A GUIDE TO MORE THAN 350 PESTS OF HOME, GARDEN, FIELD, AND FOREST
GOLDEN NATURE GUIDES
BIRDS • FLOWERS • INSECTS • TREES • SPIDERS REPTILES AND AMPHIBIANS • STARS • MAMMALS • SEASHORES
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GoLDEN, GoLDEN NATURE GUIDE, and GOLDEN PREss® a re t rademarks of Western Publishi ng Compa ny, I nc.
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INsE�T PE
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by G E ORG E S . F I C H T E R M.Sc., Entomology North Carolina State College
Raleigh, North Carolina
U nder the Editorship of
H E RBERT S . ZIM, Ph. D .
Illustrated by
N I C H O LAS S TRE K A LOV S K Y
A GOLDEN NATURE GUIDE
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GOLDEN PRESS • NEW YORKWestern Publishing Company, Inc. Racine, Wisconsin
FO R E W O R D
Despite modern technology, m a n sti l l depends wholly on the products of n ature for s u rviva l . Hence the battle to control insect pests is a never-e n d i n g necessity .
T h i s boo k d escribes more than 350 pests that a re fou n d i n m i d d l e North America. The i l l ustrations, s k i l l fully rendered by N icholas Stre kalovsky, wil l h e l p i d e n tify the pest, i t s life stages, a n d the kind of d a m ag e i t does. The best t i m e s a n d methods o f control are sug gested, but as these vary local ly, get the a dvice of a n entomolog ist or a n agricultural agent before attem pting major controls. The pest g roupings i n this 'book a re based on where usual d a m age occurs . At times when they are a b u n d a nt, h owever, pests become less se lective . A field p'est then, for exa m p le, m ay become bothersome i n gardens. Insecticides a re the best means to get i m m ed iate results, but remem ber: i nsecticides are poisonous. Fol low d i rections and heed all precautions on the l a b e l .
A n u m ber of p e o p l e gave a dvice a n d assista nce in the preparation of this book. These incl uded Dr. J . F . Gates C l a r k e a n d h is staff at the U . S . N ational Museu m . Also o f g reat help were Ro bert H . Nelson a n d m e m bers of the Entomological Society of Am erica . Dr. J e a n L. Laffoon was especially helpfu l, as were Dr. George Anastos, D r. R . M. Baranows ki, Dr. Ralph Crabill, Dr. Richard l. Doutt, Dr. Richard C . Froesch ner, Dr. Herbert W. Levi, D r . Fra n kl i n B. Lewis, a n d Dr. Howard V.
Weem s .
G. S . F. © Copyright 1966 by Western Publishing Company, Inc. All rights reserved, including rights of reproduction and use in any form or by any means, in· eluding the making of copies by any photo process, or by any electronic or mechanical device, printed or written or oral, or recording for sound or vis· ual reproduction or for use in any knowledge retrieval system or device, unless permission in writing is obtained from the copyright proprietor. Produced in the U.S.A. by Western Publishing Company Inc. Published by
CONTENTS
AN I NTRODUCTION TO I N SECT PESTS • . • • • • • 4 N u m ber of i nsects, relatives, a n d development.
CONTROLLING INSECTS . . • . . . • • . • • • • . . . • • • 10
Natural, biological, m echanical, chemical, a n d n e w methods.
HOUSEHOLD PESTS . . . • . . . • . . • 24
INSECTS THAT BITE OR STING . . . • . • . 38
PESTS OF PETS, POULTRY, AND L IVESTOC K • • 48
I N SECT PESTS OF VEGETABLE C ROPS . . . • 61
PESTS OF FLOWERS AND SHRUBS • . . . • • 86
F I E LD A N D FORAGE C ROP PESTS • . . . • • . • 98
PESTS OF FRUITS A N D FRUIT TREES • . • . . . . • • • 120
PESTS OF FOREST A N D SHADE T REES . . . 139
I N SECT PESTS OF STORED PRODUCTS . . . . • . • • 146
SCIENTIFIC NAMES . . • . . . • . . . • • • • • . . . • • • • 154
4
Insects exist in enormous nu m b ers. The averag e insect pop u l ation per sq uare m i l e is estimated to be e q u a l to the total world popul ation of people, a n d in severe outbreaks a pest species far exceeds its normal n u m bers . I n one fly infestatio n, experts P.sti m ated 1 5,000 flies per cow. Bil lions of h u ng ry g rasshoppers m ay darken the s ky a n d devour a l l vegetation in their path . Insect destruction of crops i n the United States ranges from 4 billion to 15 bil lion dollars a n n u a l ly. D a m age to cotton by o n e insect, the Bol l Weevil, a mounts to more tha n 3 00 m i l lion dollars a year. Term ites consume a bout 1 00 m i l l io n dollars' worth of wood structures, whil e forest i nsects destroy more wood tha n d o forest fires. I n sect d a m age cancels out the tota l year ' s efforts of a bout one m i l lion workers .
Fortun ately, less t h a n one percent of the nearly o n e m i l lion i nsect s pecies are pests o f m a n, h i s dom estic a n i m als, and usefu l pla nts. Of the 1 00,000 i nsect spe cies that occur i n the U n ited States, o n ly a bout 600 a re considered serious pests.
D a m a g e done by i nsect pests is easy to a p p raise. The value of beneficial species is h a rder to esti m ate . Bees, wasps, flies, b utterflies, a n d othe r insects pol l i n ate flowers that p rovide us with fruits a n d vegeta bles. Honey, wax, a n d s i l k a re im porta nt c o m m e rcial products obtained from i nsects . Some i nsect species are vital l i n k s i n the food c h a i n s of fishes, b i rds, and oth er a n i m a l s . Other i nsects a re parasites or pred ators of d a m a g i n g pests or are scavengers of a n i m a l a n d veg etable debris. Control measu res used a g a i nst h a rmful i nsects m ust be weig hed ca refu lly to d eterm i ne t h e u lti m ate effect on a l l l ivi ng things, i n c l u d i n g m a n .
6
PARTS OF A TYPICAL I N SECT
INSECTS AND THEIR C LOSE RELATIVES are a rth ro
pods, or "jointed-legged " a n i m als, a large group that incl udes more than 85 percent of the known s pecies of a n i m a l s . About 90 percent of all the a rth ropods are i nsects. An i nsect's body has th ree d istinct reg ions head, thorax, a n d abdomen. Attached to its thorax are three pairs of legs, and in most species, two pairs of wings. Its head bears a pair of antennae. This com bination of features d istinguishes insects (class I n secta) from such closely related land a n i m a l s as spiders, tic ks, m ites, centipedes, a n d m i l l ipedes.
The l a rgest g roups of insects are called orders. Six teen orders of i nsects that include im porta nt pest species are s u m m arized on page 7, a s a re the identifyin g c h a r acteristics of the other arth ropod classes .
Orders a re d ivided i nto families a n d the fa m ilies into genera and species. An insect's scientific n a m e usually consists of two words, its genus a n d s pecies. The scien tific n a m es of the pests i n this book are listed on pages 1 54-156. The common n a m es used i n the text are those approved by the Entomolog ical Society of America.
