Booklice and Silverfish1
Booklice
Booklice (Figure 1) belong to a group of insects collectively called psocids. The psocids are small, soft-bodied insects, most of which are less than one-eighth of an inch long. They are both winged and wingless. Psocids have chewing mouthparts.
Booklouse.
The majority of psocids are outdoor species with well developed wings. They are most commonly found on bark or on the foliage of trees and shrubs. These psocids are frequently called "barklice." Most of the species found in buildings are wingless. Because they are often found among books or papers, they are called booklice. The term "lice" in the names is somewhat misleading because none of these insects are parasites and few of them have a louselike appearance.
Psocids feed on molds, fungi, cereals, pollen, fragments of dead insects, or other similar materials. They cause little loss by actually eating foodstuffs since they do feed chiefly on mold. At times they may become extremely abundant and spread throughout an entire building. In such situations they may contaminate foods and materials to the point the goods must be discarded. Damage to books may be more direct. They eat the starch sizing in the bindings of books and along the edges of pages.
The eggs of psocids are laid singly or in clusters and are often covered with silken webs or debris. Most species pass through six nymphal stages. The entire life span from egg to adult is between thirty and sixty days.
Control
Reduction of moisture to eliminate formation of mold is a very effective method for controlling booklice. Infested furniture, bedding, or other movable furnishings should be thoroughly cleaned and aired. Clean up spilled food products and keep all stored products tightly sealed.
If an insecticide is required, apply a spot treatment or crack and crevice treatment of products found in Table 2, according to label directions.
Precautions
All insecticides are poisons. Read the entire label, including the small print before opening the containers and heed all warnings and cautions. Store pesticides in their original labeled containers out of reach of children, irresponsible people, and pets, and preferably keep under lock and key. Dispose of leftover spray materials and empty containers promptly and safely.
Silverfish and Firebrats
Silverfish (Figure 2) and firebrats may cause damage in the home by eating foods or other materials that are high in protein, sugar, or starch. They eat cereals, moist wheat flour, paper on which there is glue or paste, sizing in paper and bookbindings, starch in clothing, and rayon fabrics.
Silverfish.
Silverfish and firebrats are common in homes. The silverfish lives and develops in damp, cool places. Large numbers may be found in new buildings in which the newly plastered walls are still damp. The firebrat lives and develops in hot, dark places, such as around furnaces and fireplaces, and in insulations around hot water or steam pipes.
In apartment buildings the insects follow pipelines to rooms in search of food. They may be found in bookcases, around closet shelves, behind baseboards, windows or door frames.
Silverfish and firebrats are both slender, wingless insects and their bodies are covered with scales. Adults are about one-third to one-half inch long. Silverfish are shiny and silver or pearl-gray in color. Firebrats are mottled gray. The young insects look like adults except they are smaller.
Both insects have two long slender antennae attached to their heads and three long tail-like appendages at the hind end. Each appendage is almost as long as the body.
Silverfish and firebrats are active at night and hide during the day. When objects under which they hide are moved, they dart about seeking a new hiding place.
Biology
Under usual house conditions, silverfish and firebrats develop slowly and have few young. They are hardy and can live for several months without food.
Females lay eggs year round in secluded places, such as behind books or on closet shelves. Eggs are occasionally laid in the open. Silverfish lay only a few eggs at a time but may lay several batches over a period of weeks. The eggs are whitish, oval, and about 1/32 inch long. They hatch in two to eight weeks, the hatching time depending on temperature.
Firebrats lay about 50 eggs one at a time and will lay several batches. The eggs are soft, white and opaque, when laid. They will later have a yellowish tinge. Firebrat eggs hatch in about two weeks. Both insects reach maturity in 3 to 24 months. Their rate of growth depends on temperature and humidity.
Control
The sprays should be applied to floors and wall moldings, behind drawers, under furniture, cracks and crevices, and the floor and ceiling of attics. Outside, treat eaves, mulched flower beds, and storage sheds. Control may not be immediate because hiding insects must come out and contact spray residue. Ten days to two weeks may be required to determine whether or not control has been achieved.
Dusts of the recommended materials may be used for treating walls, voids, crawl spaces, and attics. Space sprays of pyrethrins are useful for controlling exposed insects. See Table 1 and Table 2.
