2026 Insect Management for Wild Blueberry

Prepared by Philip Fanning, Assistant Professor of Agricultural Entomology.
Published February 2026.

Download This Chart

2026 Insect Management for Wild Blueberry Chart (PDF for printing)

This revised version replaces all previous charts.

Questions about Insect Management?

Contact Philip Fanning, Assistant Professor of Agricultural Entomology, at philip.fanning@maine.edu.

Cultural Insect Management

Are you sure you need to act? It is critical that we make sure an insect pest is present at damaging levels in a field before taking management action. Managing an insect is expensive in labor, equipment, and products, so make sure you have a problem before taking action. Scouting and adopting action thresholds to inform management decisions is key to reducing unnecessary or untimely applications of pesticides.

Cultural Management Methods by Pest

Harvesting: Harvesting techniques that reduce fruit loss can minimize the number of infested fruits left on the plants and on the ground.

Management: Keep isolated fields in the same cycle.

Winnower Cleanup: Compost, burn or dispose of winnower refuse.

Fire Pruning: Blueberry litter must be ignited.

Fire Pruning: Burn curled stems as soon as extensive curling occurs in early spring, but not later than July 1 in a nonbearing crop or reduction in next year’s fruit buds will occur.

Early Harvest: Monitor adult and larval populations.

Chemical Insect Management

Important: This guide is not a substitute for reading and following pesticide labels. It is unlawful to use any pesticide inconsistently with its label. The user assumes all responsibility for misuse. Trade names are used for identification only. No endorsement is implied. Check with your processor regarding PHI restrictions or MRL restrictions for export sales.

Group 1A

Target Pest(s):

  • Blueberry Maggot
  • Spotted Wing Drosophila

Spotted Winged Drosophila Control: Moderately Effective
Active Ingredient(s): Carbaryl
Signal Word: Warning

Rate:

  • See label (varies by formulation)
  • Maximum: 5 applications, 10 qt per acre per crop year

PHI: 7 days
REI: 12 hours
Aerial/Drone Application: Depends on formulation.

Important Notes:

  • Do not apply more than once every 7 days.
  • Do not apply during bloom or just prior to bloom.
  • Avoid irrigation for 48 hours post-application.
  • Flea beetle adults only.
  • Not systemic (NS).
  • 7-day environmental persistence.

Human & Environmental Risk:

  • Moderately toxic to fish.
  • Extremely toxic to bees.

Group 1B

Target Pest(s): Thrips
Active Ingredient(s): Diazinon
Signal Word: Caution

Rate:

  • See label (varies by formulation)
  • Maximum: See label (2 lb ai)

PHI: 7 days
REI: 12 days
Aerial/Drone Application: Not permitted.

Important Notes:

  • Do not mix with any Captan product.
  • See label for dilute vs. concentrated spray.
  • Make first application when sprouts are 0.25–0.5 inch.
  • Make second application when sprouts are 0.5–1 inch.
  • Avoid applying when bees are present.
  • Not systemic (NS).
  • 11-day environmental persistence.

Human & Environmental Risk:

  • Moderately toxic to people.
  • Extremely toxic to fish.
  • Extremely toxic to birds.
  • Extremely toxic to bees.
  • Toxic to shrimp and crabs.

Target Pest(s):

  • Spotted winged drosophila
  • Thrips

Spotted winged drosophila, Thrips
Spotted Winged Drosophila Control: Effective
Active Ingredient(s): Malathion
Signal Word: Warning

Rate:

  • See label
  • Maximum: 1.25 lb ai per acre
  • 3 applications per year

PHI: 1 day
REI: 12 hours
Aerial/Drone Application: Depends on formulation.

Important Notes:

  • Minimum retreatment interval: 5 days.
  • 7-day minimum retreatment interval for SWD.
  • High runoff potential after application.
  • Highly toxic to bees if sprayed directly.
  • Potential for phytotoxicity at reduced rates.
  • See label for dilute vs. concentrated spray.
  • Not systemic (NS).
  • 3-day environmental persistence.
  • Apply at 10 day intervals for blueberry maggot fly.

Human & Environmental Risk:

  • Extremely toxic to fish.
  • Extremely toxic to bees.
  • Moderately toxic to birds.
  • Moderately toxic to people.

Target Pest(s):

  • Blueberry maggot fly
  • Spanworm larvae
  • Flea beetle
  • Strawberry root worm
  • Spotted winged drosophila

Spotted Winged Drosophila Control: Very Effective
Active Ingredient(s): Phosmet
Signal Word: Warning

Rate:

  • 1.3 lb
  • Maximum: 5 applications, 5 1/8 lb (3.63 lb ai) per year

PHI: 3 days
REI: 3 days
Aerial/Drone Application: Not permitted.

