Carpenter Bees

Learn more about carpenter bees so you are better equipped to deal with these insects if they decide to invade your home or property.

Biology of Carpenter Bees
Carpenter bees are yellow and black bees which are large in size. They typically appear during the spring where they spend time under a porch or deck rail or a home’s eaves. It is common for people to mistake carpenter bees for bumble bees, but you can identify carpenter bees by their tail section which is black and shiny. These bees have very strong jaws that they use to create holes in wood, helping them earn the title of pests. They do not eat the wood for food, however. Instead, they solely excavate it to create tunnels for their nesting sites.

Carpenter bees will typically spend the winter in their old nest tunnels. When April or May arrive, the males will appear, followed by the females. You can spot the male carpenter bees thanks to the whiteish spot that appears on their front by the face. Males also do not have any stingers. They are, however, territorial. Female carpenter bees might sting, but they do not so often. They are only likely to sting if they are highly agitated, such as when being held in your hand. Carpenter bees do not create colonies, instead preferring solitary lives. A mated female will feed on plant nectar then start making new tunnels. These galleries can be over a foot deep but are usually between six and seven inches. Some bees might share an entrance hole but with separate interior galleries. When mated females create their tunnels, they collect pollen and mix it with nectar, which will be food for the baby carpenter bee. She will then deposit one of her eggs by the pollen ball and create a seal on the tunnel’s section with some chewed woods. Female bees will fill the tunnel like this, typically making six or seven separate cells before dying in weeks. The eggs hatch after a few weeks and the offspring develop fully within five or seven weeks, emerging in late summer.

Why Carpenter Bees Are Considered Pests
One of the most annoying problems caused by carpenter bees is their time spent excavating tunnels within wood, something they are able to do thanks to their strong jaws. This leads to entrance holes that are about a half inch in diameter and typically along a board’s underside. The first sign of these holes is frequently some coarse sawdust underneath. You may also be able to spot some yellowish-brown stains by the wood next to the hole. This is from voided fecal matter. It is possible that woodpeckers will be attracted to the hole in search of larvae, causing even more damage. Additionally, the hole can allow water to get into the home, which leads to other problems.

Unfortunately, any wood on your home that is exposed is at risk of damage from carpenter bees. Even treating and painting the wood does not eliminate the risk, it just reduces it slightly. Even woods that most assume are pest-resistant, such as redwood, cypress, and cedar, are not when it comes to carpenter bees. Male carpenter bees will not sting as they do not have a stinger, but there is a small risk that females will sting people, especially if agitated.

Methods for Controlling Carpenter Bees
Unfortunately, it is nearly impossible to prevent damage from carpenter bees completely. That is because the protective sprays for insecticides that professionals can apply to wood will only work for a temporary period, even if you reapply them regularly. Furthermore, since the bees do not eat the wood, there is not even any guarantee that they will ingest or be exposed to the pesticide in lethal doses. Furthermore, the fact that any exposed wood is at risk means that any effort to control carpenter bees must target every single piece of exposed wood. It is simply impractical to apply pesticide to every area of the home.

Unfortunately, the best solution and the one most often suggested by professionals is to individually treat every entrance hole you find being used by carpenter bees. You can do this use an insecticide dust or spray, including products with resmethrin, cyfluthrin, or carbaryl. Of course, using these insecticides requires care as you do not want to inhale or come into contact with them. You will also want to seal the carpenter bee tunnels using small balls of aluminum foil. Then caulk them up after 24 to 36 hours. Sealing the tunnels ensures that abandoned tunnels do not get reused in the spring or used for winter nesting. You must both seal the tunnel and use insecticide. If you just seal it, some bees will just create new exit holes.

DIY Tips for How to Get Rid of Carpenter Bees
If you have a serious problem with carpenter bees in your area, a dramatic but effective DIY approach would be to change the siding on your home. Instead of using wood siding, opt for composite materials and similarly replace any porch rails and other exposed wood. Without exposed wood available for tunneling, carpenter bees will not be attracted to your home. Of course, this is a dramatic change and most homeowners will be hesitant to take that step without significant reason. There are also numerous do-it-yourself options that have varying success, but typically only produce short-term results. One option is to play some loud noises on speakers by the infested area since carpenter bees do not like noise. The thing to remember, however, is that the bees may return after you stop the music, so you will need to treat the holes immediately after they leave.

You can also try using natural remedies like a citrus spray instead of insecticides. This works based on the natural aversion of carpenter bees to citrus oil. Although it will not kill the insects, it will encourage them to leave. The same is true of almost oil. Before attempting to do any carpenter bee treatment yourself, always plan for the risk of being stung. Your attempts are more than enough to potentially agitate the females, causing them to sting.

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