MAJOR ORDERS OF INSECTS
CLASS NAME OF ORDER COMMON EXAMPLES WINGS, MOUTHPARTS
Thysanura silverfish, firebrots wingless; chewing
Collembola springtails wingless; chewing
Orthoptera grasshoppers, crickets, 2 prs. wings or wingless;
cockroaches chewing
Dermaptera earwings 2 prs. wings or wingless;
chewing
lsoptera termites 2 prs. wings or wingless; chewing
Psocoptera barklice, booklice 2 prs. wings or wingless;
chewing Mallophaga chewing lice wingless; chewing Anoplura sucking lice 2 prs. wings or wingless;
< piercing-sucking
.... Thysanoptera thrips 2 prs. wings or wingless; u
w rasping-sucking
"'
� Homoptera aphids, leafhoppers 2 prs. wings or wingless; scales, mealybugs piercing-sucking
Hemiptera bed bugs, stink bugs, wingless; piercing-sucking chinch bugs
Coleoptera beetles, weevils 2 prs. wings or wingless; chewing
Lepidoptera moths, butterflies 2 prs. wings; chewing
(larvaeL sucking, or
siphoning (adults)
Hymenoptera wasps, bees, ants 2 prs. wings or wingless;
sawflies chewing
Diptera mosquitoes, flies, 1 pr. wings; chewing gnats (larvae), piercing-sucking,
or sponging (adults)
Siphonaptera fleas wingless; chewing (larvae),
ARACHNIDA
CHILOPODA
DIPLOPODA
piercing-sucking (adults) CLASSES OF OTHER ARTHROPOD PESTS
spiders, ticks, mites, scorpions
centipedes
millipedes
4 prs. legs; 2 body regions cephalothorax and abdomen; no antennae; chewing or suck ing mouthparts
1 pr. of legs per body segment; 1 pr. of antennae; 2 body re gions-head, trunk; body flat tened; chewing mouthparts 2 prs. of legs per apparent body segment; 1 pr. of anten nae; 2 body regions-head, trunk; body rounded; chewing mouthparts
egg IJ
8
S I LVERFISH g row larger but do not change
in appearance or structure.
youn g a d u l t
I NSECT DEVELOPMENT An insect pest can be con trolled m ost easily at a specific stage of its life h istory, someti mes not the one in which it d oes its g reatest dam age. Destroying the insect's eggs is often the m ost effective control measure. But to d o this you m u st know where a n d when the female lays her eggs. Hence life histories are e m p h asized in this book.
Nym phs are young insects that, as soon as they hatch, rese m b l e m i n iature adults. If the adult has wings, wing buds soon appear on the nym ph 's thorax. These g row each ti m e t h e nymph s heds, or molts, a n d by the time t h e i nsect is m ature, the wings are ful ly developed . Nymphs are active. They com monly live i n the same place a n d h ave the same feed ing habits a s the adults. True bugs, g rasshoppers, cockroaches, and lice are among t h e i nsects that h ave a nym ph stage . These change ( metamorphose) g radually t h roug h th ree d e velopmental stages-egg, nymph, and adult. This type of metamorphosis is called simple. Prim itive i nsects, such as silverfish and springtai ls, a lso d evelop by a s i m p l e m eta morphosis, but there are a l m ost no c h a n ges i n their structure as they g row, only a n increase i n size. Nym phs of some aquatic insects are called naiads; they d iffer considera b ly from adults i n appearance a n d habits but c h a n g e from n a i a d s directly i n t o a d u lts.
egg
CH INCH BUGS h ave three stages, Nym phs rese m b l e a d ults, but Jack wings.
nymphs
JAPANESE BEETLES develop through four d isti nct stages, each differing in a ppear
This is com p l ete metam orphosis.
adult
More kin ds of insects develop throug h a complete meta morphosis. The insect changes in appea ra nce a n d ha bits from o n e stage t o the next through fou r distinct stages-eg g, l a rva, pupa, a n d adult. The egg hatches into a l a rva, an active, feeding stage. The mature l a rva forms a pupa; a resting, or nonfeeding, stage from which the insect emerges as a n a d u lt. Caterpil l a rs a re the crawl i n g l a rvae of b utterflies a n d m oths. They h ave chewing m outhparts. Some a re major pests of pla nts and stored prod ucts. The a d u lts have sucking , or nectar feeding, m outhparts and never d o d a m age. Maggots
a re the l a rvae of flies; g rubs, the l a rvae of beetles. 9
1 0
CONT R O LL I N G I N S ECT S
Insects become pests when they d a m age crops, destroy products, transmit diseases, a re annoying , or in other ways conflict with m an's needs or interests. In man's continuous battle against insect pests through the cen tu ries, no insect species has ever been eradicated, though some h ave been red uced in nu m ber, at least temporari ly. At the same ti me, other pest species have actu a l ly become more abund ant and are now a g reater problem because m an has provided inc reasing ly favor a ble cond itions for them . The modern one-c rop system of agriculture often supplies food for an insect pest in l a rge q uantity over m any square m iles. As new crop plants were introd uced from other countries, their insect pests often came with them, but not the pred atory species that kept the pests under control in their home land . Some varieties of crops are more susceptible to pests than were the origina l wild plants, which over the years developed a deg ree of resistance to insect attack.
NATURAL CONTROLS ord inarily keep insect popula
tions in bal ance. Weather factors, such as temperature and ra infall, limit the d istribution of an insect species, as do such geog raph ic barriers as l a rge bodies of water, deserts, or mountain ranges .
Toads, l izards, frogs, moles, and sh rews are a m ong the many anim als that feed m a inly on insects. Some birds m ay eat their own weight in insects every day. Pred atory insects usu a l ly feed on whatever insects a re availa b le. Larvae of parasitic insects develop in the eggs, young, or a d u lts of other insects. Vi rus, fung us, and bacterial d iseases a lso help hold insect populations in chec k . Man has often upset these natural b a lances.
Beca use i n sect-eati ng birds tend to eat the most available i nsects, they are especially helpful i n control l i n g pests i n outbrea ks.
TACH I N I D FLY
Braconid wasps lay eggs i n aphids or other insects. Larvae develop i n side.
ARMYWORM
The Tach i n i d Fly lays its eggs on the Armyworm. Fly larvae eat o n d soon kill the worm .
These tiny rove beetles feed on maggots. The larvae a l so burrow i nto pupae.
B IOLOGICAL CONTROL is the purposeful use of natural pred ators, parasites, or diseases to kil l o r red uce the population of a pest species. This method has been effective principally in com bating insect pests introd uced from foreig n countries without their natural enemies . Biological controls a re not usually practica l for home g a rdens or simil a r small areas. They a re used most s uccessful ly in orchards and g roves or where large-sca le crop pla n tings a re repeated year after year on the same l a n d . Usua l ly the control species is at fi rst bred a rtificia lly so that it can be introd uced in la rge n u m bers. More than two dozen cases of effective large-scale con trol of i nsect pests have been achieved by this method .
Damage to citrus by the Cottony-cushion Scale in California was virtually eliminated by the introduction, of Veda lia, a n Austra lia n lady beetle. Later, g rove
Parasitic Bracanid Wasp intro d uced from England. Wasp larvae
feed inside I m ported Cabbage- 3.0 in. worm and k i l l it.
Japanese Beetle i s k i lled by
Bacillus papillae, which causes m i l ky d isease. The Hornworm
0.8 in. succumbs to 8 . thuringiensis.
owners beg a n to spray their trees to kill aphids. At the s a m e time they kil led the Vedalia beetles, causing a n outbrea k o f Cottony-cush ion Sca le aga i n . The u s e of b acteria causing m i l ky d isease that ki lls grubs of t h e Japanese Beetle is a nothe r exa m ple o f successful bio logical contro l . Ga m b usias and other top-feed i n g m i n nows a re effective i n t h e control o f m osquito l a rvae . Interesti ng ly, the Chrysolina Beetle was i ntrod uced to western Un ited States from Austra lia to halt the spread
of the K l a m ath weed . 1
Biological controls do not e l i m i n ate a pest species completely. They o n ly reduce the population and thus keep the d a mage low. But biological controls are usually self-ge nerati ng, so a control species, once established, continues to reproduce a n d to remain effective .
