AN ESTIMATE OF THE DAMAGE BY SOME OF THE MORE IMPORTANT
INSECT PESTS IN THE UNITED STATES
STATE PLANT BOARD
J. A. Hyslop
In Charge of Insect Pest Survey
Bureau of Entomology
U. S. Department of Agriculture
f. .I .f <^ ^/f ^ tf i '/ ..^ .- 1'.i,'
December 31, 1930
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Digitized by the Internet Archive
AN ESTIMATE OF THE EA'JL&E BY SOME OF TH73 MORE IUPORTAYT
INSECT PESTS III TIE 'JNITFD STATES.
J. A. Hvslop
In Chiarge of Insect Pest Survey
Bureau of Entomology
U. S. Departanent of Agriculture
In the year 1925, and again in 1927, a study in cooperation with
the State workers was made to determine, if possible, our more important
insect pests. The res.ilts of thesa studies indicated clearly that the
judgment of entomologists as to the re'attve importance cf different
insects was decidedly biased by the work that they had- ir.mediately under
Estimates on the damage done by insects are numerous. The most
comprehensive of these* have served a:; % standard since that time. The
difficulty encountered in arriving at anj degree of accurac- ha.s hampered
this type of endeavor. --
It is quite necessary, however, that we have at least a generalized
conception of the economic statv.s of our several pests. The control of
insects involves the ex;:penditure of money, and unless we have figures
regarding the monetary loss caused by them, we can get no definite idea
as to the benefits in terms of dollars derived from control measures.
With such figures, we have only to subtract the cost cf control
from the estimated loss to learn wl-ether or not, in a particular case, our
methods of control are worth while. In the case of pests of long standing,
and on which repressi'.e measures "iave been usEd for many years, only the
estimated loses in cases where control lihas been nelccted will .ive a-i
idea of the saving effected. To zinjle there casas out over a lre- area
would be a difficult task, and the "loss estimates" usally do not mak
This monetary, loss is affected by ma:vny factors thP.t tr9:1 to rj-acc
the accuracy of the estiz-atcs. For instance, suprl,- an' .r ix f.: :',
and the reduction of a crop by an insect pest nuttr'.-.itic: 11 r-". ,': z '- L'ce
if the price of that crop is not fixed by a -'oild r-h'et. Th ra is a ,-,
cies.d fallaty, tharcfors, in trying to ezt!i..,at t-.Ce oraoiy returns t. t
irlatt, C. I., The aw-al loss occasion,.d by lkesrt-ct ro Intaects in the
United Stattes. U. S. Dept. Asgr., Yearbook for 19'4,
p. 461-474. 1905.
Marlatt, C. L., Losses d'.e to insscts. Part I. Insects as a che(.W- r.
agricultural production .nd as a -ource of waste t .2-
cumulated supplies. :Tational Conuzer---ation Cor..si3.ljn
Rept., vol. C, p. 301-30?. 1909.
would have been received for the crop had the insect been completely
controlled. If such an estimate is based on the price of the redauod crop,
it may be entirely erroneous, and in any,- case there is no way of making it
accurate, for we do not know what the price would Ihave been. Climatic
conditions also materially affect crop production. The control of one
insect at times interferes with the control of another. But despite these
many interferin, factors, the estimates indicate, in a broad general way,
the relative importance of the pests concerned.
The insects treated in this paper arce but a small fraction of the
total number that are economically affecting our existence. In the files
of the Insect Pest Survey there are now recorded 6,000 species of insects
that have been reported as of more or lesr economic importance in the
United States, so the total loss of $924,C40,000 occasioned by 34 of our
more important pests (Table I) indicates that a previous estimate" '"
of over $2,000,000,000 by all .nsects is extremely conservative.
Many of the more recently introdr.ced pests, such as the European
corn borer, the alfalfa weevil, the oriental fruit moth, and the Japanese
pbeetle, are not included in this estimate because their place in our fauna
is not Zret well enough established to irndicate what daI'age they will
Damarne by the boll weevil (Anthonomus -raiLdis Boh.) has been
estimated by the crop reporters of the Bureau of Agricultural Economics
over the 19-year period 1910 to 1928 at an average annual loss of 12 per
cent of the cotton crop. (Table II.) The average annual cotton production
in the United States for the past three years was 14,000,000 bales, valued
at $1,200,000,000. The workers at the agricu-ltu-.ral experiment stations and
the State departments of agriculture of the Cotton States have estimated
the damage by this insect at an even higher figure. The South Atlantic
States cstimrate the loss at 22 per cent and the lower Mississippi Valley
States at 19 per cent. Accepting the nore conservative estimate of the
lon er period, we find that the 14,000,000-bale crop is only 88 per cent
of the crop of 15, 90C, 0CO bales that mi./ht have been harvested had it
not been for this one insect- a loss occasioned by the boll weevil of
1,900,000 bales valued at $163,000,000, ignoring the depression of cotton
prices that would have been protuccd is this extra cotton come on tho
Mnch of the cotton crop at the present tire is being dusted to
control the boll weevil. A summary of airplane operations, though by no
means complete, indicates that Lhuring one season about a quarter of a
million acres of cotton were dusted in this manner, and the acreage dusted
by -ro'Lnd machinery is much larger. On account of the very large part of
the cotton crop that is not dusted annually, or is dusted only once, the
general avraie rarely exceeds tv;o treatments per year. Average dusting
costs only $2 per acre, and this can be added to the damage occasioned by
this insect. Of thu 44,000,000 acres devoted to this crop, about 750,000
acres were dusted in 1929 at a cost of $1,500,000.
