Carpenter Bee Treatment

ChemicalLicense Required
Effectiveness:
Cost Level
Low
Environmental Impact
Low
Resistance Risk
Low
Target Pests
1 species

Target Pests (1)

Common NameScientific NameCategory
Carpenter BeeXylocopa spp.Stinging Insects

Application Method

Treat active carpenter bee tunnels by applying insecticide dust (deltamethrin, permethrin, or boric acid) directly into entrance holes using hand duster or puffer. Insert duster tip into hole and apply several puffs of dust deep into gallery. Dust will contact bees and coat tunnel walls providing residual control. DO NOT seal holes immediately - allow bees to contact dust and distribute it through galleries for 24-48 hours. After treatment period, plug entrance holes with wood putty, caulk, or wooden dowels to prevent reuse and new infestations. Paint or stain all bare wood as carpenter bees prefer untreated, weathered wood. For active infestations, treat in spring when adult bees emerge and again in late summer. May also apply residual surface spray to wood surfaces where bees are boring.

Timing

Treat in spring (April-June) when adult bees actively boring new tunnels. Second treatment in late summer (July-August) when new generation emerges. Preventative surface treatments best applied in early spring before bee activity.

Frequency

Treat tunnels as soon as boring activity observed. Annual preventative treatments recommended for structures with history of infestation. Reapply surface treatments annually to bare wood.

Preparation Required

Identify all entrance holes (perfectly round, 1/2 inch diameter). Note fresh coarse sawdust below holes indicating active boring. Inspect eaves, fascia, siding, deck rails, and wooden outdoor furniture.

Follow-up Required

Return after 48 hours to seal treated holes. Monitor for new holes throughout season. Recommend painting/staining bare wood to prevent future infestation. Remove old weathered wood that attracts bees.

Safety Precautions

  • Male carpenter bees are aggressive but cannot sting; females rarely sting
  • Wear eye protection when applying dust overhead
  • Use non-staining dust formulations on finished wood
  • Avoid treating during peak pollinator activity hours
  • Follow label instructions for dust application
Important Disclaimer: The information provided in this knowledge base is for educational and reference purposes only. Pest management professionals should always consult current product labels, Safety Data Sheets (SDS), manufacturer instructions, and applicable local, state, and federal regulations as the definitive source of truth. Product formulations, application methods, safety requirements, and regulations may change over time. This information may be out of date and should not replace professional judgment, proper training, or required licensing and certifications.