Thom Smith | NatureWatch: How do I safely get rid of carpenter bees?

Posted
Don't miss the big stories. Like us on Facebook.  

Q: There may be carpenter bees again damaging our home. We sprayed them last season and before, but with little success. Any idea you can give will be appreciated. We don't like to spray bees in general because they are so important to our environment by pollinating flowers for vegetables, fruits and beauty in the garden. But what to do?

— Michael, Pittsfield

A: It is true, they do damage wood and, in some cases, over time, weaken timbers, joists and beams. On the other hand, like many other bees they do pollinate. This probably provides little salvation for the insects if they are damaging your home. While I have mentioned in the past that they are not aggressive, I was referring to the males that remain on guard and will buzz around anyone encroaching on "their territory"; they have no stinger and, thus, are harmless. Female carpenter bees can sting, but are docile and very rarely sting unless caught in the hand or stepped on barefooted.

Carpenter bees (of which there are some 500 species worldwide) make nests by tunneling into wood, preferably unpainted. The entrance is a perfectly circular hole a tad over 1/2 inch (16 mm). They do not eat wood and discard the bits or sometimes reuse them for building partitions within cells or tunnels. The tunnel, or more often side tunnels, may be used as a nursery for the brood and storage for pollen, which feeds the developing insects. If you see a woodpecker excavating holes adjacent to the tunnels, or on wood facing on your house, shed, etc., they have been attracted by noise made by the bee larvae. There are a couple kinds of flies that lay their eggs at the entrance to the bees' nest and their maggots live from eating the helpless bee larvae.

I hate mentioning poison and bees in the same paragraph. Blocking or poisoning nests are sometimes ineffective because the previous year's bees will return to the nests they came from and, if plugged or poisoned, the bees will start a new hole. The most effective means of destroying the nest and its inhabitants is to apply an insecticidal dust directly into the opening. This is best accomplished by carefully reading all instructions and cautions and using a duster that will puff the dust up into the tunnel and coat the sides. And, of course, wear a protective mask, goggles and gloves. To be on the safe side, do this at night, if doing so is not in itself dangerous. If you must treat during the daylight hours, use a pyrethrum spray or a dangerous wasp and hornet spray to knock down any bees flying about. Or better still, apply the powder and forget the sprays, hoping not to be stung. It is advisable to wear protective clothing and other protection mentioned above.

Best, you can block the holes with steel wool and later apply waterproof caulk to patch the area. Keep all wooden surfaces well painted.

Q: We have many shrubs along the edge of our yard and for several years we have had small sparrows and robins nesting in them. One year, we also had a mourning dove pair nest in one. Our yard is large and the shrubs are scattered. We also have some large evergreens, I think pine. Never have we seen both abandoned nests that had little birds in them, and a couple of crows that may have been nesting in one of the evergreens. Could this be a coincidence? I read in your column not too long ago that you blame crows for disturbing or killing rooftop nesters. Could this pair of crows be killing the nesting birds, namely the robins' offspring?

Article Continues After Advertisement

— Charles, North Adams

A: Being the opportunist that crows are, it has made a lot of enemies, some justified, others not. Studies have been done on the damage crows do to what we might call desirable wildlife, and removing them has made little, if any, change in the number of eggs or baby birds destroyed. Remove the crow and another predator is apt to take its place. Young robins and eggs are preyed upon by snakes, squirrels, common grackles, blue jays, in addition to crows and ravens. As for baby robins being taken by a crow, it should be known that most baby robins die (crow or no crow) before adulthood. And the American robin population has increased nearly identically to the crow population. The Cornell Laboratory of Ornithology states on its "All About Birds" website, "On average, though, only 40 percent of nests successfully produce young. Only 25 percent of those fledged young survive to November. From that point on, about half of the robins alive in any year will make it to the next." It is almost as if the American robin is dispensable, and probably only survives in good numbers because of raising three broods a summer with three to five eggs at each nesting.

Crows are not "all bad," they do help the farmer by eating a quantity of insects that attack their crops. True, they also have a liking for corn and seedlings. They are omnivorous, eating almost anything from seeds, fruits and nuts to insects, mollusks, eggs and nestlings. They also feed on carrion and at garbage dumps. Crows are also known to take cat and dog food from outside bowls. And finally, crows are smart birds, known to use tools to a limited extent. Crows in our neighborhood carry dried bread tossed out by a neighbor to our bird bath for softening — or at least did when we had a bird bath. It is native, migratory (although not long-distance), and a songbird (although not able to sing very well according to our standards), hence it falls under the requirements for protection, although it does have a hunting season.

Article Continues After These Ads

READER OBSERVATIONS

June 23, 1:52 a.m.

I heard some different noises on the front porch about 1 a.m., and I looked out in time to see a rather large individual eating my sunflower seeds. He must have been cold as he was wearing a fur coat. I was not able to invite him in because he had already had a snack and I thought the hour was too late for polite conversation. I need to find my whistle so that if he comes again, I can greet him more properly. The early settlers on Williams Street had [Native Americans] for guests, but we have to settle for the Ursine species.

— Norma via Patricia

Article Continues After Advertisement

June 28, 7:35 p.m.

Two coal black squirrels together near Pecks and Old Ore Bed roads.

— George

June 29, 9:05 a.m.

While checking the garden after 2 inches (so says the rain gauge), I found a beat-up and dead butterfly with one wing missing. I don't know what it was, but it was yellow and black. I believe it was the storm yesterday afternoon.

— Ken, Pittsfield


TALK TO US

If you'd like to leave a comment (or a tip or a question) about this story with the editors, please email us. We also welcome letters to the editor for publication; you can do that by filling out our letters form and submitting it to the newsroom.




Powered by Creative Circle Media Solutions