BOII WCor 03O COR'T 3AR WOc:' (..ei ot'--.s obsoiet ?-ob.)
The crop reporters of the BTureau of !!ar-.'ets h.ave estimated that
over a 19--ear eerioe, )I'l0-IO3, i-isects other than the boll weevil
destroy-ed 4 oer cent of the cotton crop. Quai.'tance and Braes (3ur.
Ent. Bul. 50, 1`03) estimated the apnroxi.,ate annr-2l loss to the
cotton crop b-- the boll wornr in Teyas, Louisiana, Mississippi, Oklahoma,
and Arkansas, the States in which boll worm injur" to cotton was most
severe, as 4 )er cent, ani observed from 8 to 60 per cent loss to cotton
b- the boll worm in Texas in 1903 and 1204. B. 3. Coad. believ.-s that
$a&'aTe by miscellaneous cotton insects ot---er than the boll weevil and
the boll worm amounts to at least 2 per c:nt. This woulL leave 2 per
cent of the dar.iago attributable to the boll worm. That is, the 14,000,
000-bale crop is but 98 per cenit of the crop to be expected without
the boll worm ani the loss would amnount to over 280,000 bales or a
monetar2- loss of $24,000,000.
Heliothis obsolet, Fab. is known as the corn ear worm when it
attac'-s corn. In the far South, srr-.et corn is not rencrally -rorn on
account of the boll n:or-a. In a central belt, includi-v-. Delaware and
Maryland, and westward to Illinois, front 10 to 50 per cent of the crop
is destroyed by this ine'e:t and often the infestations are so severe
that the e.-tirecannin- crop is rejected at the can. series. In 1900,
Quaintance and Bir.es (Bur. Ent. Bul. 50, 1905). estimated that 25 per
cent of the s.rcet corn was inji,.rod in the ca-i:ery sections alone.
The 927-K29 corn pac': averaw.e-l 14,000,000 cases of 24 cans each
pe'r year, about 7,000,000 of which -ere from the boll-worm belt. If
this is only 75 per cent of the potential4 crop that would have been
raised but for the insect in this area, the da-nmace was over 2,000,000
cases; the mo-icy loss is, rou1-.lr $4,00, 000, besides loss to sweet
corn marketed in the ear.
The damage to field corn, though less sve:'-e tha-. to sweet corn,
an.iounts in the ag-re-ate to a mach larger fir're. The sa.m. investigators
(Quaintance ana' 3ruae, loc. cit.) found that individual larvae fed in
the laborator-' coz-ix.ed 40 ':e-r..els of corn each during their period of
growth. Allon"inr ?00 'Oernc]s to th3 avera-c ear, this would mean a
loss of 4.5 per cert.
Corn-ear-v'orm investigations carried on in l7ebras"-a by Swcn'-
inc'.icated that in 1908 certain fields were 100 per cent infested a&-
pra.ctically 50 per cent of the -rrai: was act-iall, coxZ'.r3jd. ULs' el-
in this State, however, infestations run bett-,een 40 and 75 infcst:d
ears per 100, ani the total 'rain consunred was approximately 4 pcr
cent of all cars.
Intensive studn' carried on by Dean and EcColloch in Tansss for
twenty, voa.ri indicates that the annual percentage of cars infested is
anproximately, 75 per ce.Lt and rarely drops below 50 per cent, and
counts of the kernels o' sevsral1 thorsavd ears indicate that the corn
actually consumed amounted to 4 per cent o: th.e :cr-nels on the infested
The State and station wor'-ers in the Corn Belt have estimated
the dam-re b- this ins-:ct as increasing very mr.terially from the North
southward. The Irid.le Atlantic States estimate 5 per cent; the South
Atlantic, 4 per cent (the writer believes, ho:-ever, that this is a
ver- inaccurate estimate and far below the actual da" age in this region);
the East Central States, 8 per cent; the West Central States, 5 per cent;
and the lower Mississippi Valle:,, 10 per cent. This would give an
average d.-'a.-e over the entire Corn Belt of over 6 per cent.
Adoptin- the more conservative estimate of loss, based on extensive
field investigations, of 4 per cent, oar corn crop, based on the 3-"-oar
average, 1927-1929, of 2,700,000,000 bushels per annum, would be only
96 per cent of that which mioht have been obtained were it not for this
one insect, or 2,800,000,000 bushels, .ia:-I:-.,r: a loss of 100,000,000 bushels.
Placing the value at the 3--ear averse for 1927-1929, 75.2 cents p:r
bushel, the monetary loss would be *75,200,000.
Tomatoes over the greater port of the Southern States Rrc seriously
attached by this insect. Quaint..nce and Brues ( 0'p. Cit.,) esti-.te the
dana7-e to tomato fruit at 2 per cent. The tomato crop of the United States
for the 2- ye-.r period, 1?28-1929, averaged 1,520,000 to.nis per year Ind was
valued at t46,000,000. Althou-h this insect is not a serious tomato pest
over t.'e entire tomato-growing- area, about half of the tomato acreage in
the Units'l States, located in that strip of territory extending fro.i
Texas across the southern part of the United States to Maryl.aind, is
serioumsI7 infe-.tsE. Two per cent of half of the total tonnage would
amount to 16,200 tons or a monetary loss of $460,000. Totaling the
losses occasioned by this insect, we have:
Field corn............ $ 75,200,000
Cotton ............... 24, 000C 000
Swcet corn ........... 4,000,000
Tom-toes .... ....... 460,000
Total .............. $103,660,000.
