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Spotted Wing Drosophila


spotted wingspotted wing pattern

Hosts:  all fruits

  Overwinter as adults and pupae, but it is unknown whether SWD can survive northern Utah winters.  Adults lay eggs inside fruit and maggots feed on pulp.

  Sunken fruit; holes in fruit.

  SWD has been found in northern Utah in very low numbers, and in north-central Idaho in high numbers.  Monitoring should be done using traps containing a cider vinegar or sugar-yeast bait.  See the USU Spotted Wing Drosophila factsheet for more detailed information on monitoring techniques.

Treatment Threshold:
  None determined yet.

Degree Day Model:

  • Lower threshold:  50F
  • Upper threshold:  88F
  • Start date:  Jan 1
  • Peak adult emergence:  755 DDs after Jan 1

Management Considerations:
  Monitoring will help to determine if this pest has been introduced to your area.