PHYS ICAL AND MECHANICAL CONTROLS are the
si m plest, m ost obvious, and at times most effective: wit ness the old-fash ioned fly swatter. Pests of stored prod ucts a re co m m only destroyed by heat or co l d . Few can survive long in a tem perature of 1 2 0 deg rees F. or high er. Cold either kills or stops activity. Dra i n ing off stand ing water to elim inate breed ing places is a stan d a rd mosquito control method, while m any pl ant pests a re killed by flooding. Lig hts a re used to attract some kinds of pests, which may then be electrocuted on charged screens. Pests that col lect in large n u m bers may be l u red to ba its or caught in ditches. The g a rdener who picks J a panese Beetles off his roses by h a n d uses an effective method for small areas.
CULTU RAL CONTROL is an inexpensive method of check ing or preventing damage by insect pests by com bining mechanica l or physical controls with a knowledge of the pest's l ife history. Crop rotation prevents the build-up of a pest popul ation that feeds on one kind of plant. Burying stal ks, weeds, and other resid ues after h arvest destroys eggs, pupae, or hibernating larvae and adults. S i m i la rly, early or late plowing may destroy a particular l ife stage of a pest. Planting and h a rvesting
Golden Regent, a resistant variety of sweet corn.
can sometimes be timed to esca pe periods of egg ·laying or of pest a bund ance. Varieties of p lants re sistant to particul a r pests can be planted . Healthy, vigorously grow ing plants can withstand insect at tac ks better than those that ore wea k or d iseased . Likewise, ani m a ls in good health a re not as g reatly distu rbed by pests.
INSECTICIDES a re poisons used to kill insect pests .
Their g reat advantage is speed . Biologica l control meth ods, while safer and longer lasting, may require severa l seasons to become effective.
More than 3 5 0 million pounds of insecticides are sold a nnua l ly in the United States . Their use increases agricultural yields by an average of a bout 2 5 percent and in many cases prevents complete crop l osses. I n secticides a re hig h l y important, too, in the control of pests that are a n n oying or a re disease carriers .
Most insecticides are d a ngerous to people a n d other animals as well as to pests . Read and fol l ow carefu lly the instruction on labels. Consult a cou nty ag ent or an entomologist or employ the services of a professiona l pest-control operator.
APP L I C AT I ONS of in secticides are rarely made full
stre ngth . Dusts are d ry m ixtures of from 0. 1 percent to 25 percent of the poison mixed with fi n e particles of a n inactive materia l, s u c h as ta lc. Wettable powders are d usts that form a suspension in water fo r sp rayi ng; the powd er m ay consist of from 1 0 to 95 percent i n secticide.
Emulsifiable concentrates, the most common form u l ation for a p p lying insecticid es, consist of oil or a s i m i l a r or ganic solvent conta i n i n g the insecticide and a n emul sifier that aids the mixing of the d ropl ets of oil a n d in secticide in water. T h e co m ponents may sepa rate o n sta n d i n g but can be remixed b y s h a k i n g . Special sol vents, such as kerosene, pine oil, and other liquids of org a n i c compoun ds, are used with th e water-insoluble org a n i c insecticides. Most solvents are toxic to plants, are infla m m a b le, a n d may damage wallpape r, tile, a n d other m aterials. For a l l appl ications, follow printed di rections with care.
Aerosol Bomb
SPRAYERS use a pump to build u p a i r pressure that forces the liquid i n sectic ide from the noz zle. The size of the nozzle open ing creates either a fog l i k e m ist or a steady strea m .
DUSTERS are powered b y h a n d or by motor a n d use e i t h e r a fan or com pressed o i r to force out the d u st in a cloud. AEROSOL BOMBS, t h e most com mon household appl icators, consist of a n i n secticide dis solved i n a l i q uefied gas under h i g h pres sure. A fi n e m i s t is pro duced when these are a l lowed to escape from a s m a l l openi ng. Aerosols o re conve n i e n t but a re relatively expensive.
Bean beetles a n d their larvae (p. 76) feed an the u nderside of leaves. They can be reached with insecticide d usts.
STOMAC H POISONS are used principa lly to k i l l insects
with chewing mouth parts. They m ay be sprayed or d usted d i rectly on the i nsect's food or may be mixed with baits to attract the pests. To be useful a stom ach poison m ust k i l l fairly q u ickly, as the pest is a lready doing d a mage when it ta kes in the insecticide. Too heavy a n appl ication of these chemicals may kill the pla nts . The resid ues are poisonous to m a n a n d domes tic a n i m a l s . Contact insecticides (p. 1 8 ) act as stomach poisons if eate n . Arsenic compou n d s are the m ost com mon inorg a n i c stomach poisons. Paris green (ca lcium a cetoarsen ite) was the fi rst chemical i nsecticide used successfu lly on a large scal e . Lead arsenate, white arsenic ( a rsenious oxide), sodium arsenate, a n d calcium arsenate are other arsenic stomach poisons. Fluori n e compou n d s that a c t as stomach poisons are sodium fluo silicate, sodium fluoride, a n d sodium fluoaluminate
(cryolite) . Thallium sulfate, h i g h ly poisonous, is mixed with food to m a k e ant ba its. Do not store a ny i n secticide where c h i l d ren can reach it. Ma ke certai n the con tain ers are properly labeled a n d marked POISON .
CONTACT I NSECTI C I DES a re sprayed or d usted di rectly o n pests or are spread wh ere pests w i l l pick them u p . They are especia l ly useful i n controlling i nsects with piercing-sucking mouthparts. Al l contact poisons act as stomach poisons ( p . 1 7) if eate n . Most of them a re also poisonous to people and a n i m a l s and thus are a serious hazard if not used a s d i recte d . In excess a m ounts m a n y contact insecticides are poisonous t o pla nts. Some a r e u s e d as fu m i g a nts. Always r e a d the label before even open ing the i nsecticide container. When i n d o u bt obout h ow to use a n i nsecticide safely a n d most effec tively, ask the advice of your dealer or of a county or ag ricultu ra l agent.
Most of the many thousa nds of tradenamed insec ticide for m u l ations belong in the contact-in secticide group. These a re divided i nto the fol lowi ng grou ps inorganics, natural organics or plant poisons, synthetics, a n d oils. Each of these groups is d escri bed separately on the fol lowi n g pages. Most of the contact i n secticides now used h ave appeared since the World War I I de velopment of D DT, the first widely used synth etic or g a n ic i nsecticide.
INORGA N I C CONTACT INSEC TICI DES, consist i n g m a i n ly of
sulfur dusts, m ixtures of lime
a n d sulfur, or sulfur compounds,
were the forst contact poisons used on a large scale and stil l ran k among t h e m ost i m portant.
Sulfur dust i s one of the m a i n chem ical controls f o r m ites, for the crawling stages of scales, and for some k i n d s of caterpil lars. Finely g rou nd sulfur is us able as a wetta ble powder for spray appl ications. Lime-sulfur solution is a l i q u i d, sol uble in
1 8 I NSECTICI DES
water. L i m e-sulfur is a l so dehy drated and sold in concentrated powder form . I t i s used to con trol plant pests such as scales and also as a dip for cattle, sheep, and other l ivestock. Bor deaux mixture is a com b i nation of copper s u l fate and lime in water. In add ition to their use as insecticides, sulfur a n d sul fur compounds are valued as fungicides. I n hot weather, heavy appl ications of s u l f u r w i l l b urn foliage and fru it a n d so m ust be appl ied sparing ly.
N A T U R A L O R G A N I CS were the earliest compounds used i n k i l l i n g insect pests. With t h e ex ception of n i cotine, h i g h l y toxic to man and other m a m mals, they are the least dangerous of the in secticides to use on food plants or in the house.