Important Notes:

  • Apply at 7–10 day intervals.
  • Highly toxic to bees if sprayed or if they contact treated foliage up to 7–10 days after spraying.
  • Do not spray 10–14 days prior to bloom.
  • Not systemic (NS).
  • 10-day environmental persistence.

Human & Environmental Risk:

  • Extremely toxic to fish.
  • Extremely toxic to bees.
  • Moderately toxic to people.

Group 3

Target Pest(s):

  • Blueberry maggot fly
  • Spanworm larvae

Active Ingredient(s): Esfenvalerate
Signal Word: Warning

Rate:

  • 4.8 to 9.6 oz
  • Maximum: 38.4 oz (0.2 lb ai) per acre per year

PHI: 14 days
REI: 12 hours
Aerial/Drone Application: Can be aerially applied.

Important Notes:

  • Do not apply within 7 days of pollination.
  • Not systemic (NS).
  • 7-day environmental persistence.

Human & Environmental Risk:

  • Extremely toxic to fish.
  • Extremely toxic to bees.
  • Moderately toxic to people.

Group 3A

Target Pest(s):

  • Spotted winged drosophila

Spotted Winged Drosophila Control: Very Effective
Active Ingredient(s): Zeta-cypermethrin
Signal Word: Warning

Rate:

  • 4 oz (4 oz for SWD)
  • Maximum: 24 oz (0.15 lb ai) per acre per year

PHI: 1 day
REI: 12 hours
Aerial/Drone Application: Can be aerially applied.

Important Notes:

  • Apply at least 7 days apart.
  • See 2ee labels for blueberry maggot fly (suppression only) and spotted winged drosophila.
  • Direct spray and residue are highly toxic to bees.
  • Do not use prior to or during bloom.
  • Not systemic (NS).
  • 21-day environmental persistence.

Human & Environmental Risk:

  • Extremely toxic to fish.
  • Extremely toxic to bees.
  • Moderately toxic to people.

Group 4A

Target Pest(s):

  • Blueberry maggot fly
  • Thrips

Active Ingredient(s): Imidacloprid
Signal Word: Caution

Rate:

  • Foliar: 2.1 to 2.8 oz
  • Maximum foliar application: 5 applications, 14 oz (0.5 lb ai) per acre per year.

PHI: 3 days
REI: 12 hours
Aerial/Drone Application: Can be aerially applied.

Important Notes:

  • Do not use prior to or during bloom.
  • Highly toxic to bees if used as a foliar spray during bloom.
  • Apply at least 7 days apart.
  • Foliar: for sprout application during emergence of thrips and tip midge.
  • Systemic (S).
  • 7-day environmental persistence.

Human & Environmental Risk:

  • Extremely toxic to bees.
  • Extremely toxic to birds.
  • Moderately toxic to people.

Target Pest(s):

  • Blueberry maggot fly
  • Flea beetle
  • Spotted wing drosophila

Spotted Winged Drosophila Control: Moderately Effective
Active Ingredient(s): Acetamiprid
Signal Word: Caution

Rate:

  • 4.5 to 5.3 oz (5.3 oz for spotted wing drosophila)
  • Maximum: 5 applications, 26.7 oz (0.5 lb ai) per acre per year

PHI: 1 day
REI: 12 hours
Aerial/Drone Application: Can be aerially applied.

Important Notes:

  • Do not apply more than once every 7 days.
  • Add 1 lb per acre sugar to spray tank to enhance performance for spotted wing drosophila only.
  • Toxic to bees exposed to direct treatment.
  • Do not apply while bees are actively visiting treatment area.
  • Systemic (S).
  • 7-day environmental persistence.

Human & Environmental Risk:

  • Moderately toxic to bees.

Target Pest(s):

  • Blueberry maggot fly
  • Flea beetle
  • Spotted wing drosophila

Spotted Winged Drosophila Control: Moderately effective
Active Ingredient(s): Acetamiprid
Signal Word: Caution

Rate:

  • 1.7 to 3.0 oz
  • Maximum: 2 applications, 6 oz (0.26 lb ai) per acre per year

PHI: 1 day
REI: 12 hours
Aerial/Drone Application: Can be aerially applied.

Important Notes:

  • Do not apply more than once every 7 days.
  • Toxic to bees exposed to direct treatment.
  • Do not apply while bees are actively visiting treatment area.
  • Systemic (S).
  • 7-day environmental persistence.

Human & Environmental Risk:

  • Moderately toxic to bees.

Target Pest(s):

  • Blueberry maggot fly
  • Flea beetle
  • Spotted wing drosophila
  • Thrips

Spotted Winged Drosophila Control: Moderately effective
Active Ingredient(s): Imidacloprid
Signal Word: Caution

Rate:

  • Foliar: 4.8 to 6.4 oz
  • Maximum: 5 applications, 32 oz (0.5 lb ai) per acre per year

PHI: 3 days
REI: 12 hours
Aerial/Drone Application: Can be aerially applied.