Insecticides labeled for Homeowner Use.
Formulation |
Common Name |
Trade Name |
Signal Word |
Pest |
Crack and Crevice |
||||
Aerosol |
Prallethrin (0.03%), Esfenvalerate (0.05%), MGK-264 synergist (0.3%) |
Ortho Roach, Ant & Spider Killer |
Warning |
silverfish |
| Aerosol | Pyrethrins, MGK-264, Permethrin |
Ortho Ant-B-Gon |
Caution |
silverfish |
Emulsifiable Concentrate |
Beta-Cyfluthrin |
Bayer Power Force Carpenter Ant & Termite Killer Plus |
Caution |
silverfish |
Ready-to-Use |
Cyfluthrin |
Bayer Advanced Home, Home Pest Control Indoor & Outdoor Insect Killer |
Caution | silverfish |
Indoor Surface Treatment |
||||
Aerosol |
Prallethrin (0.03%), Esfenvalerate (0.05%), MGK-264 synergist (0.3%) |
Ortho Roach, Ant & Spider Killer |
Warning |
silverfish |
| Aerosol | Pyrethrins, MGK-264, Permethrin |
Ortho Ant-B-Gon |
Caution |
silverfish |
Ready-to-Use |
Cyfluthrin |
Bayer Advanced Home, Home Pest Control Indoor & Outdoor Insect Killer |
Caution |
silverfish |
Outdoor Barrier |
||||
Aerosol |
Prallethrin (0.03%), Esfenvalerate (0.05%), MGK-264 synergist (0.3%) |
Ortho Roach, Ant & Spider Killer |
Warning |
silverfish |
Emulsifiable Concentrate |
Beta-Cyfluthrin |
Bayer Power Force Carpenter Ant & Termite Killer Plus |
Caution |
silverfish |
Emulsifiable Concentrate |
Bifenthrin | Ortho Termite & Carpenter Ant Killer | Caution | silverfish |
Emulsifiable Concentrate |
Malathion | Ortho Malathion 50 Plus Insect Spray |
Warning | silverfish |
| Granule | Carbaryl | Ortho Bug-B-Gon Multipurpose Insect Killer Ready-to-Use Granules | Caution | silverfish |
Ready-to-Use |
Cyfluthrin |
Bayer Advanced Home, Home Pest Control Indoor & Outdoor Insect Killer |
Caution |
silverfish |
Outdoor Broadcast |
||||
Emulsifiable Concentrate |
Beta-Cyfluthrin |
Bayer Power Force Carpenter Ant & Termite Killer Plus |
Caution |
silverfish |
Emulsifiable Concentrate |
Malathion | Ortho Malathion 50 Plus Insect Spray |
Warning | silverfish |
Ready-to-Use |
Cyfluthrin |
Bayer Advanced Home, Home Pest Control Indoor & Outdoor Insect Killer |
Caution |
silverfish |
Insecticides labeled for Commercial Use on booklice (Psocids).