McColloch and Dea: carried on vc;ry e-tonsivc investigations of the
Heosian fly (Ph',t:-pha:-a de strictor Say) in Kansas from the years 1923-1927
in which field observations gave the following results:
The dawrage for- Auounted to
1924 20, 000,000
1925 40, 0,0, 000
1927 20, 000,000
This amounts to Hos-ian fly .amu'rve of approxiir.Itcly 15 per cent of the
crop usually harvested in that State.
The experiment stations anc' the State cnto51Olo"istc of the ,.Ast
Central States have estimated thc an'r-,.l loss occrisioi c-1 b, this insect
at 13 per ceit; and the 'vor:kers in th- !TdUle Atlantic States at 6 per
cent. The winter wh:-eat crop of Michi-an, Wisconsin, Misvouri, Iowa, and
Kentucky mnay te included in considuri.:, thit of the PAst Central States,
because prodl~cod under similar conditions. If the loss for each region
is estimated on the bisis o:f its 1920-1928 winter wheat crops and thu
.cbove percentages, tho threat reiiens will shove a tot-al annual loss of
43,000,000 bushels, which, valued ?.t $1 per bushel, would amount to a
monetary loss o0 $48,000,COO. C. L. lf:tcalf, in the 55th Annual Report
of Entomolo~ic-l Society of Ontario, Lives almost three times this
figure as the loss occasioned by ill insects attacking wheat.
Reviewing the situation of the chir.ch bug (Flissus IcucoLqptcrus Say)
during the last 50 years, it is fouTnd that the average number of counties
yearly repo.-te1 as infested in Kansas, if distributed evenly over the
entire period, would amnornt to 25 per cent of the entire number; in
Missouri, the data arc much less satisfactory and wve have an avera,e of
9 per cant annually; in Illinois 18 per cent, end six per cent in Irdia -a,
and an average over the entire territory of about 14 per cent infested
annually to the extent of causing complaint. This belt produces about
$550,000,000 worth of corn and $225,000,000 worth of wheat (estimates
for 1927-1929). In the iniestcd territory, wheat is often severely
injured by this insect during the outbreak- years; and corn, in fields
where the insect is not checked by control practices, is sometimes a.
The value of 14 per cent of thn wheat in this territory is over
$30,000,000 per -ear at prevailin.o prices from 1?27 to 1929; 14 per cent
of the corn crop would amount to $77,000,000 at 193C corn prices. With
an estimate of 50 per cent loss dur.n,- outbreaks, th'ie avere.e annual
loss occasioned ,,by,, this insect -.oulI be over $50,000,000. While loss
does not always reach 50 per cent, it som-ti!nes exceeds it; the chinch
bug causes somc loss in counties not reported as infested and in other
States; $50,000,000, therefore, seems a fair estim-ate.
The sugarcare borer (Diatraea sa.ch?2ralis Fab.) is undoubtedly
the most important pest to sugarcane in this country. Messrs. rolloway
and Haley estimate that the damage to sugarcane due to this insect ovcr
a series of -oars amounts to approximately 19 per c*bt. Gon.varted into
sum4r, this wants aRpxoxiat.ely, to a Ions of 58,000 totw. At a Twrice
of far cents per pound, this reaches $4,340,000. No account is taken
of the loss to cane used for sirup, nor to seed pieces of surwrcane.
Apple aphids are estimated by the entomologists of the States east
of the Mississippi River as reucin,: the apple crop 13 per cent; it seems
li'-.el," hat this estimate applies to outbreak years, and for all years we
ma:- "Luce it to 6 p.?r cent. The apple crop in this region averages
around 85,000,000 bu:htF`s annually (1927-1923). This is only 94 per cent
of what might o,.vc been harvested '7ere it not for these insects, and
indicates a crop loss of 5,000,000 bushels with a valuation of nearly
$7,000,000. To this nmast be adied the cost of spraying to prevent a much
hi -hL.r percentage of injury over this entire territory. In this re.Tion
there are 65,000,000 bearing trees. About 30,000,000 of this number are
in commercial orchards, and are zpr.ve"K with nicotine sulphate when
necessary, or apioroiime.-el.. once in three years at an average cost of 12
cents p'.r tree; the i.nou:t lost in e:-pknd.itures v'oul/be 1, 200,000.
The codliln7 moth (Parpocapsa pomnonella L. ) hoas been very carefully
studied by r.-any investigators in this country. A long series of experiments
carried on by Quaintanco and Scott in Virginia, I)el.w.are, Michigan, Kansas,
and. Ar<.rnsas and expriments carried on by Gossard in Ohio, Rumney in West
Vi-~i-, Tell I
Viri.ni:., pelt in Neow Yor": State, and Jonis and Davidson in California
indicate tlhat the proportion of unsprWaed fruit which wvas found to be
infested by this insect ran from 15 to 74 per cent with an average for all
experiments over the entire npriod.of 45.13 per cent. For the triennium
1927-1929, the American apple crop avbr.ned about 150,000,000 bushels of
apples annuall.-, valued at over $180,000,000. Culls and wormy apples are
rarely :-orth more than 50 ocrints per bushel. Were it not for spring we
could possibly count on an -ver-.e of 37,500,000 b-shels that would have
to be soid. at a very considerable c'iscount. Estimates received from the
State entomologists and the State agricultural experiment station workers
throughout thr anple-growing States indicate that, even including those
orchards v.-wich are car7:fully sprayed, the damage runs to approximately
12 per cent of th.e fruit. TIs nould occension a reduction in No. 1
apples of 18,000,000 burheols or a Monetary loss of about $13,500,000. To
this must be acdled the cost of sprai,-!ng "which prevented a nmuch more
considerable lo.-n than indicated b- the figures already given. To spray
an anple tree ovr the se..son., c ':-ing oiIly for arsenica]s eand labor, the
cost is 35 cents. The nu:,ber of t'oeez of -carring age in the United States
in 1-24 was 104,000,000.
