Controlling Silverfish and Firebrats

W.L. Gojmerac and P.J. Pellitteri

Silverfish and firebrats are common household pests. They eat foods and materials that are high in protein, sugar, or starch--such as cereals, flour, fabrics, starch in clothing, and paste or glue on wallpaper and bookbindings.

What they look like

Silverfish and firebrats look somewhat alike. Both are slender, wingless and covered with scales. Adults are 1/3 to 1/2 inch long. Silverfish are shiny or pearly gray; firebrats are mottled gray. Both have two long feelers and three body-length tail-like appendages.

Silverfish and firebrats dislike light and are active at night. They run with a characteristic darting movement and you will seldom see them during the day unless their hiding place is disturbed and they dart out to seek another.

Where they live

Silverfish live in damp, cool places such as basements. Large numbers are sometimes found in new buildings where walls are still damp.

Firebrats prefer hot, dark areas around furnaces and fireplaces, and insulation around hot water or heating pipes. To find food, these insects do considerable traveling throughout the house, often along walls, baseboards, pipelines, and heating ducts.

Firebrats also are commonly found in bookcases and closets, and behind baseboards and window frames.

Control

Insecticides designed for home use usually control a number of insect pests. However, you still need to carefully select the product most suited to your pest problem. For example, some insecticide products are designed to kill flying insects. They are quick-acting and deposit no toxic residue, so they will kill only those pests contacted with the insecticide. Since silverfish and
firebrats hide during the day, applying a nonresidual spray would kill only those pests contacted by the insecticide. For this reason, product selection is important.

In addition, manufacturers sometimes combine two or more insecticides (active ingredients) into one product. If the product label says it will control silverfish and/or firebrats, and if you apply it properly to the right places, it should effectively control these insect pests.

Sprays

You can effectively control silverfish and firebrats with commercial sprays containing chlorpyrifos (Dursban), diazinon (Spectracide), malathion, permethrin, or propoxur (Baygon).

You can purchase ready-to-use sprays containing one of these chemicals in most nursery and garden supply centers and in many supermarkets and hardware stores. Aerosols also are available. Follow label directions exactly, and always check the active ingredients listed on the label to make sure the spray contains one of the aforementioned chemicals and can be used indoors.

Thoroughly spray surfaces that silverfish or firebrats crawl over. Spray around baseboards, door and window casings, closets, and places where pipes go through walls or floors.

Before spraying around upholstered furniture, draperies, carpeting, or wall coverings, test an inconspicuous spot to make sure the chemical will not stain the fabric. If you are doubtful about treating some surfaces, consider calling a professional pest control operator who will assume the risk and liability of the treatment.

Remember, sprays do not always take effect immediately. However, when properly applied, they leave a residue that controls the insects within a few weeks.

Dusts

Insecticide dusts containing any one of the previously mentioned insecticides also will control silverfish and firebrats. While dusts leave a visible residue that you may find objectionable, they may be more effective than sprays because they can be blown into cracks behind furniture and in other places hard to reach with a spray.

Silverfish and firebrats are highly mobile, so apply the insecticide (preferably on the same day) to all areas in your apartment or home that might serve as breeding or hiding places. This prevents them from going from one room to another. Follow label directions exactly.

Use insecticides safely

1. Check label directions and safety recommendations every time you use insecticides.
2. Keep insecticides in original, labeled containers away from children and animals.
3. Store insecticides where they can't be mistaken for food or cleaning products.
4. Put away or carefully cover all foods, dishes, and utensils before spraying.
5. Keep people and animals away from treated areas.
6. Avoid unnecessary exposure when using insecticides.
7. Don't smoke, eat or drink when you are working with insecticides.
8. Wash hands and face thoroughly with soap and water after using insecticides.
9. Throw empty containers in the trash. Do not leave them where
   children or animals can get them.
10. If poisoning occurs, seek medical care immediately. Save the insecticide label to show your doctor.