Big, bold, and buzzing—three innocuous words describing the frightening and seemingly “aggressive” force behind the Carpenter bee. Carpenter bees are one of the most feared springtime pests in the DMV. These three simple facts about them might surprise you.
Those familiar buzzing carpenter bees seem ever-present once they’ve burrowed into your yard. But how long do these insects actually hang around each year? The answer lies in understanding the carpenter bee’s annual life cycle
Carpenter bees go through a predictable seasonal cycle tied to stages of development, feeding, reproduction, and hibernation. Knowing their behavior patterns provides insights into managing them without harming these important pollinators.
The Carpenter Bee Year Explained
Carpenter bees have a roughly one-year lifecycle from egg to adult. Here are the key events in a typical carpenter bee calendar year:
Spring
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Late March – April: Adult carpenter bees emerge from hibernation.
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May Mating occurs, followed by nesting and egg-laying by fertilized females.
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June – July: Larvae hatch and feed in nest galleries on bee bread provisions.
Summer
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July – August Larvae transform into pupae then into adults.
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August – September: New adult generation emerges from nests. They feed on and pollinate flowers.
Fall
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September – October: Bees stock nests with food supply for winter and seal entrance holes.
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November: Carpenter bees enter hibernation, sheltering in nest galleries.
Winter
- December – February: Bees remain dormant in nests through winter months.
Lingering All Season
Carpenter bees have a nearly year-round presence once established:
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Spring: Overwintered adults become active starting in early spring.
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Summer: New bees continue buzzing about through late summer after emerging.
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Fall: Adults remain busy stockpiling food before hibernating.
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Winter: Bees shelter inactive in nests, emerging periodically during warm spells.
Why Do Carpenter Bees Stick Around?
Several key facts about carpenter bee biology explain their enduring presence:
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Reusing nests: Carpenter bees often reuse the same nests year after year, holes permitting. This conserves energy compared to excavating new nests each season.
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Long life: Female carpenter bees may live for several years, returning to their nesting site annually.
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Extended activity: Adults are active from spring through fall, spanning 5-6 months. Their life isn’t confined solely to summer.
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Overwintering: Rather than migrating away, carpenter bees hibernate inside their nest galleries during winter. This allows them to emerge promptly in spring.
Do Carpenter Bees Die Off in Winter?
Carpenter bees don’t completely die off in winter. Their populations do decline but some hardy bees survive:
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Males and older female bees typically die after mating and laying eggs.
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Fertilized new females overwinter in nests to start the next generation.
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Overwinter survival rate depends on weather severity. Warmer winters see more bees emerging in spring.
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Enough bees endure winter for mating and reproduction. But populations are smaller in early spring compared to fall.
Managing Seasonal Carpenter Bee Activity
You can use the carpenter bee’s natural seasonal cycle to guide management:
Spring
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Inspect wood for new nests as overwintered bees become active.
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Use preventive sealing, traps, and deterrents before nest excavation begins.
Summer
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Monitor for emerging new adults and apply bee-safe treatments to deter nesting.
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Discourage nesting with noisemakers, resin barriers, and wood treatments.
Fall
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Vacuum remaining bees before they hibernate to reduce next year’s population.
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Seal entrances thoroughly so bees can’t return in spring.
Winter
- Repair and replace damaged wood during dormant season when bees are inactive.
Why Carpenter Bees Are Beneficial
Despite being deemed pests, carpenter bees play vital ecological roles:
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Pollination: Carpenter bees pollinate wildflowers, gardens, and some crops as they feed on nectar and pollen.
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Biodiversity: Around 500 carpenter bee species populate diverse global regions, indicative of environmental adaptability.
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Research value: Scientists study carpenter bees to uncover new insights into ecology, genetics, behavior, biomechanics, and pollination.
Achieving Balance with Carpenter Bees
The optimal solution is integrated management that prevents structural damage but sustains carpenter bee populations:
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Deter bees from nesting on vulnerable human structures through sealing, traps, and repellents.
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Provide alternative nesting sites like untreated scrap wood away from your home.
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Avoid widespread use of pesticides lethal to bees and other pollinators.
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Learn to coexist with this vital species that’s fascinating to observe.
The Takeaway on Carpenter Bee Seasonality
Carpenter bees have evolved a reproductive strategy of sticking around by overwintering in nests and reusing holes year after year. Their annual cycle means managing them requires vigilance through spring, summer, and fall. But it also offers opportunities to protect your home without destroying vital pollinating insects. Understanding their seasonal biology is key to implementing an informed long-term management plan.
Excavate to build a nest.
No other female bee builds a nest for her young like the carpenter bee, and she wouldn’t be taking her job seriously without a tool belt fit for a woodworker!
She is the only one who can grind her teeth against the wood to make nearly perfect holes the size of dime and galleries 6 to 8 inches wide where she can lay her eggs.
The female carpenter bee will usually choose wood that isn’t painted or has been weathered. She will also go back to the same nesting site year after year. Who wouldn’t after all that work?.
Tip: If you discover coarse, sawdust-like material collecting on surfaces, you might have a carpenter bee problem.
Carpenter bee feces: It Stains.
See those yellow-brown spots on your house’s siding, maybe under the gutters or the eaves? They are caused by carpenter bee poop, and they are very hard to get rid of.
Power washing doesn’t always get rid of carpenter bee poop. Finding yellow-brown stains on the side of your house, on the other hand, is a good sign that you have a problem with carpenter bees. Look high and low for this telltale sludge in an effort to locate carpenter bee nesting sites.
How Much DAMAGE Can CARPENTER BEES Cause?! (What To Do About Carpenter Bees/How To Get Rid?)
FAQ
What makes carpenter bees go away?
How long do carpenter bees stay active?
Why are carpenter bees hovering around my house?
Should I leave carpenter bees alone?
How long do carpenter bees stay in a nest?
After approximately three months of development, carpenter bees emerge, typically in late summer. These newly developed bees remain in the nest for several weeks, provisioning old tunnels with pollen and nectar. Once they leave the nest, the siblings disperse, each venturing to construct their own nest.
How long do carpenter bees live?
The”expected” lifespan of a carpenter bee is one year. However, the bees may live for up to three years, with some having two generations living in the same nests. We have an in-depth article that compares the life cycles of carpenter bees with both honey bees and bumblebees. The article is Carpenter Bees Vs Bumblebees Vs Honey Bees.
Do carpenter bees build nests?
When not constructing nests, carpenter bees engage in buzz pollination and collect food for the winter. As masterful architects, carpenter bees intricately carve out nests within wood. These nests, which rarely change locations once established, consist of tunnels and chambers where eggs and food are stored.
How long does it take a carpenter bee to build a nest?
To build their nests, they first drill a hole of 1/2 inch in diameter in wood, preferably thick wood of more than 2 inches width. It takes 5 to 6 days for the female carpenter bee to drill and excavate just 1 inch of wood.
How big do carpenter bees get?
Carpenter bee sizes vary, and they can be anywhere between a half and one inch long. Carpenter bees don’t live in colonies though, and the differences between male and female bees are superficial. Females have black heads, and males have white markings on their faces. Other than that, they’re almost exactly the same—even in size.
How long does a carpenter bee lay eggs?
The female carpenter bee will lay her eggs in the nest, along with a food supply of pollen and nectar. The eggs hatch into larvae in about 2 weeks. 4. Larval Development The larvae feed on the food supply for about 6 weeks.