In the years 127-1929, the conrmmercial crop ,.'as over half the whole
crop. Allowing fcr a heavier yield in commercial orcla.rds, we may figure
the cormercial trees which are regi.lorly sprayed as at least half of the
total number of trees.
Spraying 50,000,000 trees for the codling moth cos*s, therefore,
$17,50,000O or a total loss occasiomied by this pest of over $30,000,000.
(A ine' expense, icid washing, to remove excess arsenic amounts to 3 cents
In cont -.-ap1i atin those i --',Lirs and compnri1'r' the loss occasioned.
b: this pest and other pests controlled fairly satisfactorily b.
i isecticidal neithods -ie must '.ceo in mind that a pest which potentially
is extremely: serious but .-hich is very e fectively controlled by an
inc;oc-isivo measure '-ill sho-.' a sni'.ller loss than a much loss potu.n-
tially iulportnlt pest that is but poorly controlled or controlled by a
very expensivei method. In some of t.-osc c-sc-z the low fi:-uro indic-.tos
trat ontomolo--icn.l nrctic.e is .nore gc:ILrally effective and not that the
pcst is of minor importance).
The pe?.ch crop of the U:ited States over-.zed,during the three :-ars
1927-1929, 53,000,000 bushels v?.luod at over $62,000,000. On.e of the
most imi)orta.nt limiting, factors over much of the territory is the pcach
borer (Ae-eri.. exitiosa Say). It i". very difficult to got at the actual
d,:?a,-c done b-' this insect -.s it vcr-., quickly kills the trees !.nd re-
duction in crop is hnr-I to me..sure. The use of paradichlorob-nzene, a
very effective control me-su.re, costs from 5 to 6 cents per tree, de-
pending upon the price of labor, .stimr.tin- the cost of labor at ,3 a
dany, thec coF.t of tren.tin- the po-ch trees no', -ro, n in the United States
.vould amiount to $5,900,000. This -'ill give a relative idea of the tax
that this ir-sect cx-.cts from the pe':ch grower but it does not include
the much re-iter loss in tre.s killed. Ho.-.ver, as this is considered
.n e::tremel,- economical treatm-ent, tho loss that the insect would
occasion 'v-er_ it not controlled viould prob:.bly be miny times this figure.
PLU A CURCULIO
The plum ciirc'ilio (Cono trichcl's nenn,_ir Rbst.) has been estimated
by the fruit :ro- ers of the deciduous fr-.it belt east of the Rocik
Mountains a.s causin* an annual loss to the peach crop of approximately
15 per cent. Apples ?.re not .o severely or extensively injured, and re
may reduce this fi-ure to 5 p.:r cent for them. Qa-uintai'ce and Scott,
investigating this insect in Dela-"u-e, Virg'inia, Michi.-an, and Arkansas
over a three-'-c:.r period, l-'Y-lD']l, found that in unsr.rayed check plats
the average infestations ran to 441.5 per ccnc of the fruit. This i".scct
is confined to the region east of the Rocky Mountains, and inasmuch as
the peach crop o- this region is valued on an average at nearly $45,000,
000 (1927-192D), this insect produces a loss of about .3,COO,000 on
peaches. Apples of this region are worth about $126,000,000 and at 5
per cent curculio damnge would be nearly t7,000,000. Some loss is lso
caused to othor fruits. To this 'e rr-ist acl the cost of con.trollin- the
insect. The pinr: application on apoles is lar-'ly for this pest as far
as the arsunical is concerned, so a cost of 5 cer-ts per tree is con-
servative and would amountt to a total cost of $3,000,000 on apple, pe-.ch,
plmn, and pear. Los-es and costs due to ,athis -isewt on Ipplcs and
peaches may I-ell total $17,000,000.
Of course, it would not be correct, in the case of the-.e decidrous-
fr.it insects, to cha r-e the -ntire cost of arsenical spra,,ing to an; one
pest when that spray- is effective for more than one insect or disease.
We have, therefore, prorp.ted the cost of spraying among the insects
that attac'7 the fruit.
S-1 JOS: SCA1U
The Saml Jose scale (Aspidiotus perniciosus Comst.) at one time
threatened the entire deciduous fruit industry of this country. Owing
to the general practice of spraying, it is not today generally con-
sidered a s rcsponnible for avn- very considerable portion of the dan.age
to the commercial fruit crop, although undoubtedly, ow'ing to the lo-.wered
vitality of unsprayed trees, a very considerable crop loss is sustained.
The most tarigible figure on the driagpe by this pest is the cost of
dormant spra'i.ng, so -cner.lly practiced for its control. Practically
41,000,000 deciduous fruit trees are spram:ed in commercial orchards every
dormant season for the control of this post, at a rough cost of 18 cents
per tree, or $7,380,000. Another form of damage occa.sioned by this
insect is the lowered quality of fruit due to spotting.
COLR3OAD0 POTATO BEETLE
The Colorido potato beetle (Leptinotars-. decomlinea.ta Say) is a pest
that during the past 8 or 10 y--rars has occasioned no ver"- considerable
shrinkage in the commercial potato crop, owing, in part, to the highly
effective control measures which are now quite generally in practice.
Despite this fact, ho'-cver, in the New England States it is estimated
that 15 per cent of the crop is annually destroyed. In the Middle
Atlantic and South Atlantic Staites the damage is much less considerable,
but is estimated at 3 and 5 per cent, respectively. In the East Central
States the damage is estimated at approximately 10 per cent. In the
irrigated potato--ro-ing section of the Northwest, the pest is not
generally distributed, and it is not a factor in the early-potato sections
of the South Atlantic States.
