Carpenter bees are large robust insects that look much like bumblebees. They have a bare shiny black abdomen whereas bumblebees have a hairy abdomen with yellow markings. Male carpenter bees, identified by the bright yellow spot in the middle of the head, are aggressive but quite harmless since they lack stingers. Females can sting if antagonized.
Carpenter bees bore 3/8” – 1/2” round holes in wood to create tunnels in which to raise their young. Soft wood such as California redwood, cedar, white pine, or poplar is preferred.
Adult carpenter bees emerge from overwintering sites in old nest tunnels to mate in the spring. The female prepares a nest by boring a new tunnel or more frequently by cleaning out and expanding an existing one. Tunnels run from several inches to ten feet in length. After the nest is ready, she places a mass of pollen mixed with nectar in the back of the tunnel, lays an egg on it, and builds a partition of chewed wood pulp to form a brood cell. Six to eight brood cells are constructed in each tunnel. Bee larvae develop on the pollen/nectar mix and emerge as adults 30 to 40 days later in the late summer.
WHAT TO DO:
- Infested wood can be replaced with treated lumber or wrapped with flashing.
- Several coats of paint or varnish discourage boring.
- Wood stains or sealants usually do not prevent tunneling.
We offer several options to eliminate carpenter bee problems:
- Deep injection treatment of individual nesting tunnels is necessary for initial control.
- Boring and tunneling can be deterred by periodic application of repellent insecticides to susceptible wood surfaces.
- Holes should be plugged in the fall to deter future nesting.
Year round protection is available through our Commercial Eco Guard, Eco Select or Eco Premium service plans which help protect you, your home or business and your family from unwanted problems as new pests tend to occur again in the same or similar locations due to the environmental conditions in and around your structure. Details are available from our service specialist or by calling our customer service center at (585) 993-9100.