Pest Briefs: Silverfish 101 (Bristletails: Silverfish and Firebrats)
By: Robert (Bob) Batman

NATURAL ENTOMOLOGICAL CLASSIFICATION Phylum Arthropoda Class Hexapoda or Insecta Order Thysanura Family Lepismatidae Genus/species Various Without metamorphosis (change in form): newly hatched are the same shape (form) as adults, just smaller.

MORE THAN ONE SPECIES: Bristletails existed over 400 million years ago! Now that's adaptability. Most customers don't know the differences between silverfish and firebrats, but a PCO should! Pest control operators are usually concerned with only the following four genera and species: 1) Lepisma saccharina (Linnaeus), the common silverfish, 2) Ctenolepisma longicaudata (Escherich), the gray silverfish, 3) Ctenolepisma lineata (Fabricius), the four-lined silverfish, and 4) Thermobia domestica (Packard), the common firebrat.

A FEW FACTS ABOUT EACH: 1) The common silverfish prefers temperatures between 70 and 80 degrees F and dies when temperatures remain above 95 degrees F. for a period of time. Don't look for these in your attic in the summer. 2) The gray silverfish prefers California and New England. 3) Of the above species, only the four-lined silverfish is commonly found indoors and outdoors in our part of the country: check out your mulch and/or gravel beds and wood shingle siding and roofing! This silverfish isn't picky regarding whether it is dry or moist: they can tolerate both environments just fine! 4) Firebrats prefer temperatures in access of 90 degrees F and like the wood shingle roofing materials. Silverfish cannot tolerate the hot attic temperatures during warm weather months, but the firebrats love it! No self-respecting firebrat would be caught dead inside an air-conditioned house (temp: 69-80) when he/she can be in the hot attic! Rule of thumb, silverfish prefer temperatures below 90 degrees F while firebrats prefer temperatures above 90 degrees F. Both silverfish and firebrats have a life span of several years.

ITS TIME TO EAT! WHERE'S THE FOOD? These animals feed on a variety of things which include either proteins of carbohydrates, or both, including but not limited to 1) Starches, glues, gums, casein, and dextrin (binders found in cloth and adhesives), 2) paper which has had sizing, paste, or glue application (book bindings, labeling materials, wallpaper, cellophane, art cloth, and boxes), 3) wheat flours and starches and products made from same, 4) fabrics (starched clothing, rayon, linen, artificial silk, and cotton), 5) dried beef and beef extracts used in adhesive products, and 6) some are cannibalistic.

WHO NEEDS FOOD? These animals can withstand very long periods without food or water: Lindsay (1940) observed one adult survive 307 days without food. She also noted 1) that Ctenolepisma longicaudata (Escherich) had a cellulose-digesting bacteria and fungus hyphae in it's crop and, 2) it, C. Longicaudata (Esch.), does not actually drink liquids: it gets its moisture from the moisture content of its food.

HOME SWEET HOME, WHERE'S HOME? Silverfish and firebrats generally live and breed in the inaccessible parts of a building (within walls, within the voids between floor levels, within the cracks and crevices of wood shingling, under carpeting, and under and behind insulation). Most building infestations include more than one species of silverfish and, of course, firebrats. They are initially brought into buildings in constructions materials, boxes containing various items, or gain access from landscaping materials which are placed adjacent buildings.

TRUE STORY NUMBER 1: A longtime commercial account (a restaurant) which was presently undergoing remodeling phoned our office for a special service: "We have miniature, prehistoric-looking monsters all over the restrooms! Help!" To make an otherwise longer story short, they had common silverfish, Lepisma saccharina (Linnaeus), infesting all the boxes of ceramic tile. Boxes of tile had been delivered and placed in each of the restrooms during remodeling of same. Our service technician performed appropriate service and the problem was resolved before it could spread.

TRUE STORY NUMBER 2: A residential customer was building a new house and had prearranged for certain pest control measures to be performed during construction. One of the control measures was a thorough pesticide application to the attic areas prior to placement of insulation and another immediately following placement of insulation. In mid summer, our service technician treated the attic areas with liquid residual pesticide followed by fogging, as scheduled, five (5) days before the insulation crew arrived. No silverfish were observed at the time of the first attic service by our technician or the customer (who was present). The customer had scheduled for the attic to be treated (liquid residual followed by fogging) three (3) days after the insulation crew finished their work. When the service technician performed the second attic treatment, as scheduled, he and the customer (who was present) claim silverfish and firebrats were falling from the rafters and number one cedar shingles like rain drops! The customer said he couldn't believe what he was seeing, and to never tell his wife about it. The insulation material was obviously infested with silverfish and firebrats before it was brought to the construction sight!