The average reductions of the main potato crop due to this insect,
despite the very effective control measures, is probably 8 per cent, that
is to say, tihe 340,000,000 bushels annually harvested in the States where
this ins%)ct is a pest is but 92 pcr cent of the crop that might be
harvested were it not present. This amounts to a loss of about 30,000,000
bushels v-.lued .t '29,000,000. To this unamount must be added the cost of
spraying potator.s r'hich is generally practiced throughout the commercial
potato-growing sections. Charging for the arsenicals and for one-half of
the labor (the other haimlf is cla.r-reoole to fun:ous-disease control), it
costs roughly $1'.:50 per acre to spray potatoes. As the acreage of this
crop in the United States is approximately 3,000,000 and as approximately
one-tenth of this is sprayed, it costs about $450,000 to prevent further
The potato leafhopper (Dnpoasc2 fabae Harr.) and the associated
dise-iso, hopperburn, have been amonq the most serious factors attracting
attention in the potato--ror-in,; sectic'on d".ri.-.. .'he pat few, :'c.rs.
The insect is generally prvTa.lt in s0-e of the nort import-i.nt potato-
Eroeowin g sections of the Unitec' States. It is not serious, ho-'ever,
outside of the Mi.cdle Western States, icco.-Ar.i, Ohio, Illinois, Indiana,
and .ichizin, an.i workers in this rojiion '>.v- .stimat-rd that the losc to
the crop due to this trouble r-.ns from ]0 to ]8 per cent, or a .uner?.l
aver._te of 14 ;oer cc.-.t. The -:.vcrare an:-.ual ootato crop of these Stats
for the -cars 1926 to Y-'28 inclusive 9nou".tcd to about 80,000,000
bushels. This is onl.' 36 p r cent of the crop t'.-.t mizht have bce:-.
harvcstoed 7ore it not for this insect, a los- of 13,000,000 b',sh'els
valued -it over $11,000,000 at the rather lov: rc-ional prices.
Damage b- the nea aphid (Illinoi-i. nisi Kilt.) is cstim-'.tod, both
in the Middle Atli.ntic St-trs a-:.d i:i the :Tort>. Centr?.1 States, A. te
entomologists *and other vror.crs of thcse re-ions, at 15 per ccnt. Mr.
J. :3. Dudley, as a result o' si; --ears' invccti-.ztions in the cImnery-
pe. section of south-ern Wisconsin, L section cont..ini'n practic-illy
half of the pe-t c-.neries of .the Stite, estimn.t.-o- that during; this
period the averaz: .?-i"nal loss from dcn'edations of the pea ?p'.id"
amounted to 11.66 per cent.
Assumir.- that 15 per cent of djnia'-e occurs in the pea-ero'.ving
sections of Wisconcin, Illinois, -tnd Calii7or-ia, the $11,797,2'80 -:vorth
of peas raised for all ourposei in t'esc States in .923 wa.s onl-" 85
per cent of the crop that .vould have been possible "'.'ere it not for th-is
insect. In other E.ords, ther; w-.s loss of $2,082,000 worth of peas.
The pea aphid is also :n import.,:t factor in Nc7 Jerzcv, DelA.tare, .-.nd
-, .. ;i ue d -i-ruu-l loss izn
Maryli-a;d, but only sporadic.l". Alo'.vi '.itributed rul loss in
these St-tes of 5 per cc--.t -'e -'ould "_ave %- ,'iditio.-.nal $53,000. Some
losses probabl:- occur in the i:.iporta-.-t mYr':et areas of the South
Atlantic n-.ni Gulf St-.tes ':Id in the import.-t cnt i- St-.tes of
Minnesota., I'Michi-i, .Tc-,, Yor':, ?.nd Utah, I.-d there is some injur" to
clover and aiflf.lf.
MXIC.U: B3AO BT.TI= .
The M.7icinr. bc-n beetlc (Cil.:.n. co'rru'.ta Hu]s.) is still too
new a pest to mrr--e possible fair eftir:n-: of t'.. doaze t'.." it ill
in rll probabilit.y cax.be. ",. T. .Mo7ard .lccrt.injd that on t-he check
plUts at 3iinin.m, Ala., t'is. beetle rerovcd 48 per cert of the ,.r.
foliaro. He believes that fol-4,-o in.;-ur, of over 40 per cc:'t at or
before the ti-le of blo-sornir.n redkces the crop in direct -roporticon
to the aznorznt of dofoliLation, while o. h.o other hand. reec br-.ns
eb-aI withstand a 25 *per cent .'efoliation *'it-out sparenB rVd'rti'n in
;1leld. The 48 per ce-it dcfoli'ation f-i-1'e obtair.d y. 3ir-i:.". -i is
believed to be entirely too high for t-he entire beean--rowig area of the
United States. In the easterzi area -."ere this insect is gc':.-rally
established bears occupy apnro:ir?tel'- 70,000 acres. Of this acreage,
nearly 30,000 acres arc- devoted to dr.,- bean production and produce o-.-er
350,000 bushels of beans valued it about $1,500,000 (1-28-1"29 estimates).
LJBR A RY
wrATh PLANT BOARD
The rem .i-.dcr of the bea-n acreae produces approni-.Artev 50,000 tons
of snp beans valued at about $3,500,000, ,o total of $5,000,000 worth
of beans (1929-I029). T.e:-et:--four per cent of this would -jinount to
$1,200,000, _nd' this we rj!:ht consider as a very rou.,h estimate of the
d?.m-ie this i:..sect is cap'.ble of inflicting.
