Commercial Growers

Counties may be quarantined in whole or in part based on trap catches and other evidence of apple maggot activity. The quarantine aims to slow the spread of apple maggot in Washington.

The purpose of the quarantine is to facilitate the movement of commercial fruit to domestic and international markets by providing shippers with one of two types of WSDA documents certifying their fruit is apple maggot free:

• A certificate stating no apple maggot flies were caught within half a mile of the orchard shipping the fruit.
• A certificate stating flies were caught within half a mile of the orchard but that WSDA inspection revealed no apple maggot larvae in the fruit.

To learn more about orchard certification, visit the WSDA Fruit and Vegetable Inspection website by clicking here. It is prohibited to ship commodities regulated for apple maggot outside of the quarantine area, into the pest-free area unless conditions outlined in WAC 16-470-115 are met. 

Quarantine areas are established as part of WSDA's apple maggot control program in collaboration with statewide stakeholders. The program consists of three components:

1. WSDA conducted apple maggot surveys and regulation
2. County pest board control, suppression, and eradication programs
3. Education through the Washington State University Extension Program

Information about managing your orchard for apple maggot can be found on Washington State University's Tree Fruit and Extension Center's website.

Trapping and Control
WSDA conducts an apple maggot trapping program. Between 5,000 and 8,500 traps are placed in the field each summer. These field activities are determined by the Apple Maggot Working Group. Trapping results are provided to county pest boards who use the information to plan control, suppression, and eradication activities as needed. 

Owing to the aggressive and collaborative nature of the program, apple maggot has never been found in commercially packed fruit in Washington.