Integrated Pest Management of SWD

Prevention - This is only effective if the pest has not made it to the targeted area.  Use sanitation practices to destroy fruit culls.  Remove other potential SWD habitat.  Promptly remove all non-marketable hanging fruit from your fields.  An ounce of prevention is worth a pound of cure.

Forecast modeling - With knowledge of pest behavior, environmental modeling can be used to predict pest activity.  OSU's Integrated Plant Protection Center has develped a prelimary phenological model for SWD activity.  The model predicts possible insect developmental stages based on growing degree-day thresholds derived from historic and current research.

Monitoring - Set out monitoring traps once average air temperature meets or exceeds 50 F for several days.  Install one trap per five acres, with a minimum of three traps per farm.  Strategically place traps where you would likely recover flies - near adjacent earlier-fruiting plants, near field margins, and where crop residues are stored.  Check traps once per week for presence of SWD.  Males can be identified quickly by the characteristic large spots at the tips of the wings.  Females are more difficult to confirm and can be identified by the saw-like ovipositor viewed under magnification.  Check for fruit infestation by using the fruit dunk flotation method.  Larvae will float to the top and fruit pulp will sink when you pour sugar-water into a plastic bag partially filled with crushed infested fruit.

Habitat modification - Remove alternate hosts from areas surrounding your growing site.  Potential wildland hosts in Oregon include snowberry, evergreen blackberry, wild rose, flowering cherry, crab apple, and other fruiting species.  Hot, dry sites may be less suitable for SWD development. - Note - although wild species may potentially provide habitat for SWD, they may or may not be a preferred host.

Host resistance - Select thick-skinned fruit cultivars, which may inhibit oviposition by gravid females.

Biological control - Gall wasps (Hymenoptera: Cynipidae) emerged in 2009 from SWD-infested fruits collected in Oregon.  It is unknown how effective the wasps are for biological control.  Entomopathogenic fungi, bacteria, and additional parasitoids may prove valuable to keep SWD populations below threshold levels.

Bait sprays* - Certain compounds may have attractant properties.  These baits may be applied away from the crop plants and might attract pest insects, keeping them away from the crop.  NOTE: Baits have not yet proven effective at preventing SWD in the field.

General-use insecticides* - If you must apply pesticides, use the softest chemicals that will provide adequate control.  Use only registered compounds and apply according to the label.  Rotate insecticide classes to avoid resistance.

Restricted-use insecticides* - If you must apply pesticides, use the softest chemicals that will provide adequate control.  Use only registered compounds and apply according to the label.  Rotate insecticide classes to avoid resistance.

  •  Remember that when making chemical applications, the label is the law.  Always follow label instructions and wear proper personal protective equipment.  Be certain you can legally apply the compounds you choose.