Week 3 - Day 12 - Fabric Pests

ESSENTIAL READING BEFORE COMMENCEMENT OF COURSE:

Urban Pest Management in Australia: 2004 Edition, UNSW Press, Sydney

by J Gerozisis and P Hadlington - Chapter 11 - Pages 133 to 140.

Chapter 11 –Household Pests - pests of fabric and paper - clothes moths - structure - life cycle - habits - clothes moths as pests - clothes moth control - carpet beetles - structure - life cycle - habits - carpet beetles as pests - control of clothes moths and carpet beetles - non-chemical methods of prevention - chemical control - surface sprays - space sprays - dusts - other methods - silverfish - structure - life cycle - habits - silverfish as pests - control of silverfish - non-chemical methods of prevention and control - chemical control - surface sprays - space sprays - dusts - booklice - structure - life cycle - habits - booklice as pests - control of booklice

Pest status:

The term "Fabric Pests" is used to describe those insects which have the ability to feed on keratin, a proteinaceous constituent of wool and other animal hair.  There are approximately 30 species of moth larva, 15 species of beetle larva and hundreds of species of biting lice associated with birds known or suspected to be able to digest keratin.  These are the only animals which can digest it.  Silverfish, which are usually included in the category of fabric pests, seldom injure wool or other fibres of animal origin.
The economically important fabric pests are found in the two main groups: carpet beetles and clothes moths.  In both groups, it is only the larva which causes the damage.

Although they prefer keratin - containing substances such as wool, hair and feathers, carpet beetles and clothes moths will also attack other fabrics such as cotton, silk, linen and synthetics if the fabrics are contaminated with substances of nutritional value such as urine, perspiration, beer, milk or fruit juice.  Clean processed wool cannot support the normal life cycle of the clothes moth unless it is contaminated with certain nutritional supplements.

Apart from carpet beetles and clothes moths, there are many other insect species, unable to digest keratin, but still able to cause damage by chewing through keratin-containing fabric.  These include termites, cockroaches, crickets, silverfish, psocids (book lice) and some dermestids.

Pest species:

Variegated carpet beetle -                            Anthrenus verbasci
Black carpet beetle -                                   Attagenus unicolor
Casemaking clothes moth -                            Tinea dubiella
Webbing clothes moth -                                Tineola bisselliella
Tapestry moth -                                          Trichophaga tapetzellla
Silverfish eg.                                               Ctenolepisma longicaudata

CARPET BEETLES
Variegated carpet beetle
This species infests the normal range of goods attacked by carpet beetles including carpets, woollens, silks, hides, feathers, horn and bone as well as plant products such as rye meal, corn and red pepper.  These insects are more correctly classified as scavengers being quite common in birds nests and favouring dead insects and spiders as a food source.

In common with other carpet beetles, this species will feed on cottons, linens and synthetic fibres if they have been contaminated with any of the substances previously listed.  It is important to realise that it is only the larval stage which damages fabrics, the adult beetles feed on pollen from flowers.
Description
A number of varieties exist differing in shape, size, colour and pattern of the scales but, in general, the adults are 2-3mm long with a varied pattern of white, brown and yellow scales on the back and fine, long greyish-yellow scales below.  The mature larva is 4-5 mm long with a series of light and dark brown transverse stripes.  The larva is broadest near the rear and narrows towards the front, unlike other carpet beetles.
Life History
The female lays about 40 eggs.  Usually there are 7 to 8 larval instars but this may vary from 5 to 16.
Egg -- Larva -- Pupa -- Adult
Time: Three month to five months.

BLACK CARPET BEETLE
This is a very prolific pest in many parts of the world and like the variegated carpet beetle, will feed on a wide range of materials including hair, fur, hides, horns, woollen products and plant materials such as cereals and stored grain and nuts.
When they feed on woollen materials they tend to be surface feeders usually eating the nap from the fabric and leaving the base threads alone.  When feeding on fur, hairs are cut at the base leaving the hide bare in appearance.  However, they are capable of eating large, irregular holes through any suitable base material.  The larva may also burrow through packaging material in order to gain food.  Cast larval skins and frass in the form of minute, irregular pellets can be frequently found in the fabric under attack.
Description
The adult black carpet beetles are 2.8 - 5 mm long, shiny black and dark brown, with brownish legs.  The fully grown larva is narrow, up to 8 mm in length and tapers towards the rear, terminating in a tuft of long hairs, Short, stiff hairs cover the body.  The colour varies from light brown to almost black.
Life History
The female lays 50 -100 eggs over a period of approximately three weeks.  The eggs are deposited in accumulations of lint, under and behind skirting boards, in cracks, iri air ducts and other dark, protected places.  There may be 5 to 11 larval instars or even 20 under favourable conditions.
Egg -- Larva -- Pupa -- Adult
Time: Nine months to fifteen months.

