clean Up
• Remove all fallen fruit daily until harvest. Boil fruit to kill any larvae inside before burying or composting it, or keep in lock tight bags and dispose with garbage.

Pesticide Control:

• If you wish to control by spraying, make first application within 7 days of catching first apple maggot fly in a trap. Refer to WSU Extension Bulletins EB1928 , Protecting Backyard Apple Trees from Apple Maggots (PDF file). Growers on the east coast have used a threshold of 5 or more flies caught on a trap to time repeat sprays.

University of California WSU Extension Apple Maggot FAQ

Effects of Natural Food Sources on Attraction of Apple Maggot Flies to Baited Traps Fruit Notes Juan Rull, Alan Reynolds, Michelle Bakis, Holly Gagne, and Ronald Prokopy Department of Entomology, University of Massachusetts

Written by Oren Vallen, Washington Cascade Fruit Society
Reviewed 8-98 by Art Antonelli, Entomologist WSU Puyallup
Slightly revised 07-02 by Dave Pehling, Snohomish Co. Extension Analyst

For more information contact your local WSU Extension Office.