Spraying to control this pest costs about $6 per acre, and on
70,000 acres would cost $420,000.
STF.IPED CUCUM3ER BE3TI
The striped cucmuiber beetle (Diabrotica vittata Fab.) is one of the
most serious pests of practically all of the cucurbitaceous plants. The
Zrc'"ers in the melon and cucumber producing ections of the country
estimate the daj.T-e by this pest at approximately 9 per cent. This insect
is not 3. pest in the i!aportnnt melon- rowvin- sections of California,
although the related spE.cies, Diabrotica trivitt2ata Mann., is of economic
irnporta.:-ce in that region. The value of cucurbits, cxcl,-sive of
ca:taloupa, amounts to $22,000,000. Nine per cent danize would gi-.e a
monetary locs of about $2,000,000.
I.PORT- C-A3BAG- W0Pv.
The imported cabb:'je worm (Pieris r-.pae L. ) and a few associ-Ited
lepidopterous larvae. vcr:'- mat-rially affect the cabbhc and cauliflower
cro',s of this country. These insects, according to Huc'ctt on Long
Island, reduce the cabbae.e crop about 3 per cent and reduce the value
of the crop harvested ap1:'o
estimate this d a-.ae at %pyro;ii.ately 18 per cent. Following Huckett,
the 3 per cent shrinkrgge of the crop of 1,027,000 tons of cabbage (1928-
1929 avergTe) amounts to about 3,200 tons; at $22 per ton this is
$700,000 and of the crop that was acti.1ll1, harvested there is a reduction
in value of 10 per cent or a loss o? over $2,000,000, r. total loss of
nearly $3,000,000 occ.-isio:.e by this insect and its associates, the
cabb%:ec lopper (Auto)r.:'-. brassicae Riley) and southern cabba.9e worm
(Pieris Drotodice B. & L.).
The danaze by insects affccti:-.. forest trees a.d their oroJ27.'s
may be divided for our purpose into four cateQories: First, b',r-," '-etles
in the Wect; second, the spruce budrorm in th:c northeast; thir ,'. r
defoliators thro-:.rL,-out the country; and, fourth, tho.L iLsc3 ; C'-2
Q32,Ze forcs p'o..crts after thc: leave the woods.
One of the nost serious forest-insect posts of the West Coast and
Rocky,- I.ou:it.nn re-ion is Dendroctonus brevicomis Lee., in its attacks on
the westeix -ellow pines. The Forest Service estin.tes that there are
76, 000,000,0(0 board feet of this ti.nber now standin:, in Oregon. Work
carried on by the Bureau of Zntomology for th-.e past ten years indicates
t'-.at in certain territory there is arn .vve-c- an-u cn] ideletiorn in timber
of 1.3 per cent. This, howvcer, is a se-'rel.;' i-ctC't district. In
areas w"-crc the infestation :-s noro of n.-n c-'dcic c...:-acter t.zc average
annual loss is about 0.724 ncr cent nf t]hc st...d, an.d it is eztir.-tcd
that 0.75 per cent i,: a fair fir-re of th- a:-.,u-.l los- o-;cvr the entire
yellov pine area of Or.:7on. Th-.t means 570, C000,000 bo-.rd feet which
at a value of $4 per thousand mjounts ;o $2,)280, 000 pcD r an:-ur.. In the
Modoc National Forest and surrounding private tir.berl.nrd surveys carried
orn by the Bureau of Tf-tomolo,;. for t6.c nocriod 1921-1927 s'-.o-'ed lozsces as
high as 3 per cent doiring the season of 1927 vit. an nver .e for the
period of 1.3 per cent, and on certain limited acr-ecs losses h?.ve ran
as hi;h as 50 pur cent of the stand or as hith as 14 oper cent in a single
In the Kaibab rational Forest the Black Hills beetle (>'ndroctornus
ponderosa.e Hoj-.) between ]20 a-nd ]25 depetroycr. apnro:-im1-.ttly
15 per cent of the timber or 150,000,000 boa-d feet p?r -enr. This is
unavailable tir.-ber at present but it .-'.s 2 hi"h future potenti-il value.
Considering all of the westernn pin:s, s-racc, Dou.--las fir, and
similar troes, drnmage by bar'h_ beetlic, (Dentroctcnus zipp.) >2.s ranked
from 5, 000, 000,00 to 6,000,000, C00 board feet ncr an:U-.Ln, valued at
from $15, 000C, 000 to $,18, 000, C000.
The spruce bud-.::orm (iarnoloc--a fuj-fera.a Clen. ) in the northwestern
pulp-rood sections, ebr.bacing. WTine ard eastern Canad'a, during. a lO-C:ear ,-
period endin; in 1C20 destroyed 25 vcars' sup-ply of pIpl.'ood (lTtional
Progroran for Forest Roservatiorns, by the American Tr&e .tssoci-.tion, 1926).
Pulpwvood is roughly valued ?.t ''10 per cord, and 250,000, 000 cords -"ere
destro;.,eO during th--e 10 -ears of this oa'.tbre.-, 9n .nn-.-ual loss of $250,000,
000. Vie:ed from -.notheir point, a cord o.' wood rou-'hl' produces a ton
of paper and this paper is valued at from .i .50 to $70 per ton or a yearly
loss to the paper industry, of at least '1 .00, 000, 000. A loss that is
rather difficult to r.easure but h.ich *7ill run i.ito vcrr vast fi-ures is
that occasioned by the necessity of shifting: the vilp-'ood operations in
this country from the northeastern section to 1-he South and Test. The
pulprrood industry, is heavily capi-talized -i:..d the- cA'-rc of location is a
very costly one. The last tu'i'-orr' epidemic preceding: the one recorded in
this paper occurred about 35 "-carz before it, so in order to .Tet a
fairer distribution of th.e loss '"L spre_,1. the dLrA e over the period of
outbreaks. If a loss of this magnitude occurs in 10 .-ars out of 35, it
will averae- $71, .-.-00,000 p.r annum on the ra"- product.