CASEMAKING CLOTHES MOTH
This is a very common fabric pest in Australia but often goes undetected by the householder.  It is especially fond of hair and feathers but will also feed on spices, tobacco, hemp and skins.  Its common name is derived from the small silken case that the larva spins about its body incorporating fragments of the larval food material and carries about whenever it feeds with its head and legs thrusting out in front.  Often the larva leaves the fabric or carpet to pupate, taking the case with it and pupating inside.  The case may be seen loosely, attached to walls or ceilings and may be the first indication of an infestation.  Pupation takes place within the case after both ends have been sealed with silk.
Description
The adult moth has a length of about 6.5 mm with a wingspan of about 12 mm.  They are a shiny, greyish - yellow or brown in colour.  Each forewing bears three dark spots but these may rub off with age.  The second pair of wings are lighter in shade and silky in appearance.  Both wings are fringed.
The larva is soft bodied, about 12 mm long and glistening white or slightly vellow in colour.  The head is dark brown and the segment behind the head bears a shiny brown plate.
Life History
The female lays about 50 eggs 0.4 - 0.8 mm in length.  These hatch within 4 to 7 days.  The larval stage may last from 70 to 90 days with a pupation time of 9 to 1-9 days.  The adult stage is short lived lasting onl) 4 to 6 days.
Egg --  Larva --  Pupa --  Adult
Time:  Three months to four months.

WEBBING CLOTHES MOTH
This moth can be very destructive and may be found feeding on clothes, carpets, rugs, upholstered furniture, furs, stored wool, animal bristles and piano felts.  In nature it feeds on pollen, hair, feathers, wool, fur, dead insects and dried animal remains.  Damage usually occurs in dark, hidden areas but sometimes the larvae are very active or may be seen crawling on clothes or on the floor beneath badly infested furniture.  Some larvae may spin a small, frail, silken tube or tunnel, incorporating into the silk some fibres, excrement or cast skins.  They then feed within the confines of the tube.  Some may merely spin flat mats while others may leave the webbing and crawl about unprotected.  The feeding tubes and silken mats make up the webbing that characterises an infestation.
Description
The adult moth has a length of  about  10  mm  with a wingspan of about 12 mm.  The top of the head is covered with bristling, reddish-brown hairs while the wings are uniformly golden buff-coloured without any markings.  Both wings are fringed.  The larva is approximately 12 mm long, thinly coated with fine white hairs and has a shiny light to dark brown head capsule.
Life History
The adult female may lay from 100 to 300 eggs throughout its life span.  These eggs are oval, pearly - white in colour and between 0.4 - 0.8 mm in length.  They require 7 to 10 days to hatch.  The larval stage varies from 35 days to 2½ years in duration whereas the pupal stage lasts from 8 to 40 days.  The adults live from 15 to 30 days.
Egg -- Larva -- Pupa -- Adult
Time: Two months to three years.

TAPESTRY MOTH (OR CARPET MOTH)
This species is not as common as the previous two.  Its entire life cycle is similar to that of the casemaking clothes moth.  The larvae prefer coarser and heavier fabrics than the other two species being commonly found in old woollens, horsehair, feltings, furs and feathers.  They construct burrows or silk-lined galleries in all directions throughout the infested materials.  The pupal case is spun of silk mixed with pieces of the larval food and is noticeably rough.

Description
The adult is larger  than  both  the  casemaking and webbing clothes moth, being 8.5 - 13 mm in length.  The wingspan is nearly 25 mm.  The basal third of the forewing is black while the remainder is mottled white, black and grey.  The hind wings are uniformly pale grey.  Both are fringed.  The adult head is white.  When fully grown, the larva is about 16 mm long, glistening white with a dark head capsule.
Life History
The female moth will lay from 60 to 100 eggs.  The eggs are similar to the other two species.  The larvae will live throughout the summer undergoing 4 to 6 moults.  There are usually more than two generations per year.
Egg -- Larva -- Pupa -- Adult
Time: Three months to six months.

SILVERFISH
Silverfish are nocturnal insects that may occur aimost anywhere in a home.  They are fast moving and are sometimes only seen when they are trapped in washbasins and bathtubs from which they cannot climb out.
Silverfish feed on any human food and in addition, may feed on starch paste, glue, starched cotton, linen, silk, certain synthetic fibres and paper products to which they are attracted by sizing or paste.  They seldom injure wool, hair or other fibres of animal origin.
Description
The young and adult look exactly alike except that the young are smaller.  The maximum size for the adult stage ranges from approximately 12 to 15 mm.  They are generally silvery-grey in colour, with three long tails at the back and a pair of long antennae at the front.  All silverfish are wingless.
Life History
The female deposits an average of 50 eggs in her lifetime.  These are deposited in cracks and crevices around the house.  The eggs are elliptical, nearly white and about 1 mm long.  The insect may continue to grow for well over 3 years, moulting every 2 or 3 weeks.
Egg --  Instars --  Adult
Time:  Three months to three years.

Cultural controls:   sanitation, housekeeping

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