Important Notes:

  • Apply at least 7 days apart.
  • Rotate to another mode of action after 3 applications.
  • Do not apply foliar after soil application of any Group 4A product.
  • Avoid use prior to and during bloom.
  • Highly toxic to bees.
  • Systemic (S).
  • 7-day environmental persistence.

Human & Environmental Risk:

  • Extremely toxic to bees.
  • Extremely toxic to birds.

Target Pest(s):

  • Thrips
  • Blueberry maggot fly
  • Flea beetle
  • Spotted wing drosophila

Spotted Winged Drosophila Control: Moderately effective
Active Ingredient(s): Imidacloprid
Signal Word: Caution

Rate:

  • Foliar: 2.4 to 3.2 oz
  • Maximum: 5 applications, 16 oz (0.5 lb ai) per acre per year

PHI: 3 days
REI: 12 hours
Aerial/Drone Application: Can be aerially applied.

Important Notes:

  • Apply at least 7 days apart.
  • Rotate to another mode of action after 3 applications.
  • Avoid use prior to and during bloom.
  • Highly toxic to bees.
  • Systemic (S).
  • 7-day environmental persistence.

Human & Environmental Risk:

  • Extremely toxic to bees.
  • Extremely toxic to birds.

Group 4D

Target Pest(s):

  • Blueberry maggot fly
  • Thrips

Active Ingredient(s): Flupyradifurone
Signal Word: Caution

Rate:

  • 10.5 to 14 oz
  • Maximum: 28.0 oz (0.365 lb ai).

PHI: 3 days
REI: 4 hours
Aerial/Drone Application: Can be aerially applied.

Important Notes:

  • Apply at least 7 days apart.
  • See 2ee label for thrips.
  • Human dermal toxicity is moderate.
  • Systemic.

Human & Environmental Risk:

  • Moderately toxic to people.
  • Moderately toxic to bees.

Group 5

Target Pest(s):

  • Spanworm larvae
  • Strawberry rootworm
  • Spotted wing drosophila

Spotted Winged Drosophila Control: Effective
Active Ingredient(s): Spinosad
Signal Word: N/A

Rate:

  • 4 to 6 oz
  • Maximum: 6 applications (3 for thrips), 29 oz (0.45 lb ai total for all spinosad products)

PHI: 1 days
REI: 4 hours
Aerial/Drone Application: Can be aerially applied.

Important Notes:

  • Allowed for organic production. 
  • Toxic to bees up to 3 hours following treatment. Once it dries on foliage, toxicity is low.
  • Apply at least 6 days apart; after 2nd application rotate to products other than Group 5.
  • May be used with adjuvants.
  • See supplemental label for reduced PHI for spotted wing drosophila suppression.
  • Not systemic.
  • 1.5 day persistence

Human & Environmental Risk:

  • Extremely toxic to fish.
  • Extremely toxic to bees.

Target Pest(s):

  • Blueberry maggot fly

Active Ingredient(s): Spinosad
Signal Word: Caution

Rate:

  • 10 to 20 oz
  • 1:1.5 product to water ratio
  • Maximum: 5 applications; 0.45 lb ai total for all spinosad products

PHI: 1 days
REI: 4 hours
Aerial/Drone Application: Can be aerially applied.

Important Notes:

  • Allowed for organic production.
  • Specialized application equipment is required.
  • Apply every 7-14 days.
  • Do not rotate with other Group 5 products.
  • Toxic to bees if sprayed directly.
  • Not systemic.
  • 1.5 day persistence.

Human & Environmental Risk:

  • Extremely toxic to fish.
  • Extremely toxic to bees.

Target Pest(s):

  • Blueberry maggot fly
  • Flea beetle
  • Strawberry root worm
  • Spotted wing drosophila

Spotted Winged Drosophila Control: Very effective
Active Ingredient(s): Spinetoram
Signal Word: Caution

Rate:

  • 3 to 6 oz
  • Maximum: 6 applications (3 for thrips); 19.5 oz (0.305 lb ai)

PHI: 3 Days
REI: 4 Hours
Aerial/Drone Application: Can be aerially applied.

Important Notes:

  • Do not apply more than once every 6 days, and no more than two consecutive applications of any Group 5 insecticide.
  • Highly toxic to bees if sprayed or come into contact with wet treated foliage.
  • If foliage is dry, toxicity is very low to bees.
  • Do not rotate with spinosad products.
  • Not systemic.
  • 5 day persistence.

Human & Environmental Risk:

  • Extremely toxic to fish.
  • Extremely toxic to bees.

