Carpenter bees live on every continent except Antarctica, nesting inside wood or plant stems rather than in hives or underground. With nearly 400 species worldwide, they show up in backyards, forests, and wild grasslands, but they’re especially common in tropical and subtropical regions. If you’re finding them around your home, they’re almost certainly tunneling into exposed, unpainted wood on your house or outbuildings.
Geographic Range
Large carpenter bees (the ones most people encounter) are found across the Americas, Europe, Asia, Africa, and Australia. The greatest diversity is in the tropics: over 100 species live in Central and South America alone, with major concentrations in the Amazon basin and the subtropical mountains of eastern South America. In Asia, distinct lineages spread westward into the Middle East and Europe, while others diversified across Southeast Asia and the Pacific islands.
In North America, the eastern carpenter bee is the most familiar species. Its range stretches from Florida north to southern Ontario, covering a large swath of the eastern United States and southeastern Canada. A handful of other species occupy the southwestern U.S. and the Pacific coast. These North American species descended from tropical ancestors, and only a few derived lineages ever adapted to cooler northern climates.
Where They Nest in Nature
Unlike honeybees or bumblebees, carpenter bees don’t build wax combs or live in colonies with thousands of workers. Each female excavates her own tunnel in wood or, for smaller species, inside the soft pith of dead plant stems. Large carpenter bees target sound, undecayed wood that still has structural integrity. They avoid rotten wood because it doesn’t provide the stable walls their tunnels need.
In forests, they bore into dead limbs still attached to living trees, fallen logs, and standing dead trunks. Small carpenter bees (the genus Ceratina) take a different approach entirely. These tiny, often metallic-green bees nest inside the pithy centers of dead plant stalks. In northwestern Pakistan, for example, one species nests exclusively in dead stalks of Ravenna grass. If you leave dried flower stems standing in your garden over winter, you may be providing exactly the kind of habitat small carpenter bees need.
Where They Nest on Houses
The most common nesting sites on buildings are eaves, rafters, fascia boards, siding, wooden shake roofs, decks, and outdoor furniture. Carpenter bees strongly prefer bare, unpainted, unfinished wood. They also readily attack softwoods like southern yellow pine, white pine, redwood, cedar, Douglas fir, and cypress, along with certain hardwood-adjacent species like mimosa, mulberry, ash, and pecan. They generally avoid true hardwoods.
The entrance hole is a nearly perfect circle about half an inch in diameter. The tunnel goes straight into the wood for a few inches, then makes a sharp 90-degree turn and follows the grain of the wood lengthwise. A single tunnel can extend six inches or more, and over multiple generations, these galleries branch and grow considerably longer. You’ll often notice coarse sawdust (called frass) piled below the entrance hole, along with yellowish staining on the wood surface from bee excrement.
Why They Return to the Same Spot
Carpenter bees reuse the same nests year after year, and this is one reason damage to wooden structures compounds over time. Excavating a brand-new tunnel takes enormous energy and cuts into the number of offspring a female can raise in a single season. A bee who inherits or takes over an existing nest can skip much of that labor and devote more resources to laying eggs and provisioning brood cells with pollen.
When nesting sites are plentiful, each female typically occupies her own tunnel. But when good wood is limited, small groups cluster together, and competition for established nests intensifies. Subordinate females sometimes wait for a nest owner to die rather than strike out on their own, because the reproductive payoff of inheriting a pre-built home outweighs the risk of starting fresh. Carpenter bees can live several years, long enough for this waiting strategy to pay off. The result is that a single board on your deck or fascia can host an expanding network of tunnels that grows more elaborate with each generation.
Where They Spend the Winter
Adult carpenter bees overwinter inside their wood tunnels. As temperatures drop below roughly 40 to 50°F, they become inactive and stay sealed inside the gallery until spring warmth draws them out. New adults that emerged in late summer often hibernate in the same nest where they developed. This is another reason old nests remain occupied: they double as winter shelters. In spring, females emerge, mate, and either expand their inherited tunnel or begin searching for new nesting wood nearby.
Small carpenter bees overwinter in a similar fashion, tucked inside dead plant stems. Leaving dried flower stalks and ornamental grass stems intact through winter provides overwintering habitat for these species, which are effective pollinators of garden plants and crops.
Spotting a Nest on Your Property
The easiest way to find carpenter bee nests is to watch for the bees themselves in spring. Males hover aggressively near nesting sites, sometimes dive-bombing people who walk by, but they lack stingers and are harmless. Females are the ones doing the drilling, and you can sometimes hear them chewing wood from several feet away.
Look for the telltale half-inch entry holes on the undersides of deck rails, porch ceilings, fence posts, pergolas, and the exposed ends of joists. Sawdust accumulating on surfaces below these holes is a reliable sign. Sheds, barns, and playsets made of untreated softwood are frequent targets. Painted or varnished wood is far less attractive to them, so surface finishes on exposed wood are one of the most effective deterrents.