Booklice and Silverfish Booklice and Silverfish
Booklice and Silverfish1
P. G. Koehler, D. Branscome, and F. M. Oi2Booklice
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.
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CREDITS: James Castner, University of Florida
Figure 1. 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.
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CREDITS: James Castner, University of Florida
Figure 2. 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 .
Table 1. 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
Table 2. 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
1. 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 2003.2. 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.
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