Nicotine is obtained from the waste leaves of tobacco plants a n d waste tobacco products. It is used principally as nicotine sulfate, with a 40-percent n i co tine content. The 40-percent con centrate is ord i n arily d i l u ted in 800 to 1 ,000 parts of wafer (about one teaspoon to a gal lon) a n d is appl ied as a spray to k i l l aphids or other soft-bod ied in sects. N i coti n e su lfate is used also as a stack dip for control of m ites, ticks, and lice. Finely ground tobacco ste m s a n d leaves are used as a d ust or burned as a f u m igant. N icotine may be added to aerosol form u l ations. Pyrethrum comes from the flowers of several species of chry
santh e m u m s. It is produced com mercia lly from a species g rown i n East Africa. Fast-acti ng pyre thrins ore the "'knockdown " agents i n m ost household sprays, with slower-acti ng DDT or other synthetics o cluolly k i l l i n g the i n sect. Allethrin, produced syn thetical ly, is much the same os pyret hrum i n action.
Rotenone is obta i ned from the dried a n d g rou n d roots of the South Am erican cube and from the roots of two species of der ris that grow in the East I n d i es. As prepared for an i n secticide,
Tobacco plant, source of h i g h ly toxic n i coti ne
rotenone is relatively nontoxic to hu mans, but as a n i n secticide it acts both as a stomach and as a contact poison. Another use of rotenone by biologists is as a poison to e l i m i n ate trash fish i n lakes a n d ponds.
Other bota n icals, or natural organic contact i nsecti cides, in· elude ryania, produced from the pu lverized ste m s a n d roofs of a South American plant. Rya n i a is less tox ic to m a m m a l s than ro tenone and so i s reco m m ended for food pla nts where residues m i g h t be a pro b l e m . Sabadilla, which also has low toxicity, is mode by g r i n d i n g t h e seeds of a li ly-fam i ly plant of Venezuela.
SYNTHETIC ORGA N I C CON TACT INSECT I C I DES a r e t h e
mast i m portant group o f c h e m i cals used today i n the control of i nsect pests. There are two g roupo: ch lori nated hydrocarbons and organo-phosphates.
CHLORINATED HYDROCARBONS DDT is the leader i n the ch lo r i nated h ydrocarbon g r o u p . Though fi rst synthesized i n 1 874, DDT was not recog n ized as an i n secticide u n t i l World War I I , when its i n itial large-sca le use halted a typhus epidemic spread by l ice in I taly. It was later va lu able during the war years i n the control of fl ies and mosqu itoes and came into widespread use in the control of agricultural a n d household pests after the war. DDT is h i g h ly effective in k i l l i n g many kinds of i n sects b u t is relatively nontoxic to aphids, spider m ites, and some other species. Some cockroaches, fl ies, and other i nsects have devel oped resistance to DDT. When an i nsect comes i n contact with DDT, it fi rst appears to lose con trol of its vol u n tary actions; later it becomes paralyzed. Death comes slowly, someti mes several days later. DDT has a rather low toxicity Ia man and other verte brates but may be stored in the fatty tissues of the body a n d cause death months later when the fat reserves are utilized.
DDT is appl ied as a dust, wettable powder, water emul sion, or i n an oil base. Verte brates a bsorb the oil-base DDT most rapidly. DDT is i n soluble i n water. I ts residues may re-20 I NSECTIC IDES
m a i n effective outdoors for many months or even years, i ndoors for even longer. Methoxychlor, related to DDT, is effective aga i n st the Mex ican Bean Beetle and works more rapidly i n k i l l i n g t h e House Fly. TDf ( o r DOD), also a relative of DDT, i s com monly used i n mosqu ito control be cause it is less tox i c than DDT to vertebrates. TOE is a lso less poi sonous to i nsects, however.
Benzene hexachloride (BHC), also i n the c h lori nated-hydro carbon g roup, was d iscovered as a usef u l insecticide about the same time as D DT. BHC k i l l s faster than D D T a n d i s com monly used in the control of crop pests. It has a d isti n ctive m usty odor and sometimes taints food. BHC is usually used as a dust or a wetta ble powder. Lindane is BHC that d i ffers only i n the arrange ment of its atoms, but as it lacks the objectiona b l e heavy odor, it is used more commonly i n houses. Though i t s resid u a l l ife is shorter than DDT's, l indane is about twice as toxic to many i nsects and a p parently is not stored i n the body tissues. Toxa
phene, i n soluble i n water but sol uble i n many org a n i c sol vents, is a n excellent i n sect k i l ler but i s also poisonous Ia verte brates. Toxaphene is one of the most com mon i n secticides for contro l l i n g pests of cotton .
Chlordane, dieldrin, aldrin, endrin, and heptachlor form an oth er group of �losely related chlorinated hydrocarbons. All a re insol uble in water but are solu ble i n m a ny org a n i c solvents.
Scales may be killed with organa phosphate sprays (below and p. 86). Use these i n secticides with g reat care.
They are a lso used i n dust or pellet form , particularly as soil poisons for the control of ter m ites and a n ts. They are h i g h ly effective i nsect killers and are residual. They are also poison ous to vertebrates, i n c l u d i n g m a n and o t h e r m a m mals.
ORGANO- PHOSPHATES
The organo-phasphate group of contact i nsecticides ste m s from chem ical research j u st be fore World War II, when same of these com pounds were devel oped as poisonous gases for use i n warfare. Most of them are ex tremely lethal to m a n and a n i m a l s as wel l as to i n sects. They can be taken i nto the body through the mouth or the s k i n or by i n h a l i n g their f u mes. Resi dues an foods are a sou rce of danger. Because these i n secti cides are very poisonous, they m ust be h a n d led with the great est care.
Parathion, a brown ish -yellow
liquid with a garlic odor, is toq poisonous for household use or for applying near l ivestock a n d pets, but it is w i d e l y u sed on fruit and vegetable crops. Resi dues d i sa p pear rapid ly. Deme ton, a bout as poisonous as para thion, acts as a syste m i c poison, being absorbed by the tissues of the plant. It kills pests that feed on the plant's j u ices without af fecting predators a n d pol l i nators. TEPP, eve n more poisonous than parathion, decom poses ra p i d ly and leaves no residue. It is used regu larly o n food crops.
Malathion, m a s t c o m m a n l y used organa-phosphate, i s not h i g h ly toxic to vertebrates. Ma la thion wi l l k i l l many i n sect species that h ave developed a resista nce to the i n s ecticides of the DDT and ch l o rd a n e g r o u p s . Diozinon, DDVP, ronnel, and dicopthon are ather organo-phosphates that are excellent insect k i l lers. DDVP is the most h i ghly toxic of these chemicals to man and a n im a l s .
Oils are a p p l ied to citrus to k i l l
young stages of P u r p l e Scale ( p . I 33) a n d Citrus Whitefly (p. 136).
OILS, principally petroleum but also some a n i m a l a n d vegeta ble oils, serve as carriers for i n secticides or may b e u s e d as i n secticides them selves. Dormant oils, rather heavy a n d sem ire fi ned, are a p p lied in late wi nter or early spring to trees or s h rubs that ore not i n foliage to k i l l scales, mites, e g g s , a n d some larvae. Summer oils ore lig hter and more h i g h ly refi ned, hence less damaging Ia pla nts; they ore used to control a ph ids, scale i n sects, and mealybugs. As the oils themselves are toxic to plants if applied full strength, they ore m i xed with water by add i n g o n e m u l sifier, such as soap. Th is d i stributes the oil even l y as small droplets. Oil baths may be used to k i l l such parasites as fl eas, l i ce, ticks, and m ites on dom estic a n i m a l s and pels. Form ulations that req u i re shaking with a s m a l l a m o u n t of water before fi n a l m i x i n g o r e c a l l e d miscible o i l s . An emulsible-oil form u l ation con be pou red d irectly i nto the water.