Formulation |
Common Name |
Trade Name |
Signal Word |
Pests |
Crack and Crevice
|
||||
| Aerosol | Acephate | PT Orthene Crack & Crevice Pressurized Residual (Whitmire Micro-gen) |
Caution | booklice, silverfish |
| Aerosol | Cyfluthrin | PT Cy-Kick Crack & Crevice Pressurized Residual (Whitmire Micro-gen) |
Caution | booklice, silverfish |
| Aerosol | Cyfluthrin | PT Cy-Kick CS Pressurized Crack & Crevice Residual (Whitmire Micro-gen) |
Caution | booklice, silverfish |
| Aerosol | Lambda-Cyhalothrin | PT 221L (Whitmire Micro-gen) |
Caution | booklice, silverfish |
Aerosol |
Pyrethrins and Others | PT 565 Plus XLO (Whitmire Micro-gen) |
Caution | booklice, silverfish |
| Aerosol | Pyrethrins and Others | PT Microcare Pressurized Pyrethrum Capsule Suspension (Whitmire Micro-gen) |
Caution | booklice, silverfish |
Aerosol |
Pyrethrins (0.5%), PBO (4.0%) | PT P. I. Contact Insecticide (Whitmire Micro-gen) |
Caution | booklice, silverfish |
| Bait | Hydramethylnon | Eclipse (Zoecon) |
Caution | silverfish |
| Bait | Hydramethylnon | MaxForce Fine Granule Insect Bait | Caution | silverfish |
| Bait | Hydramethylnon | MaxForce Granular Insect Bait (6 lb) | Caution | silverfish |
| Bait | Hydramethylnon | MaxForce Granular Insect Bait (25 lb) | Caution | silverfish |
| Bait | Orthoboric Acid | Niban FG | Caution | silverfish |
| Bait | Orthoboric Acid | Niban Granular Bait | Caution | silverfish |
| Bait | Orthoboric Acid | Snuffer (Nisus) |
Caution | silverfish |
| Dust | Boric Acid | PT Perma Dust Pressurized Boric Acid Dust (Whitmire Micro-gen) |
Caution | booklice, silverfish |
| Dust | Deltamethrin | DeltaDust (Aventis) |
Caution | silverfish |
| Dust | Disodium Octaborate Tetrahydrate | NiBor-D (Nisus) |
Caution | silverfish |
| Dust | Pyrethrins | PT Tri-Die Silica & Pyrethrum Dust (Whitmire Micro-gen) |
Caution | booklice, silverfish |
| Dust | Pyrethrins and Others | PT Tri-Die Pressurized Silica & Pyrethrin Dust (Whitmire Micro-gen) |
Warning | booklice, silverfish |
| Dust | Pyrethrins, PBO, Silica Gel | Drione (Aventis) |
Caution | silverfish |
Emulsifiable Concentrate |
Bifenthrin |
Talstar F Insecticide/Miticide (FMC) |
Caution |
silverfish |
Emulsifiable Concentrate |
Bifenthrin |
Talstar Insecticide/Miticide (FMC) |
Caution |
silverfish |
Emulsifiable Concentrate |
Cyfluthrin | PT Cy-Kick CS Controlled Release Cyfluthrin (Whitmire Micro-gen) |
Caution | booklice, silverfish |
Emulsifiable Concentrate |
Cypermethrin |
Cynoff EC (FMC) |
Caution | silverfish |
Emulsifiable Concentrate |
Cypermethrin |
Cynoff Power Spray Insecticide (FMC) |
Warning |
silverfish |
Emulsifiable Concentrate |
Cypermethrin |
Cynoff WP (FMC) |
Warning |
silverfish |
Emulsifiable Concentrate |
Cypermethrin |
Cynoff WSB (FMC) |
Warning |
silverfish |
Emulsifiable Concentrate |
Cypermethrin |
Prevail FT Termiticide (FMC) |
Caution | silverfish |
Emulsifiable Concentrate |
Permethrin |
Dragnet SFR Termiticide/Insecticide (FMC) |
Caution | silverfish |
| Emulsifiable Concentrate | Prallethrin | PT ULD SPy-300 (Whitmire Micro-gen) |
Caution | silverfish |
| Emulsifiable Concentrate | Propetamphos | Catalyst (Zoecon) |
Warning | silverfish |
| Emulsifiable Concentrate | Pyrethrins | PT ULD BP-300 (Whitmire Micro-gen) |
Caution | booklice |
| Emulsifiable Concentrate | Pyrethrins and Others | PT Microcare CS Controlled Release Pyrethrum (Whitmire Micro-gen) |
Caution | booklice, silverfish |
