New York State IPM Program

May 27, 2016
by Mary M. Woodsen
Comments Off on All Buzz. No Sting. Carpenter Bees Do Just What Their Name Suggests

All Buzz. No Sting. Carpenter Bees Do Just What Their Name Suggests

When winged assailants — bees, wasps, biting flies — come after us, well, we evolved to run or swat. Now, running makes sense. But swatting?

Sometimes that swatting thing can be an evolutionary dead end. Swat the wrong wasp and next thing you know the entire nest is on your case. An injured (or annoyed) wasp releases “attack pheromones” that tell its kith and kin there’s danger afoot and they’d best do

A gentle observer can get up close and personal with a male carpenter bee.

A gentle observer can get up close and personal with a male carpenter bee.

something about it, fast. If we get in the door quickly enough, too often we run for the wasp spray — not, by the way, a recommended IPM practice except in the most desperate cases. There’s simpler, more timely tricks of the trade. We suggested a couple  in our May 18 post.

Besides, not all creatures that buzz can harm us. That big bumble bee dive-bombing you — well, first off, it’s unlikely it’s a bumble bee. Bumble bees are remarkably gentle. But then, carpenter bees — bumble-bee lookalikes, only lots less furry — usually are too. (And remember: correct identification is key to good IPM.)

Females are busy making nests, but they'll rest on a gently outstretched hand.

Females are busy making nests, but they’ll rest on a gently outstretched hand.

Right now female carpenter bees are (as the saying goes) busy as bees. Whether it’s a horizontal tree branch, a cut log, your porch railing or the eaves of your home, they’re making nests for their young. If you just happen to wander too close, you might end up face to face with a large (and agitated) black and yellow bee — a mate-guarding male.

But in reality there’s nothing to fear.

Why? Because male carpenter bees have no stinger and pose no threat. So why all the fuss? The males are protecting females as they sculpt out nesting sites. If you stand by long enough, you might see several bees buzzing and tumbling with each other. You can identify the males by the pale yellow patch on their face. Two patch-faced tumbling bees — those are males in a tussle. One patch-faced, one without — those bees are mating.

These galleries go with the grain, providing shelter and provisioned with food for larvae en route to becoming adults.

These galleries go with the grain, providing shelter and provisioned with food for larvae en route to becoming adults.

And the females? They have a stinger. But they sting only at need to protect their nest. See some perfectly round holes (about a half-inch across) in your railing? These entryways make a 90-degree bend where females start creating galleries that run with the grain.

What do they eat? Nectar — which makes them useful pollinators. But these bees are smart cookies. When it comes to garden flowers like salvia and penstemon — anything with a slender, tubular flower that these big bees can’t get into — they become nectar robbers. They simply cut a slit at the base of corolla and steal the nectar, presumably leaving the pollination to somebody else.

So next time you’re hazed by a male carpenter bee, just stand quietly by (“quietly” is the operative word) and enjoy the show as they tumble about, mating with flying females or buzzing competing males. Next thing you know, they’re ignoring you entirely.

How to prevent them tunneling into your railings and eaves? After all, left untreated for years, it’s not that good for a home’s structural integrity. Seek no further for IPM’s: Get Rid of Carpenter Bees? Yes Please!

Many thanks to IPMer Matt Frye for providing the original material. Photo credits: male carpenter bee from Female carpenter bee from, Wikimedia Commons. Nesting galleries:

July 8, 2015
by Joellen Lampman
Comments Off on Get Rid of Carpenter Bees? Yes, Please!

Get Rid of Carpenter Bees? Yes, Please!

Carpenter bees are common spring and summer insects in the eastern United States. They first come to attention when males “buzz” or “dive bomb” people passing by and females are seen excavating holes in wooden structures. Like carpenter ants, carpenter bees do not eat wood, but rather use the substrate for nesting. They are important pollinators, but can become a nuisance pest of structures.

Carpenter bee females create galleries or tunnels in dry wood during the spring. Bees bore into the wood, then turn 90 degrees to tunnel along the grain.
Carpenter bee females create galleries or tunnels in dry wood during the spring. Bees bore into the wood, then turn 90 degrees to tunnel along the grain.

Did You Know…?

  • By the numbers: Carpenter bees are solitary insects that do not form colonies, but many females may nest in the same area.
  • Mock attack: If males feel their nests are threatened, they will aggressively pursue and harass, but they have no stinger.
  • Look-alikes: Both carpenter and bumble bees are black and yellow, but bumble bees have fuzzy abdomens while carpenter bees are smooth.
  • Galleries: On average, galleries are 4 – 6”, but tunnels can extend up to 10 feet long.
  • Collateral Damage: In addition to the structural damage caused by carpenter bee tunneling, empty galleries can invite secondary pests such as beetles, moths and scavengers, and even fungal rot when moisture enters openings.

Integrated pest management can help to prevent carpenter bees from redecorating your home. See Get Rid of Carpenter Bees? Yes, Please! fact sheet for more information on carpenter bees and how to manage them.

April 4, 2013
by Mary M. Woodsen
Comments Off on Don’t bee fooled

Don’t bee fooled

April can fool you all month long. Even if your pest-prevention responsibilities lie mostly indoors where frost and rain rarely intrude — a school, an office building, a museum, your home — April has some tricks up her sleeve. Those perimeter  pests, for example: wasps, bees, ants, termites. For many species of wasps and bees, queens are the only ones that survive the winter, so most likely you won’t see them making their solitary way in early spring. Take yellowjackets, paper wasps, and hornets. They’re out there scouting for nest sites — which means you should be scouting for them.


this starter nest is still small

Scope out entryways, porticos, eaves, and attics for small starter nests — it’s far easier to deal with a queen and a half-dozen workers now than a queen and 5,000 workers later. When you see a nest, knock it down with a broomstick, the spray nozzle on a hose, or even your kid’s Super Soaker. Then step on it. If using the broomstick, best done early on chilly mornings — wasps can’t move fast when it’s cool outside.


About yellowjackets — they’re really aggressive in defense of their nests. Not all species nest where you can see them. Some go underground — nesting in abandoned rodent burrows, for instance. Others find sneaky little holes leading into walls or attics. Get professional help — and never swat a yellowjacket (or any other wasp) — it releases alarm pheromones that call its kin to the scene. In the melee that follows you’re likely to get stung way more than you’d like.


Got bumblebees buzzing around your house? Most likely they’re carpenter bees, actually. Bumblebees look fuzzy; carpenter bees have shiny black bellies. Some are all-black.


Watch as they crawl in and out of their perfectly round holes — these bees are nature’s power drill. Though males will dive-bomb you if you move quickly, don’t be fooled (or frightened!): they can’t sting. Females (less often seen) can sting — but only if you work hard to provoke them. Though new nests are small, carpenter bees can do serious damage as subsequent generations bore deeper into wood to rear their young in turn. How to cope? Start here.


Worried you’ve got termites? They might be ants instead. And both termites and ants can swarm on warm spring days — maybe making you think you’ve got some kind of weird bee instead. But those wings are temporary.


Here’s how to tell termites and ants apart. Termites seem to have just two body parts: rounded heads with straight antennas and cigar-shaped bodies. Ants, au contraire, have three distinct body parts and (more distinctly yet) narrow-waisted hourglass figures. Note their bent antennae, too. Most ants are an annoyance and no more … but carpenter ants can remodel your home — while termites can demolish it. What to do? Begin here: Carpenter ants. Termites.

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