In a recent puolic-tion of the Forest Service (Statist.c-al
Bulletin N'o. 21) ver7, careful estimates by the Bureau of 3ntonole.":y on
the d.mna-e done b-- insects to the several t1rp.- of forest r:ruct.s, as
ti:s, polus, coopraee, etc., range from 0.5 urocr cent tv 5 per cent, and
in the a.cr~rete losses of this type aov..unt to $4C,900,CO00,.
As other d.efoliators cause danax.e estimated at -.bout '5, 00, 000o a
year, this nakes a ..zrnd total for insects attach:irn forests and forest
products of `138,300,000.
SprXTce budvo- i .................... $ 71,400,000
Insects attachin-1 forest
products. .. .................... 46,900,000
Baork beetles .................. ... 15,000,000
Other defoliators................. 5,000,000
,138, .300, 000
Then there are the ter-mites (R-eticulitsarrmes *pp.) lich on the
6,000,000 far-.s in the United States arc -lw.aos -tt work. These insects,
however, are ir.ch more troublesome in the '.-T.rmer parts of the cou-ntry,
so we :have divided the country into a southern region and a northern
region alon.e a line from NTew Jersey to ITebraska%. In the southern part
of this territory farm building's are valued at $2,900,000,000. It is
estimated th1t the termites in this territor- depreciate farm buildings
approximately 1 per cent per year; this reans th.t there is an annual
loss of 629,000,000. But the rer-in'-or of the country is not ir.iiune from
teimito attack. Illinois, Indiana, Ylew York, and the other States all
report da.-:.-e bv these insects. Allowi.:-- a depreciation of 0,01 per cent
of the total farm builin-s in this reion, .7e have an'additional '290,000,
or"a total of '29,290,000.
Da?.a.;-e by tarr2ites is not confined to thc rural districts, but
probabl- a lo'..r percentage of dc:a-.e of the total building valuation
prevails in cities and towns because r'a.-iy of the buildin'l-s are constructed
of stone, brick, or concrcte. It has brcn found ,ro-'it.ble to protect
wooden buildings from ter-:.ites b,- an ndditi-r- al investment of from 2 to
10 per cent; This neans, over 50 zears of deorecittion, from 0.4 per
cent to 0.2 per cent per ,nu.-
ST 0.-.7?_IJT' I.S"CTS
It is rather'difficult to separ:.tc th,: da-r.ae occasioncd by the
several insects that attack? stored r-r:A.inr. Goc. A. Stuart (Gen. Bul.
393, Pa. Dept. of A-r.) estimatcd that the b .:rc by -the .rounois
grain rioth (Sitotr: a cerealella Oliv.) in Pcnns4lva.nia -.lone ran from
$1,000,000 to .?3,000,000 O n:ua].'. Pcrez S3irm:--s found in Maryland in
124., front field c 7;.i:. -..tionls of stan.in- grain ripe enough for harvest-
in-, th'at 0.26 to 2.06 per cent of the --h.et v.-as infcst-d by this insect.
In 1922 r. A. Back a::d F. T. Cotton foun. t:at ir.festat' ns at harvest
time a-ounted to 2 per cent, and late thresh:ing ;avo t'.hese an
opportu.:ity on :.iany far-.:s to Cecvelop to infe!t.ations involving from
60 to 90 per cent of the crop.
T'c- rice weevil (Caler.ra or.yzac L.) in 1919, in connection iith
the An:oiumiis :-rain r.oth (Sitotro.a cerealella Oliv.), was found in
70 per cent of the -Leat shipments orilinating in OkaLo.oma, and in Texas
P8..7 p-r cent of the shin-ie-ts ver,. ifest-d. Tir nz the ".-eriod 1917-
1921, 5 per cent of all of the rvh.at in interit-.to cor-'erce ""- .-raded
down ori account of insect injur:.. The entj-..1ol,:-ists of the "'-`.cat bolt
estin.ate that 7 per cert of the wheat is da'ai:,-d by th.e 1.-oi.rois :rain
rioth alono. Back '.: J Cotton (Fairmcr'z B7.3. 14C5) re-,.rt that in 1?22-
1923, 13 cper cent of 7,802 crar lods cf :h,^-.t uLrrivi; in Balti.ore
'raeed "s-'.ple" an, in 1C23-].9'4. c0 ;jcr cent of 2,860 cs.r-loads 7r--ied
"s-ir.le" on account of the presence of weevils. This v.'hcat *.7.s mostly
fro:.i tVie Middle Atlntic States. Thse two sea.son.s, ho'..-ev'.r, vnere
outbreak years, and in 1924-1925 the rpercent -e of car-loads ni-'i.ei
graded ":TeevilJ." (tl.2 old irade "s-npio" lavinl; been abandonc. for
weevil injury alone and v.'heat iinnly pl-1cod in its srade .i.d the rord
"wveevilTI" added) was 4 per cen:t, which h la?.cod it subject to a discount
or c:xcnsc of cynditi.nni:- of at Ieat 3 cents per busiel. Allorin-r 4
per cen-t of tl.h0 hcat of the U-it,;r Statcs (or son.e-.hat over 56, 000, COO3
bush-els) to be -;:ra'd co.n on -cco-nt of rr..; pets, we w'uld -.ve a
ronet-ir- loss of -bo-it l,000,00 CO. T-.is does not take into accountt the
actual p..ain lost. :.'oreover, .t only consideers t,.-.t -rain t`' t is
actually inspected in corm-nerce, .?rd.;;Q the total production, a consider-
able qua-:tit:- of 'Y_-_ich in, hcld on the fcarnr for feedir:, scd, or for
future s-les. Probably :.e".-er loss is occasioned in kOCT'in- the grin
in condition after it reac'`ed the elevat..rs or mills t:-i-.n at the tine of
MWhen infest-.tiors are at all severe it is often necessary to
screen and blow the -r.i. These sc'oeiiiA s are of very sli.-t 'value
wh.en compared to the bhole beri'y -vh,..-at. There is also a secr.dary
effect of infestation of rai: due to hLatin:.