FUMIGANTS ore gases used to k i l l i n sects in enclosures, as i n 2 2 I NSECTICIDES
b u i l d i n g s or conta i ners, i n the soil, or under such tem porary covers as tarpa u l i n s and tents. Many fu m igants are infl a m m able. Nearly all fumigants ore more poisonous Ia m a n t h a n to the i nsects a n d should be used only by a p rofession a l pest-control operator. Their adva ntage is their pe netration to a l l ports of b u i l d i ngs, i nto stored products or plants. They leave n o resid ue. Carbon disulfide (carbon bisul fide), h ig h ly inflam mable, is u sed mainly as a soil f u m igant for a n ts, termites, and gru bs. For i n �oor use it may be m ixed with carbon tetrachloride to reduce the d a n ger of fire or explosion. Dichloropropene a n d dichlaro propane are also used as soil fumigants. Hydrogen cyanide, w h ich has a d i st i n ctive n u tty odor a n d is deadly poisonous, is used to fum igate m i l l s a n d ware houses or fruit trees u n der tents. Methyl bromide, a n o n i n fl a m m a ble f u m igant, is v a l u e d because of its power to penetrate tightly packed material s. Paradichloro benzene ("para " crystals) a n d naphthalene (both sold as moth bolls) vaporize slowly and act as a f u migant a n d a repellent.
REPELLENTS are chem icals that by their odor or taste prevent in sect attacks. They are used m a i n l y to protect man, a n i m a l s, or stored products; less co m m o n l y , p l a n t s . Some repellents are poisonous if touched, eaten, or breathed. Mothballs are repel lents that protect clothes from i n sect damage. Creosote is used as a barrier agai nst craw l i ng i n sects, w h i l e smoke screens ward of! fl ies a n d mosqu itoes. Among the most successfu l of dozens of repellent c h e m i cals ore diethyl toluamide, dimethyl phthalate, a n d ethyl hexanediol. These or ganic chem icals are d i l uted with oils a n d disguised with per f u m es. They are sold under many tradenam es. Most will repel i n sects f o r one to fi v e hours. '' NEW METHODS of combating i nsect pests are being developed every year. Some are usef u l only
i n large-sca le control progra ms, others i n h o m e and garden. Among the m ost pro m i s i n g are sterilants that render insects in capable of reproducing. T h i s m ethod w a s fi rst u s e d with suc cess to control the Screw-worm . Mi l l ions of m a les, steril ized by rad iation, were released in areas of i n festation to male with fe· males, which then prod uced i n fertile eggs. Hormones a r e used to cause a n i n sect to pass from one stage of its develo p m e n t to the next irrespective of season. Thus, pupae can be made to transform i n to adu lts i n m i d winter or larvae may be m a d e t o pupate before t h e y are f u l l grown. I n sect hormones a r e a p · parently harm l ess t o other l iving things. Also safe are such non· toxic insecticides as fi nely grou nd sil ica, which a b rades the outer covering from a n i n sect a n d causes it t o d r y up, or desiccate, as its body fl u i d s escape.
The soil in seed beds can be f u m igated by relea s i n g m ethyl-bro m i d e g a s u n d e r p lastic cover.
widespread in U.S., g ive off a sweet odor when crushed. Travel d efi n i te tra i l s ta fond food.
A RGENT I N E ANTS a re c o m m o n i n southern U . S . ; worst a n t pests i n houses. Prefer sweets but eat oil foods. Bile, do not sti n g .
HOU EHOLD P
I n sect pests may destroy the timbers of a house, tunnel i nto furniture a n d fa brics, or r a i d the contents o f the kitchen, fro m the spice cabinet to the garbage pail. Some k i n d s bite, sting, or tra n s m it diseases. Others are s i m p ly a n noyi ng, u n i nvited guests .
The basic step in control ling household p ests is to keep them out. Screen windows a n d doors, seal crac ks, a n d remove debris in which pests can h i d e or m u ltiply. If pest" i nfestations a re h eavy, persistent, or u nexplain able, services of a professional pest-control operator may be necessary. Make certa i n the man employed represents a licensed, bonded org a n i zation .
Many pests c a n b e recog nized a n d control led with out expert help. Since i nsecticides are poisonous a n d w i l l be u s e d wh ere there a r e people, pets, a n d food, fol l ow ca refu lly the d i rectio ns given on the l a b e l .
THIEF ANTS often l ive i n other onl n ests and feed on larvae. They prefer c h eese, m eals, or other greasy food.
P H A R A O H A N T S a l s o l i k e meal. May nest i n walls a n d then i nvade all parts of house. Poison baits are best control m ethod.
CRAZY ANTS, native to I ndia but now widespread, run 11Craz. i ly" on their long legs. They eat m eat, greasy foods, and sweets.
CORNFIELD ANTS are the com mon " red ants" of northern states. Nest mounds often nu merous on lawns. I nvade houses.
ANTS live in colon ies in the g round, in the fou n d ations
or walls of b u i l d i ngs, beneath bark or stones. A colony conta ins n u m erous workers (sterile fe m a les), one to sev eral queens, a n d a few m a les d uring part of the year. Workers d o not h ave wings, but m a les and fe males are winged at swa r m i n g ti m e . Males d i e after mating, and the q ueens d rop their wings a n d fl n d a place to sta rt a colony. After mating, queens re m a i n ferti le, livi n g a s l o n g as 2 5 yea rs. Queens a re usually several times l a rger t h a n workers, which atte nd their every need . Ants belong to same insect order as bees a n d wasps. They h ave el bowed antennae a n d a thin wai st, disti n g u i s h i n g them from term ites ( p . 2 6 ) .
The most effective control is t o d estroy the n est i f it can b e fou n d . C h emical ba rriers, using a res i d u a l contact i nsecticide, can be placed arou nd fou n d ations of b u i l d i n g s . Workers will ca rry poisoned ba its to the colony and thus kill even the queen.
SOUTHERN FIRE ANTS occur i n warm parts o f U.S. Often nest near build i n gs. I nvade houses. Stings are painful.
B LACK CARPENTER ANTS exca vate galleries and nest i n wood. They enter houses to get sweets. Bite but d o not sti n g .
TERMI TES a re prim itive social i nsects, more closely re
lated to cockroaches (p. 28) than to a nts (p. 2 5 ) . A colony consists of n u m erous whitish, wing less, b lind
workers; a lesser n u m ber o f soldiers, with l a rge brown ish heads equipped with powerful jaws or with a bellows sha ped snout that expels a sticky or odorous fl u i d ; a n d
reproductives, the king a n d q u e e n . Ad d itional winged m a les a n d fe m a les are produced for swa rming, which ta kes p lace in spring or after rains in warm weather. After a short flight they brea k off their wings and mate. Each m ated pair then crawls off in search of a suita b l e place t o esta b l ish a n e w colony.
More than 50 species of term ites occur in t h e U . S .
Th eir spread as fa r north as Mi n n esota i n recen t years is attributed to increased use of central heating in b u i l d ings, e n a b l i n g them t o survive winters . Nea rly a l l U . S . species l ive i n the soi l ; m a ny o f the more than 2,000 species of the tropics build aboveg rou n d n ests .
Term ites eat wood but can not absorb it until the cel lu lose is converted i nto soluble s u bstances by proto zoans that live in the termite's digestive tract. Neither animal is able to s u rvive alone.
