Problems & Solutions, July 2000

Answers To Your Toughest Pest Questions

Q. A customer claims to have problems with powder post beetles but I am not sure they are still active. There are exit holes and some powder but I’m just not confident with this ID. I have enclosed beetles found on the windowsill and also pictures of the damaged areas. What do you think? (H.S., Va.)

A. The problem you described is not the first time a PCO has had problems with determining powder post beetle activity. This is the right time of the year for emergence, but you’re right — something does look a little off.

First, the beetles sent were not powder post beetles. They were dermestids — carpet beetles — and it is not uncommon to find dead dermestid beetles on window-sills. Next, the picture of the damage does have the round exit hole similar to anobiid powder post beetles. But I also noticed two other items of interest.

First, this appears to be an old structure, judging from the dimension and appearance of the wood (rough cut, larger dimension timbers). There also appears to be some etching on the surface of the wood. I would not be surprised if some of these exit holes were from bark beetles because the etching is similar to the working of a bark beetle. This would mean that this evidence is old and was in the wood when the wood was incorporated into the house.

Next, there may be some exit holes from anobiid beetles. Check the frass and see if it is discolored dark and clumpy, usually indicating old damage. Next, select a few areas in question and spray paint them with black paint or place masking or other tape over areas of suspected activity. If beetles are emerging they will come out and leave visible holes either in the spray-painted area or through the tape. If they are active the holes will appear quickly. Check back in about a week.

Q. I have a customer who is having a problem with Indian meal moths. I know they are Indian meal moths because I identified them and the ID was confirmed by an entomologist. But they seem to be all over the house! I suspect that there is some infested food but why would they be all over the house? (K.K., Mich.)

A. Yes, they are Indian meal moths and they can be all over the house. We tend to think of these moths typically infesting food but there may be other sources. One of the most commonly infested materials is birdseed. No on ever checks the dates on birdseed bags and I personally have opened bags to have moths emerge as I opened the bag. (In my discussion with the PCO he mentioned that the customer did have an outdoor bird feeder.)

Indian meal moths can be attracted to many other materials — even decorative planters or artificial flower arrangements. But I would concentrate on finding the sources of the infestation through inspection and the use of pheromone traps. There are several good pheromone lures for these moths and they attract moths in a fairly short time. Check with the customer to see if they have any window feeders, in addition to the outdoor feeder. They may keep a stash of birdseed in other rooms.

Once the areas of infestation can be established, removing infested food or objects will reduce the numbers. But don’t forget that the larvae of these moths move out of the food source to pupate, so look along ceilings and walls for pupated larvae. Check other materials stored around birdseed to find pupae. Be thorough. In some cases, an application of crack and crevice residual or dust will be a good deterrent against continuous wanderings of the larvae.

Q.We have a customer who has a continuing termite problem. We have treated two times and he has reported another swarm this year in a similar place in his first floor (slab) bathroom. He also inquired and insisted we place a baiting system around his house. We’d appreciate any ideas to see what we missed. (S.M., Pa.)

A. Today’s customer has the best of all possible worlds: a new termiticide and a new baiting system! I visited this house personally and noticed a couple of things during my inspection. First, the customer thinks the baiting systems will solve his problem immediately even though he likes to relandscape and remove stations. Next, during conversations with him, he said the swarm "behaved differently" this time than it did in previous years. He reported that the termites died and did not fly to the window as they have done before. Most likely they are coming into contact with a non-repellent termiticide used while swarming.

The decision to foam into the area under the shower area in the bathroom will probably resolve this swarming problem, but I feel the customer is skeptical. Since this house has already been treated twice, I discussed with him, as the PCO had, the probabilities of extended time before termites find the monitoring stations. Also, the PCO and I reminded the homeowner that he should not disturb the stations. Let’s hope there will be a hit this year in the stations and baiting will commence.