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carpenter bee in nature

AUBURN UNIVERSITY, Ala. – Nature’s noisy woodworkers are buzzing by the bunches in Alabama. Carpenter bees can easily overwhelm homeowners as they arrive at doors by the day to make their unwelcome habitats in homes, sheds, mailboxes and other wooden structures. To safely and appropriately conquer these pests, Alabama Cooperative Extension System entomologists encourage homeowners to learn more about their springtime foes.

What are carpenter bees?

Most carpenter bees seen in Alabama are of the species, Xylocopa virginica. During the winter, carpenter bees spend their time in underground nests in dead trees and wood piles. When temperatures consistently rise (often in spring) the bees will emerge and begin to look for a new nesting site. These bees remain active through the summer and are often found around homes.

Their natural instinct to bore one-half-inch holes give these bees their name. However, no maintenance call is necessary to summon these carpenters.

Carpenter bees are natural pollinators and provide numerous benefits to the environment. However, they habitually live in close proximity to humans and can deal progressive damage to wood structures. These insects have the potential to affect homes, especially when they repeatedly colonize in exposed wood without control.

Without Invitation

“Female carpenter bees are the ones causing the damage,” said Alabama Extension Entomologist Xing Ping Hu. “To lay eggs, females drill into dry wood on home features such as siding, fascia boards, porch window trim, porch ceilings, fence, decks, outdoor furniture and other wooden surfaces.”

The female carpenter bee will chew a perfectly-round entrance, roughly the size of a dime, into the sides of wood. These entrances are typically an inch in depth, then make a turn at a 90-degree angle to excavate a gallery.

Their galleries typically follow wood grain which serves as a path of least resistance. Inside each gallery, females construct six to 14 cells. In each cell are provisions of mixed pollen and nectar, which will be food for her offspring. Eggs are placed on the food and cells are sealed shortly after with chewed wood pulp. After hatching, larvae will grow into adults and will chew through the cell partition–emerging in late summer.

Signs of Carpenter Bee Infestation

There are multiple signs that indicate whether your home has uninvited, buzzing guests. Look for these giveaways when searching around property.

  • Carpenter bees hover nearby and around your building and structures—they are looking for nesting sites
  • Coarse sawdust that collects beneath excavated cavities during the spring
  • Round and smooth holes in size of a dime on exterior wood surfaces
  • Unsightly stains caused by falling bee waste around the circular entrance hole
  • Noticing a buzzing or burrowing sound coming from within the wood

The Most Common Question

One of the most common questions regarding carpenter bees (and most flying insects) is whether it will bite or sting. Hu said the good news is that bites are highly unlikely. However, it is possible if the situation is right.

Females have a stinger, but are only defensive when directly provoked. Carpenter bees that are acting in a show of flying aggression are most likely males that are behaving in defense of territory. Male carpenters bees do not have a stinger and are considered harmless. Hu said the simplest way to tell the difference is that males have a white or yellow blaze on their face while females have a dark face.

Cousins, Not Siblings

A close family member of the carpenter bee is the bumble bee. Widely known for their stinging nature and similar color pattern, bumble bees are often mistaken for their larger cousins.

“An easy way to tell these two apart is by looking at their abdomens,” Hu said. “The abdomen of carpenter bee is shiny, black and hairless. The bumble bee is covered with soft, fuzzy hairs patterned with distinct black and yellow stripes.”

The contrasts continue when learning more about these two bees. Each has their own habits and can be distinguished from afar after picking up these cues.

  • Carpenter bees are solitary bees, less defensive of their nest sites. Bumble bees are social and extremely defensive when their nest site is disturbed.
  • Carpenter bees tend to stick closely to their preferred wooden environment. Bumble bees are likely found around blossoming plants and flowers.
  • Carpenter bees fly in a more erratic way. It may appear like carpenter bees are chasing one another rather than flying together in harmony, while bumble bees fly leisurely together.
  • Carpenter bees carve their own tunnels and nest in above-ground wood materials. Bumble bees live in social colonies, usually nesting in the ground.

Control Methods


Timing is the most important component of carpenter bee control because the goal is to avoid nesting damage. The best time to treat and prevent carpenter bees is early spring. Homeowners should seal all openings in wood in order for bees to be deterred from property.

People shouldn’t eliminate all of the bees in the yard since they are important pollinators. The best time to intervene is before the females lay eggs in their tunnels.

Repellants and Deterrents

Painting surfaces is a proven deterrent to carpenter bee activity. Unfortunately, painting or placing polyurethane on wood decks or log homes is often not a desirable option. Wood stains also provide little repellant. Products with essential oil components can deter carpenter bees from carving tunnels or abandoning the excavated nest.

If possible, all severely damaged wood should be removed and replaced with chemical pressure-treated wood to prevent nest construction. Property owners should consider the use of synthetic sidings rather than wood sidings.

It is often necessary to control carpenter bees that are causing damage. Sealing entrance holes with caulking or expanding foam is only half the work. These measures will not work if the holes are not treated with a pesticide.

Trapped adult carpenter bees can chew through drywall mud and caulk while escaping and excavate new openings. Commercial and homemade traps can catch carpenter bees if properly installed, but often do not provide effective control around a structure.


Like with most insects, there is a product commercially made for treating carpenter bee infestation. These products are formulated for dusting, aerosol, foaming and liquid sprays. Insecticides should be considered a last resort of carpenter bee control.

Sprays are often the easiest form of product to apply, but overspray may soak raw wood surfaces. Aerosol sprays, especially foaming formulations with a straw attachment, can be effective if applied to each hole. Dusts are also sold at box stores and can prove to be effective. However, they are messy and difficult to apply without a specially-made applicator.

“Whatever the product used, all label directions must be followed,” Hu said.

Applications yield the best results when performed late in the evening. During this time female bees are typically inside their wood tunnels and less active. While applying, it is also a good idea to wear long-sleeved clothing, chemically-resistant gloves and protective eyewear.

After applying insecticide, people should plug carpenter bee tunnel entrances using trebor plugs, super plugs or wood patch material to stop other insects from invading the holes at a later time.

More Information

To learn more about carpenter bees and their habits, visit the Alabama Extension website at www.aces.edu.