Friday, February 10, 2012

What are the large, black bees hovering around my house?

 Although these insects look similar to bumble bees, they are actually Sonoran carpenter bees. The female is black, and rather large, approximately one inch in length. They can sting when angry but are considered shy and rarely bother humans. The male bees are golden brown in color and lack a stinger. They inhabit the Hawaiian Islands, the Marianas, China, Japan, New Guinea and the Philippines.

The females fly around homes seeking out nesting sites:  wooden roof shingles, exposed roof rafters, window sills, wooden fences, and picnic tables. They also  prefer dead softwoods such as redwood and pine, as well as dead parts of trees.

The females will burrow into the wood and create galleries to lay her eggs. Egg laying occurs year-round but may decline during the winter months.  A ball of pollen is placed in the tunnel as food, one egg is laid on the pollen and the chamber is sealed with wood shavings.
The first step in protecting the home is to paint exposed wood.  Painted wood has been reported to be far less susceptible to attack. In addition, entrance holes may be dusted with an approved insecticide.