S U B T ER R A N EA N T E R M I T ES
l ive i n col o n i es i n soil, a n d workers travel through t u n n e l s or m u d t u b e s to the wood a bove. Fungi that grow i n moist, dark tunnels ore eaten by termites, supplying protei n and vita m i ns. Swa r m i n g fl i g hts or m u d tubes up a foundation ore evidence of a termite i nfestation. I n late stages, floors sag as eaten-out bea m s cru m ble.
To contro l , no wood of a build ing should touch soi l . Preventive measures should be to ken as a b u i l d i n g is being constructed. Place m etal s h ields between the fou ndation and sills and al low air to circulate u nder buildi ngs_ Beca use of the special equip ment needed, use a professional pest-control operator, especially in treating a b u i l d i n g a l ready erected . He w i l l force penetrat i n g i n secti cide i nto the wood or foundation, Treat the soil be neath b u i l d i ngs, or use a f u m i g a n t . I nspect regularly to detect renewed activity.
worker
0.2 i n .
reproductive
0.5 in_
DRYWOOD TERMITES o re prev alent i n the southwestern U.S. No contact with soil is necessary. Often they i nvade a house at roof l evel and may i nfest furn i ture or books. Piles of brown ish, see d l i ke excrement pellets pushed from tunnels ore s i g n s of their presence. Preventing en try is not economical. Contro l , w h i c h s h o u l d be done only b y experts, consists of forcing i n secticide into tun nels. Poison i s spread as workers g room each other. House o r i nfested object moy be f u m igated, but this does not prevent rei nfestotion.
GERMAN COCKROACHU
0.5 in.
COC KROACHES feed on a great variety of foods
meats, c heeses, sweets, and starches, including the sta rch in c loth ing or in the g l u e of book bindings a n d stam ps: When very abunda nt, they m ay a lso eat h u m a n h a i r, skin, and nails. Cockroaches secrete a stic ky, odorous fluid that may be left on foods or m ate ria ls. Fortun ately, cockroaches appear to be o n ly incidental ca rriers of diseases.
Most of the more than 3,000 species of coc kroaches l ive i n the tropics or subtropics. About 5 5, occur i n the U . S . ; only four species are common household pests .
Norm a l ly cockroaches are active o n ly at nig ht. They d evelop by a g radual meta morphosis-egg, nymph, a n d a d u lt. Egg cases conta i n two rows of eggs, and the nym p h s escape through a seam along the side. Nym phs look like adults but l a c k wings a n d may be a lighter color. After a period of growth and several molts they become adults. The time required for them to m ature varies with the species a n d a lso with the season and the region . Temperature a n d moisture as well as food are i m porta nt factors i n their development.
The best permanent control for cockroaches is elim i n ati n g accessibility of foods which th ey eat.
GERMAN COCKROACHES, or Croton Bugs, ore common i n U . S . , e s p e c i a l l y i n n o r t h e r n stoles. Dork stri pes on shield b e h i n d h e o d ore d isti n g u i s h i n g . Both s e x e s wi nged o n d active. German Cockroaches com mon· ly enter houses in bags or boxes from grocery stores. They tend to cluster i n warm, moist places, os arou nd hot-water p i pes, and stay hidden when not feed ing. Females carry the egg cap sule, conta i n i n g 24 to 48 eggs, until hatc h i n g time. Nymphs may e m erge while the capsu le i s sti l l attached to t h e female.
I n most areas German Cock· roaches ore resistant to D DT, ch lordane, ond other ch lori nated hyd rocarbons. They can be con trolled with organo-phosphates, such os m a lathion.
B R O W N - B A N D E D C O C K ROACH has two l i g h t bonds across the bose of its wings. U n l i ke other cockroaches, it i s as co m m o n i n the bedroom as in the kitchen, req u i r i n g warmth but not a s m u c h moisture. Control is difficult because these cock roaches are found so widely through the house. The m ost effective woy to reach them is with f u m iga nts, keeping room or house closed for several hours.
O R I E N T A L COC K R O A C H ES,
also called Block Beetles or Wa ter Bugs, are most sluggish of do mestic cockroaches. Females have s hort useless wings a n d are slig htly larger than m a les. Cam manly i n fest damp base m e n ts. C o n t a c t - i n s e c t i c i d e b a r r i e r arou n d a foundation blocks en try of these cockroaches and other crawl i n g pests.
A M E R I C A N C O CK R O A C H ES
are the largest cockroaches i n t h e U.S. Bot h sexes a r e w i n g ed , their fl ig h t g l i d i ng a n d fl uttery. The female deposits her egg capsule soon after it forms, someti mes gluing i t to a surface. In the South these cockroaches ore com m o n outdoors, wh ere they l ive u n d e r bark or i n vege tation. They can be control led with contact i n secticides or l u red to poison baits.
CLOTH ES MOTH larvae feed on woolen fabrics, feath ers, fur, mohair, and other animal products such as d ried m i l k a n d meals. The adult moths, com m o n ly cal led " m illers, " d o not eat, a n d u n l ike most other moths, a re not attracted to lig hts .
Materia l li kely to be attac ked should be cleaned a n d exposed freq uently t o light. Brush i n g clothes dislodges the eggs a n d l a rvae. Storage of furs at a tem perature of 45 degrees or cooler prevents d evelopment of moths or will k i l l them if the temperatu re is raised a n d lowered several ti mes during the storage period . Items can be sp rayed with resi d u a l contact insecticides or wa s h a b les rinsed in an i nsecticide sol utio n . Th ese treatments kill the insects as they fee d . Mild fu migants such as para dichlorobenzene crysta ls or naphthalene fla kes d iscour age moth atta cks. These insecticides wil l also k i l l moths a l ready i n the fabrics but a re effective only when used in tig ht conta i ners or closets . An infestation may persist and spread from l a rvae that feed and deve lop on lint in cracks i n the floor, beneath baseboards, or in vents. In heavy i nfestations a n entire house may be fumigated . This should be done only by a professional exterminator. DERMESTI D BEETLES a re pests of fabrics and u p holstered furniture a n d also infest cured meats, meals, ch eeses, h i des, h a i r, flour or other grain prod ucts, a n d spices . Th ey a r e serious pests in museums. Outdoors they are va l u a b l e as scavengers . La rvae of derm estid beetles are more a ctive than the larvae of clothes moth s . Ad u lts fly in dayti m e . Th ey com m only feed on the pollen of flowers a n d a lso breed outd oors . Treatments effective for clothes moths also control carpet beetles. In both cases, good housekeeping to el i m i n ate breed i n g pl aces is the most i m portant preventive .
WEBB I N G CLOTHES MOTHS
are com mon fabric pests that oc cur throug hout the world. Fe males lay eggs about 0.02 of an inch long (barely visible), either singly or i n s m a l l groups, stick ing them to the th reads of fab rics. Eggs hatch i n a few days to several weeks, depending on tem perature and h u m i d i ty. The larvae are so tiny they can crawl between the woven threads of fabrics. They s p i n a s i l ky web bing o r tunnel as they feed, someti mes moving to another spot if their food runs short. Damage is m ost common under col lars, i n cuffs, or i n other dark areas of garments. Full g rown larvae spin a s i l ken co coon from w h i c h they e m erge as adu lts in t h ree to six wee ks. CASEMAKING CLOTHES MOTH larvae s p i n a case of si l k and fabric, carrying it with them as they feed. The case spl its a n d the " V " of t h e s p l i t i s fi l led i n as the larva g rows. C o m m o n i n n o r t h e r n s t a t e s . P l a s t e r B a g worm s o f southern slates build a portable case of bits of plaster or fabric woven i nto the s i l k of the case.