"HOLY SILVERFISH BATMAN!" A customer will sometimes hold up an article of clothing and say, "look what the silverfish did!" The customer points to a hole in the garment you could drive an Ohio class submarine through and wants the attic treated, again! There are several critters that can make such holes in clothing, but none of them are silverfish or firebrats!

SILVERFISH AND FIREBRAT PROBLEMS REQUIRE APPROPRIATE TREATMENT: In our area of the country, contractors build a variety of houses: some are built on slabs, some over crawl spaces, some have basements, some have a combination of the afore- listed, some have partly inaccessible crawl and/or attic areas, and some have crawl areas and/or attic areas which are totally inaccessible! Various types of insulation and roofing material is used, sometimes on the same house. A wide variety of landscaping material is available, and used. We have old houses (many over a hundred years old), many not so old, and thousands of newer and new homes. The same can be said for commercial construction: lots of variety!

Serious problems require serious solutions. Silverfish and firebrat problems need to be addressed at an adequate level (extent of service) and frequency to successfully combat the existing situation(s). Some situations may need a regularly scheduled service (monthly, every other month, or quarterly) following the initial service, and some situations may require less service. A professional pest control service technician is trained to give recommendations based on existing situation(s). As with any pest, the pest situation can change, and sometimes additional control measures are needed. The customer must be willing to authorize the extent and frequency of service needed, when needed, otherwise the problem may magnify. Silverfish and firebrat problems are usually good candidates for a monthly or quarterly service program.

WHAT HOMEOWNERS NEED TO UNDERSTAND ABOUT A QUARTERLY SERVICE PROGRAM: A quarterly service program is not a clean-out all the pest problems type of service. It (a quarterly service program) is designed to provide an economical approach (low cost service) which aids in the control of certain pests, but such a program is not a cure-all and cannot prevent certain problems from arising between visits. First of all, a quarterly service program is a low cost, minimum service program. Secondly, all houses have obstructions and conditions which prevent placement of pesticides and/or utilization of other control methods where the pests live and breed. A service technician's effort is limited: 1) as to where pesticides can be placed and/or, 2) where other control measures can be performed and, as a result of such limitations as well as other factors, pest situations change, and sometimes additional service (service in addition to the regular quarterly service) is needed. A customer who is reluctant to authorize what is recommended or needed, when it is recommended or needed, may suffer the consequences. This is never more true than when discussing attic treatments for silverfish and firebrats. There are different types of attic treatments: some are inexpensive and some are not. Some situations need the more expensive treatments: some do not. Depending on the attic situation, it can be fogged, dusted, baited, treated with liquid residual, or a combination of the afore-listed. There are various fogging agents, dusting agents, baits, and liquid residuals: some are inexpensive and some are not. The options line up like a restaurant menu: each listed along with its price. Which one do you need?

Example: you phone a PCO for service and you tell the PCO you have 2,000 square feet of living space plus a full basement, a two car garage, and a10,000 cubic foot attic. You tell the PCO you have a silverfish problem and want your house and attic treated. The PCO explains and prices the service as follows: X number of dollars plus any appropriate tax (some states have a service tax) to treat the accessible areas of the house (living quarters, basement and garage) plus an additional amount for the attic treatment. The PCO explains the price options for attic treatment ranging from $10.00 per attic entry to $120.00 per attic entry, plus any tax. Which level of service does your attic need? Which level of service do you think is going to give the best results?

When the service technician arrives at your house to perform the requested service, he/she may recommend either a more extensive or a less extensive attic service than the one you have requested. Some technicians, when they believe a situation justifies it, make an on-the- spot recommendation based on their experience: nothing wrong with that. It's just a recommendation regarding the level of service needed from an experienced professional, you don't have to take his/her advise. The technician should cheerfully perform whatever extent of service you are willing to pay for. But, remember the old saying, you get what you pay for.

Tired of Silverfish?
If you live the Greater Kansas City Metro area, give Best a call: (816) 765-8844 or (913) 671-8844.