| Emulsifiable Concentrate | Pyrethrins and Others | PT ULD BP-100 (Whitmire Micro-gen) |
Caution | booklice, silverfish |
| Emulsifiable Concentrate | Pyrethrins (0.5%), PBO (5.0%) | PT ULD BP-50 (Whitmire Micro-gen) |
Caution | silverfish |
Emulsifiable Concentrate |
Pyrethrins (0.5%), PCO (5.0%) |
Pyrenone 50 (Aventis) |
Caution | silverfish |
Emulsifiable Concentrate |
Pyrethrins (2.5%), PBO (12.5%) |
Synerol Insecticide (Aventis) |
Caution |
silverfish |
| Wettable/ Soluble Powder | Cyfluthrin | Tempo 20 WP (Bayer) |
Caution | silverfish |
| Wettable/ Soluble Powder | Tralomethrin | Saga WP Insecticide (Aventis) |
Warning | silverfish |
Indoor Space Treatment
|
||||
| Aerosol | Pyrethrins and Others | PT 565 Plus XLO (Whitmire Micro-gen) |
Caution | booklice, silverfish |
| Aerosol | Pyrethrins and Others | PT Pro-Control (Whitmire Micro-gen) |
Caution | silverfish |
| Aerosol | Pyrethrins and Others | PT Pro-Control Plus (Whitmire Micro-gen) |
Caution | silverfish |
| Aerosol | Pyrethrins (0.5%), PBO (4.0%) |
PT P. I. Contact Insecticide (Whitmire Micro-gen) |
Caution | booklice, silverfish |
| Emulsifiable Concentrate | Prallethrin | PT ULD SPy-300 (Whitmire Micro-gen) |
Caution | silverfish |
| Emulsifiable Concentrate | Pyrethrins | PT ULD BP-300 (Whitmire Micro-gen) |
Caution | booklice |
| Emulsifiable Concentrate | Pyrethrins and Others | PT ULD BP-100 (Whitmire Micro-gen) |
Caution | booklice, silverfish |
| Emulsifiable Concentrate | Pyrethrins (0.5%), PBO (5.0%) | PT ULD BP-50 (Whitmire Micro-gen) |
Caution | silverfish |
| Emulsifiable Concentrate | Pyrethrins (0.5%), PCO (5.0%) | Pyrenone 50 (Aventis) |
Caution | silverfish |
| Emulsifiable Concentrate | Pyrethrins (1.0%), PBO (5.0%) | Pyrenone 100 (Aventis) |
Caution | silverfish |
Emulsifiable Concentrate |
Pyrethrins (2.5%), PBO (12.5%) | Synerol Insecticide (Aventis) |
Caution |
silverfish |
Indoor Surface Treatment
|
||||
Aerosol |
Acephate | PT Orthene Crack & Crevice Pressurized Residual (Whitmire Micro-gen) |
Caution |
booklice, silverfish |
Aerosol |
Cyfluthrin |
PT Cy-Kick CS Pressurized Crack & Crevice Residual (Whitmire Micro-gen) |
Caution |
silverfish |
| Aerosol | Pyrethrins and Others | PT Microcare Pressurized Pyrethrum Capsule Suspension (Whitmire Micro-gen) |
Caution | booklice, silverfish |
| Dust | Pyrethrins | PT Tri-Die Silica & Pyrethrum Dust (Whitmire Micro-gen) |
Caution | booklice, silverfish |
Emulsifiable Concentrate |
Bifenthrin |
Talstar F Insecticide/Miticide (FMC) |
Caution |
silverfish |
Emulsifiable Concentrate |
Bifenthrin |
Talstar Insecticide/Miticide (FMC) |
Caution |
silverfish |
Emulsifiable Concentrate |
Cyfluthrin |
PT Cy-Kick CS Controlled Release Cyfluthrin | Caution | booklice, silverfish |
Emulsifiable Concentrate |
Cypermethrin |
Cynoff EC (FMC) |
Caution | silverfish |
Emulsifiable Concentrate |
Cypermethrin |
Cynoff Power Spray Insecticide (FMC) |
Warning |
silverfish |
Emulsifiable Concentrate |
Cypermethrin |
Cynoff WP (FMC) |
Warning |
silverfish |
Emulsifiable Concentrate |
Cypermethrin |
Cynoff WSB (FMC) |
Warning |
silverfish |
| Emulsifiable Concentrate | Cypermethrin |
Prevail FT Termiticide (FMC) |
Caution | silverfish |
| Emulsifiable Concentrate | Deltamethrin | Suspend SC Insecticide (Aventis) |
Caution | silverfish |
Emulsifiable Concentrate |
Permethrin |
Dragnet SFR Termiticide/Insecticide (FMC) |
Caution |
silverfish |
