Pest Facts: Silverfish
Probably the most commonly encountered bristletail is the silverfish, Lepisma saccharina Linnaeus. The silvery scales of the silverfish rub off easily when touched or moved. The scales can lead to a “dirty” or “smeared” appearance on walls or on paper. Other species of silverfish include the Gray Silverfish, Ctenolepisma longicaudata Escherich, found from the Midwest to the West Coast, and the Fourlined Silverfish Ctenolepisma lineata (Fabricius), found in the eastern and western parts of the US but relatively absent in the Midwest.
- Color: Not always shiny silver; color can vary from silver to dark gray.
- Legs: 12-19 mm
- Shape: Oval
- Size: 1/2 -3/4 inch
- Antennae: Yes
- Flying: No
- Region: The eastern and western parts of the US but relatively absent in the Midwest.
Silverfish typically prefer warm areas of 70 plus degrees Fahrenheit but typically prefer temperatures not to exceed 90 degrees Fahrenheit. They also prefer moist or humid areas. These conditions are ideal for optimum survival and egg laying and development.
Silverfish usually infest structures such as houses and other dwellings, commercial buildings, schools, libraries, and any other structure with conditions conducive to survival and with adequate food sources. Silverfish prefer to stay hidden in tight places and are mostly activate at night.
Prevention & Treats
Thorough inspection is required to find the source and the areas infested. Reducing humidity frequently helps. Granular treatment using baits can work well in attics and areas that are relatively inaccessible. Crack and crevice applications of various products labeled for the site area are also common. Always make sure that the site is on the label. With the new granular baits on the market, broadcast applications of fine dusts are no longer the norm. If dusts are used, it is wise to make sure that the dusts are applied beneath any insulation and inaccessible to the homeowner. After modifying the environment, reducing food sources, and applying any product of choice, followup inspections should be scheduled in accordance with label recommendations.
*Resource credit: Courtesy of the National Pest Management Association*