Group 11

Target Pest(s):

  • Spanworm larvae

Active Ingredient(s): Bacillus thuringiensis
Signal Word: N/A

Rate:

  • Read label.

PHI: Read label.
REI: 4 hours
Aerial/Drone Application: Can be applied aerially.

Important Notes:

  • May use when bees are present.
  • Most effective on small early instar blueberry spanworm larvae.
  • This bio-insecticide is not effective against winter moth larvae.
  • Do not apply within 300 ft of any threatened or endangered Lepidoptera.
  • Product(s) may be OMRI listed, e.g. Javelin WG.
  • Not systemic.
  • 3 day persistence.

Group 18

Target Pest(s):

  • Spanworm larvae

Active Ingredient(s): Methoxyfenozide
Signal Word: Caution

Rate:

  • 10 to 16 oz
  • Maximum: 3 applications; 48 oz (0.75 lb ai)

PHI: 7 days
REI: 4 hours
Aerial/Drone Application: Can be aerially applied.

Important Notes:

  • For caterpillar control.
  • Do not apply more than once every days.
  • Spreaders/binders may help maximize coverage.
  • Can be used just prior to bloom without detrimental effects bees.
  • Drift and runoff from applications of this product may be hazardous to sensitive aquatic invertebrates in water bodies adjacent to treatment area.
  • Not systemic.
  • 15 day persistence

Group 28

Target Pest(s):

  • Blueberry maggot fly
  • Spotted wing drosophila

Spotted Winged Drosophila Control: Effective
Active Ingredient(s): Cyantraniliprole
Signal Word: Caution

Rate:

  • 13.5 to 20.5 oz
  • Maximum: 62 oz (0.4 lb ai)

PHI: 3 days
REI: 12 hours
Aerial/Drone Application: Can be aerially applied.

Important Notes:

  • Rotate with products with different modes of action; minimum interval between treatments is 5 days.
  • Direct contact and exposure to residue is toxic to bees.
  • Systemic.
  • 14 day persistence.

Human & Environmental Risk:

  • Moderately toxic to people.
  • Extremely toxic to bees.

Target Pest(s):

  • Spotted wing drosophila

Spotted Winged Drosophila Control: Very effective
Active Ingredient(s): Cyclaniliprole
Signal Word: Caution

Rate:

  • 8.2 to 11.0 oz
  • Maximum: 33 oz (0.22 lb ai)

PHI: 1 day
REI: 4 hours
Aerial/Drone Application: Can be applied aerially.

Important Notes:

  • This product is highly toxic to bees and other pollinating insects exposed to direct treatment or to residues in/on blooming crops or weeds.
  • Make no more than 3 applications per year.
  • The minimal interval between treatments is 5 days.
  • Systemic.
  • 14 day persistence.

Human & Environmental Risk:

  • Moderately toxic to people.
  • Extremely toxic to bees.

Group M

Target Pest(s):

  • Flea beetle

Spotted Winged Drosophila Control:
Active Ingredient(s): Beauveria bassiana
Signal Word: Caution

Rate:

  • 0.5 to 1.0 qt
  • Maximum: none

PHI: 0 days
REI: 4 hours
Aerial/Drone Application: Can be aerially applied.

Important Notes:

  • Apply at 5-10 day intervals in the evening as sunlight destroys spores.
  • Clean all fungicide residues from tank as they will destroy the Beauvaria spores and inactivate the product.
  • Not systemic.
  • 2 day persistence.

Human & Environmental Risk:

  • Extremely toxic to people.

Unknown Group

Target Pest(s):

  • Spotted wing drosophila

Spotted Winged Drosophila Control: Slightly effective
Active Ingredient(s): neem, azadirachtin
Signal Word: Caution

Rate:

  • Foliar: 10 to 16 oz (see exceptions) + COC 1% v/v (Azaguard rate only)
  • Maximum: None; 22.5 oz AzaGuard per application (0.75 lb/20 g ai all azadirachtin per application).

PHI: 0 days
REI: 4 hours
Aerial/Drone Application: Can be aerially applied.

Important Notes:

  • Effective on spotted wing drosophila under low to moderate pressure; once spotted wing drosophila numbers build, switch to another product.
  • When infestation is heavy or canopy dense, use up to 2x rate, not to exceed 22.5 oz/a/application.
  • Use ½ rate when combining with other insecticides.
  • Do not mix with highly alkaline products or exceed mix pH 7.
  • Label recommends 2-3 applications at 7-10 day intervals.
  • Not systemic.
  • 7 day persistence.

Footnotes

Group Number

To reduce the likelihood of insecticide resistance developing in target pests, growers should rotate between insecticides with different group numbers in the growing season, ideally using multiple group numbers. Products with the same group number should not be used in consecutive sprays.