| Emulsifiable Concentrate | Pyrethrins and Others | PT Microcare CS Controlled Release Pyrethrum (Whitmire Micro-gen) |
Caution | booklice, silverfish |
| Emulsifiable Concentrate | Pyrethrins (0.5%), PCO (5.0%) | Pyrenone 50 (Aventis) |
Caution | silverfish |
| Emulsifiable Concentrate | Pyrethrins (1.0%), PBO (5.0%) | Pyrenone 100 (Aventis) |
Caution | silverfish |
Emulsifiable Concentrate |
Pyrethrins (2.5%), PBO (12.5%) |
Synerol Insecticide (Aventis) |
Caution |
silverfish |
| Wettable/ Soluble Powder | Cyfluthrin | Tempo 20 WP (Bayer) |
Caution | silverfish |
| Wettable/ Soluble Powder | Tralomethrin | Saga WP Insecticide (Aventis) |
Warning | silverfish |
Outdoor Barrier
|
||||
| Aerosol | Acephate | PT Orthene Crack & Crevice Pressurized Residual (Whitmire Micro-gen) |
Caution | silverfish |
Aerosol |
Cyfluthrin | PT Cy-Kick Crack & Crevice Pressurized Residual (Whitmire Micro-gen) |
Caution |
booklice, silverfish |
Aerosol |
Cyfluthrin |
PT Cy-Kick CS Pressurized Crack & Crevice Residual (Whitmire Micro-gen) |
Caution |
silverfish |
| Aerosol | Lambda-Cyhalothrin | PT 221L (Whitmire Micro-gen) |
Caution | booklice, silverfish |
| Bait | Hydramethylnon | Eclipse (Zoecon) |
Caution | silverfish |
| Bait | Orthoboric Acid | Niban FG | Caution | silverfish |
| Bait | Orthoboric Acid | Niban Granular Bait | Caution | silverfish |
| Dust | Deltamethrin | DeltaDust (Aventis) |
Caution | silverfish |
| Emulsifiable Concentrate | Bifenthrin |
Talstar F Insecticide/Miticide (FMC) |
Caution |
silverfish |
Emulsifiable Concentrate |
Bifenthrin |
Talstar Insecticide/Miticide (FMC) |
Caution |
silverfish |
| Emulsifiable Concentrate | Cyfluthrin | PT Cy-Kick CS Controlled Release Cyfluthrin | Caution | silverfish |
| Emulsifiable Concentrate | Cyfluthrin | Tempo SC Ultra (Bayer) |
Danger | silverfish |
Emulsifiable Concentrate |
Cypermethrin |
Cynoff EC (FMC) |
Caution | silverfish |
Emulsifiable Concentrate |
Cypermethrin |
Cynoff Power Spray Insecticide (FMC) |
Warning |
silverfish |
Emulsifiable Concentrate |
Cypermethrin |
Cynoff WP (FMC) |
Warning |
silverfish |
Emulsifiable Concentrate |
Cypermethrin |
Cynoff WSB (FMC) |
Warning |
silverfish |
| Emulsifiable Concentrate | Cypermethrin |
Prevail FT Termiticide (FMC) |
Caution | silverfish |
| Emulsifiable Concentrate | Deltamethrin | Suspend SC Insecticide (Aventis) |
Caution | silverfish |
| Emulsifiable Concentrate | Permethrin | Astro Insecticide (FMC) |
Caution | silverfish |
| Emulsifiable Concentrate | Permethrin | Dragnet SFR Termiticide/Insecticide (FMC) |
Caution |
silverfish |
| Emulsifiable Concentrate | Pyrethrins | Kicker (Aventis) |
Caution | silverfish |
Emulsifiable Concentrate |
Pyrethrins and Others | PT Microcare CS Controlled Release Pyrethrum (Whitmire Micro-gen) |
Caution | booklice, silverfish |
| Granule | Deltamethrin | DeltaGard G (Aventis) |
Caution | silverfish |
| Wettable/ Soluble Powder | Cyfluthrin | Tempo 20 WP (Bayer) |
Caution | silverfish |
Outdoor Broadcast
|
||||
| Bait | Hydramethylnon | Eclipse (Zoecon) |
Caution | silverfish |
| Bait | Hydramethylnon | MaxForce Fine Granule Insect Bait | Caution | silverfish |
| Bait | Hydramethylnon | MaxForce Granular Insect Bait (6 lb) | Caution | silverfish |
| Bait | Hydramethylnon | MaxForce Granular Insect Bait (25 lb) | Caution | silverfish |
| Bait | Orthoboric Acid | Niban Granular Bait | Caution | silverfish |
Emulsifiable Concentrate |
