During the spring, people often notice large, black bees hovering around the outside of their homes. These are likely to be carpenter bees, named for their habit of excavating holes in wood, in order to rear their young. Carpenter bees prefer unpainted, weathered wood, especially softer varieties such as redwood, cedar, cypress and pine. Painted or pressure-treated wood is much less susceptible to attack. Common carpenter bee nesting sites include eaves, rafters, fascia boards, siding, wooden shake roofs, decks and outdoor furniture.
Though seldom as destructive as termites, carpenter bees can cause cosmetic and structural damage. Female carpenter bees excavate new tunnels in wood for egg laying, or enlarge and reuse old ones. Significant damage can occur when the same pieces of wood are infested year after year. Holes in the wood surface also facilitate moisture intrusion, rot and decay.
Yellowjackets are social insects that live in nests or colonies with up to 4,000 workers. They are most active in the late summer and early autumn when a colony is at its peak. Yellowjackets feed on sweets and proteins, and therefore these pests commonly invade outdoor events. Yellowjackets can be found anywhere humans are found. They build paper carton nests out of chewed up cellulose, which are usually found in the ground or in cavernous areas such as eaves and attics.
Yellowjacket stings pose significant health threats to humans, as they are territorial and will sting if threatened. They are known to sting repeatedly and can cause allergic reactions. Yellowjackets and other stinging insects send over 500,000 people to the emergency room each year.
The European paper wasp, Polistes dominula, gains its name from the paper it makes to build its umbrella-shaped nests, often found under eaves across North America. While less aggressive than their yellowjacket cousins, from whom they subtly differ in appearance, paper wasps will deliver a painful sting if their nests are threatened. Paper wasps will occasionally feed on nectar and fermenting substances, but also prey on insects as a protein source for their young. That makes human food especially attractive as summer ends and insect prey, such as aphids and caterpillars, become rare.
They’re looking for protein and sugar. That’s why they show up at your house, zoom around your garbage can, and take a bite out of your sandwich. Paper wasps can be hard to eliminate from homes and yards, because they’re different from other wasp species. They’re not attracted to the same things that yellowjackets and hornets are.