How to Compare Carpenter Bees to Bumble Bees

Both bumble bees and carpenter bees pollinate flowers, but carpenter bees have become nuisances by nesting in the soft, untreated woods they find around houses and yards. A nest is not too damaging at first, but years of nesting in the same spot can cause structural damage. Here's how you can discern the difference between the ground-nesting bumble bee and the wood-boring carpenter bee.

Instructions

1. Check your house and yard for worn or untreated wood surfaces. Carpenter bees nest in trees and wood structures. Western carpenter bees choose the hard wood of the oak, the eucalyptus and redwood. Eastern carpenter bees prefer softer woods like cedar, cypress, pine, and fir. They do not bore into painted woods or woods with bark.

2. Watch the bees flying around your yard and garden. Both bumble bees and carpenter bees hover around flowers collecting pollen and nectar. While bumble bees tend to stay in your yard, carpenter bees will be fly around the eaves and windowsills of your house, common nest sites for carpenter bees.

3. Watch where the bees go to nest. Bumble bees nest in found spaces, often in the ground, but do not dig or bore nests. Carpenter bees bore into wood and build their nests there. They either create or use an existing hole as an entrance to their nests.

4. Note if they behave aggressively. Bumble bees keep to the flowers. Carpenter bees, whether they are aggressive or just curious, habitually buzz around your head. This behavior is annoying, but not dangerous. These are male bees and have no stingers. Only the female has a stinger, and she stays with the nest, only stinging if threatened.

5. If you can get a close look, inspect their abdomens, back legs and stingers. The abdomen of the carpenter bee is hairless, shiny and black. The abdomen of the bumble bee is covered in yellow and black hairs, giving it a fuzzy appearance. The bumble bee also has large pollen baskets on its back legs and a visible stinger.

Tips & Warnings

• Unlike honey bees, bumble bees can sting repeatedly. The female carpenter bee has a stinger. Though mostly docile, it is her job to guard the nest.

References

• University of Kentucky
• Ohio State University
• Pennsylvania State University

Resources

• BumbleBee.org