CARPET BEETLES, a l so called Buffalo Beetles, are derm estids that i nfest woo l e n fabrics, feath ers, and other a n i m a l prod ucts. Related pests i n c l u d e the larger Hide Beetle and the larder Bee tle. Hides and s k i n s a re treated with arse n i c powders or s i m i l a r stomach poisons. Cheese, cured meats, a n d other fatty foods should be kept in tight con tainers ar u n d e r refrigeration.
wingspread
eggs, larvae ana cocoons o n fabric.
CASEMA K I N G CLOTHES MOTH
1. LARDER BEETLE, 0.3 in.; 2. CARPET BEETLE, 0.2 i n . ; 3. H I D E BEETLE, 0.3 i n .
House Fly can eat only l iq u i ds. It sal ivates on solids to di ssolve them, then sponges u p liquid.
pu pariu m
3-10 days
HOUSE FLIES are bothersome, d a ngerous pests, trans m ittin g d iseases and parasites from the filth i n which they breed to the foods m a n eats. Females may lay h a lf a d ozen or m ore cl usters of 1 00 to 1 5 0 eggs in a sea son. In favorable cond itions a life cycle is comp leted in a bout two weeks but m ay take m a ny months in cold weather. Wi nter is ord i n a rily passed i n the larva or pupa stage, but a d u lts may overwi nter in warm nic hes. Dis posal of g arbage, m a n ure, sewage, a n d s i m i l a r d ecay ing or fermenting wastes in which the flies breed and the mag gots develop is most im porta nt. Win dows a n d doors should be fitted with t i g h t scree n s . F l ies t h at enter can be killed with aerosol sprays . Wa l ls, sil ls, a n d screens can be treated with resid ual surface sprays. As flies in most areas are resistant to D DT, othe r contact i nsecticides m ust be substituted. Poison baits ( m i xtu res of syrup- or suga r-water with an insecticide) are effec tive in places that can not be scree ned or where sprays can not be used because of danger of conta m i natio n . 32 HOUSEHOLD PESTS
LITTLE HOUSE FLIES are smaller and more slender than the Hause Fly. They h over or fly back and forth without settling on food. The s i m i lar, closely related La trine Fly breeds i n h u m a n ex crement. Maggots of both have a flattened, s p i n y body.
B L O W F L I E S a r e l a r g e a n d noisy. Most species are meta l l i c blue or green, l i ke the Green Bottle and Blue Bottle flies shown here. The g ray Cluster Fly, s i m i l a r i n appeara n ce t o House Fly, is a blow fly com mon in houses. Blow fly mag gots develop i n garbage or carrion.
MOTH FLIES, their wings a n d body covered w i t h hair, often a p pear i n s i n k or bathtub drai ns. The m aggots develop i n the gelatinous sludge i n the bends of pipes. Sometimes large n u m bers i n v a d e f r o m outdoors, where they develop i n garbage or sewage. They are so tiny they can crawl through screens.
F RUIT FLIES can enter houses
through ord i nary screens. They are attracted to rotting or fer menting fruits or liquids. A com p lete l ife cycle req u i res less than two weeks. Other com m on names for them are Vi negar Flies or Pomace Flies.
DROSOPH I L A FRUIT
BLU E B OTTLE FLY 0.5 in.
CLUSTER FLY
0.3 in.
GNAT i s a name used for m a n y k i n d s o f s m a l l fl ies, most of which are o n l y nuisances. The Eye Gnat, attracted to eye secre tions, tra n s m its pin keye. These persistent tormentors are most active i n early morn i n g or eve ning hours.
MANY OTH ER KINDS of insects, as well as spid ers, and their kin e nter houses, where they a re either n u i sa nces or potentia l ly d a ngerous pests. Some of these a re d iscussed i n the section o n i nsects that bite or sting ( p . 3 8 ), others i n the section on stored prod u cts ( p . 1 4 6). Often an i nvasion of i nsects is o n ly tempora ry, as when they a re a ttracted to lights. When a lawn is mowed, a vaca nt lot is cleaned up, or a crop is h a rvested nea rby, i n sects disturbed from their normal livi n g places m ay be temporary pests . Others are reg u l a r visitors a n d com panions i n dwellings.
34 HOUSEHOLD PESTS
S I LVERFISH are scaly, w i n g l ess insects that p refer foods with a h i g h starch or sugar content. They eat the glue i n book b i n d ings or f r o m wal l paper and often damage pai ntings or paper. Sil verfish prefer cool, d a m p places; the closely related Firebrat l ives in war m , drier spots. Res idual sprays ar d u sts are effective i n keeping down infestations. E A R W I G S are e a s i l y r e c o g n i zed b y forceps ot e n d o f ab domen. Someti mes occur i n large n u m bers in hou ses. They can bite and also p i n c h , but seldom break the s k i n . They hide during the day, feed at n ig ht. Use resid ual sprays o r d u sts.
HOUSE CRICKETS sing o n the hearth or wherever they can find warm th. When cold, they are sluggish and q u iet. Field Crickets a l so enter houses i n autu m n . As house pests, cric kets eat o variety of foods and may be destructive to clothes. Household sprays, d u s t s , a n d p o i s o n b a i t s a r e usually effective.
WOOD-BORING BEETLES of o
n u m ber of species may infest wood used in houses or furni ture. larvae of the Southern lyctus Beetle reduce wood to a fine powder, which is pushed o u t s i d e t h r o u g h s m a l l h o l e s . D ro p p i n g s o f t h e F u r n i t u r e Beetle a n d others a r e round pel lets. As some kinds feed, a tick ing noise in the wood can be heard. F u m i gation by a q u a l ified pest-control operator i s the best control.
BOOKLICE, or Psocids, some times beca m e abundant i n stored furn iture, books, or papers, par ticularly if d a m p . They feed mainly on molds but also eat cereals. Booklice are so s m a l l t h a t it is difficult to k e e p t h e m o u t af a h o u s e . Use contact sprays or d u sts.
BOXELDER BUGS d o not b ite, sti ng, or carry diseases, but ore a nnoyances when large n u m bers occur near or in houses. Can be killed with household sprays.
CRANE FLIES look l i k e Iorge mosqu itoes but are harm less. Their larvae, or maggots, some times called leatherjac kets, de velop i n damp vegetation or in the soil. Adults com monly are attracted to the l i g hts i n houses. They can be k i l l ed with house hold fly sprays.
SPRINGTA I L$ often congregate i n cellars o r i n bathroom s or k i t c h e n s , w h erever t h e re is dam pness. They are harm less and can be k i l led with household sprays or d u sts.
SOUTHERN LYCTUS BEETLE
0.1
HOUSE CENTIPEDE
1 .0-1 .5 i n .
CENTIPEDES a r e flat-bodied, with long antennae and one pair of legs an nearly every tru n k seg m ent. The House Cen t i pede feeds on ants, fl ies, cock roaches, and other pests, hence i s beneficial. Its bite, though rare, is painful. Use residual con loci i n secticides or treat joists, s u bflaors, and cracks with creo sote or ather repellents.
MILLIPEDES are a l m ost cyl i n drical, w i t h two p a i r s of short legs per apparent body seg ment, a n d s hort antennae. They move slowly. These features dis tinguish them from swift-crawl ing centipedes. Normally m i l l i pedes a r e fou nd only outdoors, feed ing o n decayi ng vegetation , but they may i n vade houses after rai n s or to escape cold in fall. P I L L B U G S A N D S O W B U G S are land-dwe l l i ng crustaceans. They can survive only in d a m p places, a s i n leaf mold or in base ments. They feed m a i n ly on decayi ng vegetat ion but also eat tender roots of plants. Con trols: clea n u p of debris i n which they th rive; contact i n secticides; poison baits i n h eavy i n festa tions, as i n greenhouses. SCORPI ONS are spider rela tives found o n ly i n warm cli mates. Two species i n south western U.S. a re h i g h ly poison ous. Scorpions are nocturnal and feed m a i n ly o n i nsects, which they catch in their p incers, then paralyze or k i l l with their sting. E l i m i nate debris close to build ings and use contact insecticides that have residual action.
body 0.2 i n .