Bifenthrin |
Talstar F Insecticide/Miticide (FMC) |
Caution | silverfish |
| Emulsifiable Concentrate | Bifenthrin |
Talstar Insecticide/Miticide (FMC) |
Caution | silverfish |
| Emulsifiable Concentrate | Cyfluthrin | Tempo SC Ultra (Bayer) |
Danger | silverfish |
| Granule | Deltamethrin | DeltaGard G (Aventis) |
Caution | silverfish |
| Wettable/ Soluble Powder | Cyfluthrin | Tempo 20 WP (Bayer) |
Caution | silverfish |
Voids/Attics
|
||||
| Aerosol | Acephate | PT Orthene Crack & Crevice Pressurized Residual (Whitmire Micro-gen) |
Caution | booklice, silverfish |
| Aerosol | Pyrethrins and Others | PT 565 Plus XLO (Whitmire Micro-gen) |
Caution | silverfish |
| Aerosol | Pyrethrins (0.5%), PBO (4.0%) |
PT P. I. Contact Insecticide (Whitmire Micro-gen) |
Caution | booklice, silverfish |
| Bait | Hydramethylnon | Eclipse (Zoecon) |
Caution | silverfish |
| Bait | Hydramethylnon | MaxForce Fine Granule Insect Bait | Caution | silverfish |
| Bait | Hydramethylnon | MaxForce Granular Insect Bait (6 lb) | Caution | silverfish |
| Bait | Hydramethylnon | MaxForce Granular Insect Bait (25 lb) | Caution | silverfish |
| Bait | Orthoboric Acid | Niban FG | Caution | silverfish |
| Bait | Orthoboric Acid | Niban Granular Bait | Caution | silverfish |
| Bait | Orthoboric Acid | Snuffer (Nisus) |
Caution | silverfish |
| Dust | DeltaDust (Aventis) |
DeltaDust (Aventis) |
Caution | silverfish |
| Dust | Disodium Octaborate Tetrahydrate | NiBor-D (Nisus) |
Caution | silverfish |
| Dust | Pyrethrins | PT Tri-Die Silica & Pyrethrum Dust (Whitmire Micro-gen) |
Caution | booklice, silverfish |
| Dust | Pyrethrins and Others | PT Tri-Die Pressurized Silica & Pyrethrin Dust (Whitmire Micro-gen) |
Warning | booklice, silverfish |
| Dust | Pyrethrins, PBO, Silica Gel | Drione (Aventis) |
Caution | silverfish |
Footnotes
This document is Fact Sheet ENY-225, a series of the Entomology and Nematology Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Revised: January 2003.
P. G. Koehler, professor, D. Branscome, graduate assistant, and F. M. Oi, assistant extension scientist, Department of Entomology and Nematology, Institute of Food and Agricultural Sciences, University of Florida, Gainesville.
The use of trade names in this publication is solely for the purpose of providing specific information. UF/IFAS does not guarantee or warranty the products named, and references to them in this publication does not signify our approval to the exclusion of other products of suitable composition. All chemicals should be used in accordance with directions on the manufacturer's label. Use pesticides safely. Read and follow directions on the manufacturer's label.
The Institute of Food and Agricultural Sciences (IFAS) is an Equal
Opportunity Institution authorized to provide research, educational
information and other services only to individuals and institutions
that function with non-discrimination with respect to race, creed,
color, religion, age, disability, sex, sexual orientation, marital
status, national origin, political opinions or affiliations.
For more information on obtaining other extension publications,
contact your county Cooperative Extension service.
U.S. Department of Agriculture, Cooperative Extension Service,
University of Florida, IFAS, Florida A. & M. University Cooperative
Extension Program, and Boards of County Commissioners Cooperating. Larry Arrington, Dean.
