Case Studies

Cowleys Pest Services Case Studies: Carpenter Bees damage storage shed - Bee removal and control in Bayville, NJ

Wednesday, July 13th, 2016 by Brian Ordonez


I was called out to a home in Bayville after a homeowner had contacted Cowleys Pest Services. She reported seeing large bees flying around her backyard. Upon arrival, I spoke with the customer. She did not know where the bees could be nesting because she was avoiding entering her backyard as long as there was an active infestation. However, she was positive that she saw bees and not wasps.

It was time to conduct my inspection so that I could determine the type of insect I was dealing with and the location and level of the infestation. It did not take me long to discover that this homeowner had a carpenter bee infestation. When you see large shiny black bees hovering around perfectly bored holes, it is a virtual certainty wood-boring carpenter bees are nesting in the wooden part of some structure. Usually, the wood that carpenter bees are attracted to is soft or rotting. These bees look for unpainted and unfinished wood has been exposed to the outdoor elements and is often in need of repair. 


Carpenter bees are common household pests. For those not that familiar with insects they can easily be confused with bumblebees. Both have thick bodies, emit a similar sound when buzzing around, and are about the same size. However, it’s pretty easy to tell them apart. First, their coloration is different. Bumblebees are hairy, black and yellow. Carpenter bees are shiny black. Another difference is their behavior. Bumblebees, which are a welcome sight because they are important for pollinating plants and flowers, do not cause any property damage and they are not overly aggressive. Bumblebees rarely sting unless touched or their nest is threatened or disturbed. While carpenter bees also pollinate, they do cause property damage when the female bores into wood to lay her eggs. By doing so, she produces holes that look as though they have been drilled with the precision of a 1/2 inch drill bit.  Carpenter bees also fly much faster than bumblebees, and the males are very territorial. They’ll fly erratically around people if they are “trespassing” too close to their nests. Although the male carpenter bee does not sting, its large size and aggressive behavior can be intimidating, especially for children.

With this property in Bayville, I found two separate areas where carpenter bees were nesting. The first was along the eaves of her storage shed and the second was in the wood railing of her deck. As shown in the photos, I observed wood shavings and pollen on the deck caused by the carpenter bees burrowing into the railing. 

The usual and most obvious sign that you have a carpenter bee infestation is sawdust (fine wood shavings), also known as sass. This debris piles up below the holes where the bees have been boring into the wood. As with many insects, the female is the one who builds the nest by burrowing into the wood to lay her eggs. The male hovers nearby to protect the queen from any predators or other male bees. If a carpenter bee infestation is not treated, these bees are as persistent as they are invasive. Inevitably, they stay year after year in the same location because the female overwinters in the gallery. While not as destructive as termites, carpenter bees are capable of causing significant damage.



I  treated the gallery holes (burrows) by applying a residual insecticide dust individually to each one. This method, while time-consuming, is highly effective for eliminating the female from the gallery. Once the female is dead and gone, there will be no more drilling. Even though the male does not bore into the wood, he goes into the gallery at night when temperatures drop, so he is exposed to the dust as well. Finally, the dust has a long residual effect, so it will kill the larvae when they mature. After, I used a foam treatment to seal the holes.

After applying the treatments, the carpenter bee activity came to a virtual standstill. The homeowner was pleased that she could once again enjoy her backyard.