You have no idea where did you get that holes on the deck? That might be from Carpenter bees. Carpenter bees are large, fuzzy bees that bore holes in unfinished wood to nest and lay eggs. Carpenter bees prefer to have their nests in soft, unpainted wood. Softer woods – like pine, cedar, redwood, and cypress – are more attractive for nests.
The holes typically go inward for about an inch, then the tunnel turns and follows the grain of the wood for about six more inches.
Carpenter bees don’t systematically destroy a structure like termites or carpenter ants.
However, if the infestation is extensive or has been going on for years, the number of tunnels can cause problems, including:
- Structural Damage: A lot of tunnels can weaken wood over time.
- Water Damage: If water enters the tunnels, it can speed the wood rotting.
- Stains: Feces of carpenter bees can stain wood.
How to Prevent Carpenter Bee Damage
- Paint: Carpenter bees likes unfinished woods. You will secure the deck by painting all surfaces (including the backs and undersides of boards) with a sealing primer and at least two coats of paint. Stains and varnishes are less effective, but any coating is better than bare wood.
- Non-Wood Covering: If the problem is unrelenting, you may need to look into non-wood siding and trim options, such as aluminum, vinyl, fiber cement, or masonry.
- Fill Cracks: Before painting or sealing, fill all cracks, nail holes, divots, and splintered wood with caulking or putty; since these are attractive starting places for bees.