Problems & Solutions, May 2000

Answers To Your Toughest Pest Questions

IS EVERY BUG A PROBLEM?

Q. I found an insect that I’m unable to identify on the windowsills of a customer’s home. They were outside but they are not something I regularly see. They look like flying ants but are lighter in color then any I have seen before. Do you have any suggestions? (V.R., Orlando, Fla.)

A. After inspecting the property, I identified the insects as lace wing insects. These are rather delicate insects with a relatively short life cycle. Some species are very light in color, appearing almost pale green while others may have a golden color. They are predatory insects — their larvae are voracious feeders on many plant pests. They were probably attracted to the light at night.

These insects are not an infestation problem, but instead are a suggestion that something else is going on around the perimeter of the structure. The lace wing is sold like the lady bug (beetle) to organic gardeners and others for biological control. The populations may be high around this structure because of plant pests. If this is true then you should be looking for insects — like aphids — whose production of honeydew can attract ants.

Control is not necessary but controlling the plant pests will lower populations of this insect. In addition you may start to see more spiders around the structure, especially web builders, around lighted areas.

Q. We are having a problem with case-making moths. We have not had problems in this customer’s house before and we are finding them in different locations. Can you tell us why we’re finding them and what we should do? (M.C., Orlando, Fla.)

A. There have been increased reports recently of both the clothes moth and the case-making moth in structures. The reason may be that the materials these insects infest (natural fibers, like wool) are no longer treated with pesticides.

Where the case-making moth is coming from is sometimes difficult to figure out because they carry their "case" cocoon with them and when they are ready to pupate they move way from the material being fed on. However, they do not move that far away. In discussing this problem with the PCO later he mentioned that the customer had brought some stored items into the home. This often is the source of infestations. Remember that these moths can feed on many natural fibers like wool, but also the jute backing of carpets — the PCO mentioned that there are many oriental carpets in this house. Look under the carpets and inspect these carpets closely for damage.

To control these pests PCOs can use residual crack and crevice materials in closets and around baseboards. Check with the customer on what items were brought from storage and look for evidences of damage. As for the carpets, do not spray these as they can have dyes in them that would be affected by the pesticide. These carpets are handmade and use dyes different then those used in the United States. You could used a light dusting of an insecticide like boric acid, Drione, silica or Ficam D under the edge of the carpet, if you find damage or evidence in these areas. As for the cases (and moth pupae inside of them), vacuum them off of the walls and in the closets.

ODOROUS HOUSE ANTS
Q. We have been having trouble with ants around a structure and the populations seem to be growing. We have tried baiting and spraying but that only gives temporary relief. What can we do to keep these populations down or eliminate the problem? Also, the customers think the ants are damaging their azaleas. What is this other pest we’ve found on the bushes and what can we do for the customer? (C.C., Salisbury, Md.)

A. The ant the PCO sent me was an odorous ant. These ants can become a real nuisance and are difficult to control because of the size of the colony. The ant is also known for developing super colonies with many related group and many queens. The baiting of this ant (and others like these) offer a real challenge to PCO. You have to place baits close to the colonies — usually identified by the small mounds they make similar to pavement ants. But they can also nest between siding, etc., so a good inspection is as always the first step. Sugar baits should work well but many PCOs have had success with just about any bait. This will reduce the numbers but elimination may be difficult.

The other samples are lace bugs. They are plant feeders. The speckling of the leaves on the azalea is typical, as is the black "spotting" on the underside of the leaves. The insect itself is very small. The wings have a lacy appearance (thus their name). The two problems are unrelated but these plant feeders can also attract ants because they produce honeydew for ants to feed on.