2-3 i n . across l e g s
DADDYLONGLEGS, or Harvest men, rese m b l e spiders but hove a d i stinctly s e g m ented abdomen a n d sti n k glands. They lack s i l k g lands. T h e i r l o n g stiltlike legs are easily s h e d when the a n i m a l is touched. Daddylonglegs a r e harmless, fee d i n g m a i n l y o n dead in sects. They w i l l k i l l a n d e a t s m a l l i nsects, however, a n d m a y feed on fru its or vegetables.
J U M P I N G S P I D E R S of severa l species often enter houses. They do not make webs. I n stead they hunt actively for prey, search· i n g over cei l i n gs, walls, sills, and fl oors. They can jump quickly, and freq uently use their s i l k as a payout l i n e to let themselves down from h i g h levels. These lines may be a n u i sance, but the spiders are h elpful.
B LA C K W I DOW S P I D E R S are widely d i stributed a n d rather abundant. Their bites are pain ful and may cause death. A doc tor should be called i m med iately to give treat ment. Fortu nately, Black Widows are shy and do not bite without great provoca tion. They usually build their webs in o r beneath objects close Ia the grou n d .
H O U S E SPIDER 0.3 i n .
HOUSE SPIDERS bother house wives because of their webs. Their bites m ay be very poison ous. House S p i ders p rey o n the House Fly a n d other i nsects. Their webs are usually built in corners, w h e re they col l ect d u s t a s well as prey. T h e s e and other spiders can be k i lled with con tact s p rays o r d usts; residual i n secticides prevent reinfestation.
3 8
I N S E C T S T H B E 0 5 N G
Biting flies fee d on the blood of their victi ms. They cut or sta b through the skin with their k n ife-sh a rp piercing mouthparts, then lap up blood that flows from the wou n d . Th ey m ay also b e carriers of diseases.
Insects that sting usually do so as a defense when d isturbed or a n noyed. Sti ngs of bees or wasps may be extremely painful and also d a n gerous. I n the U n ited States more deaths result from insect sti ngs than from the bites of poisonous s n a kes. Med ical knowledge about the effect of i nsect venoms and h ow to treat stings is sti l l l i m ited . Usually there is swelling and i n m a ny cases a throbbing ache that m ay last for several d ays . Sti ngs vary i n severity with the species of insect a n d also with the amount of poison i njected . A sting i n an a rm or a leg is less d a n g erous than a sti ng i n the neck, where the poison may pa ralyze the vocal cords or h a m per breath i n g . The effect of a sti ng also varies with i n d ividuals a n d with their physiological cond ition . Beekeepers com monly build u p a n i m m u n ity to sti ngs.
HORSE FLIES, active only i n the dayt i m e, are m a i n ly pests of l i vestock (p. 56) but may a lso bite people. The bite, only from females, is very painful. Females lay egg masses on leaves, stems, or rocks . . O n hatc h i ng, larvae
BLACK HORSE 0.8-1.0 i n .
d r o p to g r o u n d and complete develop ment in d a m p soi l or i n water. Maggots m a y overwi nter in mud, pu pate i n early spring, a n d em erge as adults a few weeks later. Equally pestering are closely related Deer F l ies.
DEER FL 0.4 in.
BLACK FLI ES, also called Buf falo Gnats, are most abundant in late spring and s u m m e r i n wooded reg ions of Canada a n d t h e U . S . T h e s e h u m p backed bloodsuckers (on ly the females bite, causing a persistent irrita tion) crawl an noyingly i nto the eyes, ears, a n d nostrils. Females fasten their egg masses Ia rocks or vegetation in strea ms, in which the larvae develop and spin cocoons. A l i fe cycl e i s com pleted i n about six weeks. Re pell ents are effective.
STABLE FLIES, l i k e Horse Flies, are principally pests af livestock but may at times bother people. They occur most abundantly in lowlands a n d seashore areas, beco m i n g especially aggressive when the barometer is falling. Both sexes bite. Their mouth parts are sharp a n d stiletto-l i ke rather than spong ing, as in House Fl ies. I n cool areas, they overwinter as larvae or pu pae; in war m e r c l i m ates, active the year around. In h ouses, can be k i l led with sprays. E l i m i nate breed ing p laces ( m a n ure or de cayi ng orga nic m atter).
SAND FLY
SAND FLIES, or No-See- U m s, are tiny bloodsucking fl ies, so s m a l l they ca n go throug h or d i nory screens. They are most a c t i v e in e v e n i ng or e a r l y morning hours, a n d their bites are extre mely painful. Screens and areas arou n d l ights can be sprayed or pai nted with an o i l e m ulsion contact i n secticide. Re pelle nts will keep the flies off i n dayti me. T h e m aggots develop i n m oist vegetation or i n pools (so m e species i n soli water, others in fresh).
House Fly abdomen
MOSQUITOES total more than 2,500 species. Many a re carriers of diseases ( m a la ria, yellow fever, d e n g ue, and fi l ariasis). Others, as a n noyances, cause costly losses of m a n-hours to outdoor workers or reduce the p leasure of being outdoors.
Adult fe m ales lay their eggs on or near the s u rface of perm anent pools or in moist or te m porarily flooded locations. Some species lay their eggs sing ly; others deposit them in " rafts" of as many as several h u n d red. I n most species the fem ale m ust h ave a meal of blood before she can prod uce eggs. Males are nectar feed ers a n d do n ot bite. The larvae, a lso called "wigg l ers, " swi m or rest just beneath the surface. They feed on microscopic organic matter. Development may be com pl eted in as short a time as five days or m ay req uire several months; the average is a week to 1 0 d ays. Then the l a rvae tra nsform into pu pae, also k n own as "tum blers" because they continue to be active. The adults emerge i n from two days to two weeks or lon ger, depending o n the species and the water cond itions. Adu lts l ive for a few days to several months, a n d most species do n ot travel more than a m i l e . Some hibernate in the adult stage.
Large-scale mosq uito control consists of e l i m i n ating breeding a reas by d ra i nage, sprea d i n g oil films over the surface of the water, using i nsecticides to destroy the la rvae or pupae, or sp rayi n g with contact insec ticides to k i l l th e adults. All of these controls m ay a lso destroy h a b itats or kill fish, bi rds, or other va l u a b l e wild life a n d should be undertaken only after ca reful study by profession a l ly trained peop le. Aro u n d h ouses, get rid of breed i n g places, such as ditches, l ow spots where water stands i n lawns, or conta i n ers . Screen i n g wi l l k e e p a d ults o u t o f houses.
eggs laid singly
C O M M O N M A LA R I A M O S QU ITO and the Western Ma laria Mosqu ito, known to m i g rate 25 m i les in spring fl i g hts, trans mit malaria i n N.A.
SALT- M A R S H MOSQ U I T O E S breed i n large n u m bers along Atlantic a n d Gulf coasts. A re lated black species occurs i n South, others i n West. SALT-MARSH MOSQUITO
eggs laid singly
Y E LLOW - F E V E R M O S Q U I TO, found m a i n ly in port a reas i n South, i s recog n ized b y s i lvery stripes. U n l i ke most mosquitoes, it bites during day.
HOUSE MOSQU ITO, worldwide
i n d istri bution, beco mes active a n d bites at night. Mem bers of this genus carry the virus caus ing encep h a l itis.
HOUSE MOSQUITO
