In the past few weeks, you may have noticed what looks like giant bees buzzing around. These giant bees are called carpenter bees and while not aggressive or harmful to humans they can do quite a bit of damage to any areas of exposed wood on your home such as deck or balcony railings, soffits, and window or door frames.
Carpenter bees appear in April and usually disappear by the end of May or early June. During that short amount of time, the female will look for wood in which she drills a perfectly round hole about ½ inch in diameter and deposits her eggs. Although the hole may look fairly shallow, the bee usually creates a tunnel for several inches. Once the female deposits her eggs, she collects pollen and deposits it into the hole to feed the newly hatched eggs.
Carpenter bees are very territorial and will return to the same spot every year. If left untreated for several years, the number of carpenter bees that return each spring will continue to increase as new eggs hatch out and return to the same spot.
Carpenter bees will attack any kind of unpainted wood. So the only real way to keep carpenter bees away is to regularly paint any bare wood surface or cover wood surfaces with vinyl. Even stained or preserved woods won't keep them away. Apart from painting, you can install a bee house where they can nest.
Carpenter bees don't like citrus oil. So you can boil citrus peels, let them cool, and then use a strain to pour the water into a spray bottle. Spray the solution on the nest until the bees leave and then seal the hole. As adults emerge in the spring, fill any holes with caulk, dowels, foam insulation, or steel wool.
Many people think that by plugging up the holes, the carpenter bee will die without an escape route, but in reality, they will just create a new place to drill out of. When treating carpenter bees, first of all, be patient. We tell our clients you really can't stop them from drilling, but when the season is over around the end of May to the beginning of June, we can come out and treat the holes.
Each hole must be individually treated with insecticide dust labeled for carpenter bee use. This odorless dust is puffed into each hole and will kill the eggs and adults that are in the hole. It will also kill any that visit the holes after treatment. This will greatly reduce the population of carpenter bees next season. Once the holes have been treated, customers can use wood putty to patch up the holes and repaint if so desired. Better yet, if possible, cover the exposed wood areas with easy to care for vinyl or metal.