firebrat image


Photo by Clemson University - USDA Cooperative Extension Slide Series


Photo by Edward L.Manigault

Photos used with permission, courtesy of


Silverfish and firebrats are amongst the most primitive of all insects. While many insects have a four stage life cycle (complete metamorphosis), these undergo a three stage life cycle called gradual metamorphosis. Once they hatch from the egg form, all stages appear similar in appearance, except for size.

Silverfish and firebrats can be found almost anywhere, but their preference is for warm, moist locations. Some favorite spots include furnace/boiler rooms and bathrooms as well as any other damp, warm area. Firebrats may be found outdoors as well. Silverfish are frequently introduced with newly installed dry wall as they are able to chew on the paper backing. They also feed on a variety of food products including dried food, starches, paper (such as books), glues, pastes, linen and even non-organic fibers. Silverfish may survive without food for a long periods of time which makes control more difficult.

Though both silverfish and firebrats seek heat, silverfish prefer more moderate temperatures between 70 and 80 degrees F whereas firebrats may be found in areas where temperature are more than 10 degrees higher such as near ovens or in steam tunnels. One may also find these insects in attics.

Where To Find Them

A new area to check for silverfish has recently come to our attention: wood mulch ground covers outdoors. Theoretically, these insects could be delivered with mulch and breed within the mulch where heat and moisture are generated by the natural composting process.

One observant homeowner, a visitor to this web page, was finding many silverfish despite insecticide treatments inside her home. Then, one evening, she observed silverfish outside her home near one of the windows. Theorizing that the mulch may be a source of the problem, the mulch was removed. The homeowner has reported that following the removal of the mulch, the problem is much improved.

Another visitor to our site suggested that instead of totally removing wood mulch, it is possible to move it out of the area, install a 12" barrier of lava type rock or similar drainage material and then move the mulch back into place.

Since learning of a possible relationship between mulch and silverfish, we have had written confirmation from Dr. Austin Frishman, a well known Pest Management consultant, indicating that mulch may indeed be a conducive factor where a silverfish problem exists.

Pest Management

Control of these pests involves removal of their food source where possible. After that, insecticide treatment in common hiding areas such as in cracks, beneath plumbing fixtures, in basement or attics areas or any place that a problem is noted. The most effective way to treat for these pests is to apply a residual insecticide liquid such as Permacide P-1 as a pin (jet) stream to the areas mentioned above as well as all corners of all the rooms including those going from the floor to ceiling as well the area where the wall meets the ceiling. In addition, treat around window frames, door frames, baseboards moldings or any other possible harborage areas. Outside, consider applying the spray around window frames, door frames and along the foundation area where silverfish may enter. To treat in attics, use of a total release fogger such as Pro Control Plus which may help to eliminate exposed stages of silverfish or firebrats there.

Because control of these insects is sometimes difficult, we recommend that two to three treatments be made at 30 day intervals. It is important to repeat the application at least one time after the initial application.

We also offer Drione Dust as an option. Drione Dust may be applied to cracks and crevices, wall voids or behind areas where silverfish are a problem. Silverfish are not likely to return to treated areas.

Finally, we offer two granular baits that control silverfish. One product that we offer is a bait product called Niban FG (long "i" as in eye). Niban FG Fine Granule Insect Bait comes packaged in a convenient 1 lb applicator pouch with a flip top. This product is a finely ground food bait treated with boric acid. The other bait product that will control silverfish is Maxforce Complete. This product is also weather resistant and contain the Hydramethylnon as the active ingredient.

The product has no odor other than that of the food attractant and in small amounts, it is virtually undetectable. This is a great product for sensitive situations where pets such as birds are present. It is also suggested for homes where chemically sensitive people live because it has no "pesticide" odor. The product may be applied into cracks or crevices, behind items or in attic or basements as needed. Since this product is weatherized, it may be applied outdoors as well in case silverfish are entering from around the foundation.

Niban FG can also be used for ants, crickets and cockroaches inside or outside.

Please visit our products page by clicking here for information on products that we sell. The products to look at would be Drione Dust, Pro Control Plus Insect Fogger, Niban FG, Maxforce Complete and Permacide P-1.

Contact Us

We hope that this information will be helpful to understanding these insects. We offer additional information by making a simple telephone call, by faxing to us or sending us E-mail.Call us at 800-433-1128 or 845-356-2837 weekdays between 8 am and 4 pm ET, send a fax to us at 845-746-9018 or send E-mail to

We try to respond as quickly as possible to any inquiries we receive. We value our relationship with you.