In Floriidp. weevil e--.v.c to corn ,as esti:natel at 10 p'r cent
in 1?16 -tni in South Carclina in 1911 at 13.8 -.cr cont. The ento-
rnolo-izts of the Corn Belt :-have estiiatc.d the da-:.-e due to t.'ro species
of Calen.-ra at 18 pr.: ce-t.
In Goor-a. in 1923 S. E. H.cCle-.don found th't 42.9 per cent of
the ears of corn were infested b: tihe rice weevil before harvcstinz.
Shiplments of corn inspected at rcmnan, 'Te::., were fou:-.d to be infested
to the extent of 7.75 per cc-t.
Asmran-ug the ur.ch more c-nservative of thse figures, 10 per cent,
as beinr. the dar-n,-e actu.1:'- done to corn by -'r:-' -sts, the 486,000,
O00-bushel crop of corn ;ro'n in the southern part of the country where
these insects are imnpcrt-nt is but 90 per cent of the crop th`at mirht
have bee'. consiir.;e, as food and. fet- ':ere it not for thise insects. TLat
is a loss of 54,000,000 bushels; or, a.t t.e 1927-1929 price of about 75
cents per bushel, $40,500,000 for the South alone. The rect cf the
country is by no .--eans free. It rust b- borne in ii.d, h.-vcr, thA
this is not one insect, but the aj-re ate of several the w7or' c of which
can not be easily separated.
Ta2-_iin corn, wheat, and other -rains to-:ether the da'i,-o4e by stored-
product pests rust a.-oui.t to at least '5C,000,000.
Clothes moths (Tineola b'selliella Ban. et l.) are usuall-
considered as et-'re' ely triflii_ insects but few havr considered the
ag-regate losCes occasioned by thcr.. "
To "de coi:serv-tive, we will consider t.e city a:.d town houses with
their cedar-lined closets and houseo:eeping Tfacilities as imw.une from
these pests. Thecy are not, ho.wever.
On the farms of the country there is a popul-otion over 10 -ears
old of 21,500,000 people. Of this 21,500,000 there is probably iot a
soul who Las not lost '" an average 50 cents worth of apparel by these
pests every- y.c.r o'f his or her' lifeti:'e. T'is would mountt to $10,800,
000. Certninlyr the averse loss is f.r above this figure.
DISMSE-CARRYIiTG I TS'CTS
Another phase of insect d,-. 5.a-e is the loss occasioned to people of
the United States th'_ro-ih insects that carry diseases. A few of the most
strikin- diseases of this type are malaria, yellow` fever, ship fever,
Asip.tic cholera, dysentery, Rocl.;i Mountain spotted fe ver, and pink eye,
in this country.
The ravr-ies of i-ialairia transmitted -p '-,pp. a,2?.ve been estimated
as producin; directly and indirectly half of the entire mortality of the
hum-nan race (Creighton, 21c3yclo- oi". Brittanica). Sir Patrick Manson,
workin.- in tropical countries, 'is tWat z alaria causes more deaths and
predisposition to deaths th-in all other diseases that attach mankind
For the period 1900-1907, Dr. Howard pabllshe1 d fi.,ures (Bur. :-it.
Bul. 'To. 78, 1909) on sixteen northern States !Ihere the deaths a. mounted
to 4.9 per 100,000 population ?nd actual deaths for these States to
1,583 pcr-s s per -ear. Those are all northern States, and it is recoG-
nized that .nalari-i is r.uMch less prevalent in the Iyorth than in the gouth.
Dr. Howard eotiiate-I. that for the whole Unite'a States. 15 persons per
100, 000 is a very fair fi;-:ire.
Buit the losses by :e-.th are orly a snall rprt of the loss occasioned
by this disease, as usually it is not of a fat.l nr.ture. Studies m.Ade at
the hospitals of Rome .-ow that the ..-.ortlity hospitalized malarial
patients .-o^rterd to only 7.75 rer tho`.us--ind. In all pr'rolubility, the
number of c'3 ths,' considering all the cases of malaria, would be less
than 5 per tijs.. "Lhe great lo:.0 is in t'e tiLe lost by the indi-
vidial whilo sick, in the re.ucod vitality and resistance of the indi-
vidual occaslor.o:.d by the disease, and in t'at factor upon which no value
can be set, the'confort rnd -.ipplness of the indiviLdil Limnself.
ferric2 Las estin-ted (p-hrl'r Scie.:.co '::thl,, A1ril, 1,03)
that in 'the 5 .BSttes, LoAisinna ,l.b-, MiszEiir i, Qunr.i., a.>.
South Carolina alone, 2, 000, ,0c to b, Q.O,,C" v-;', of vicn'-.esr ire
traceablo to this o:ne ise.aso, tnd .s .i A4rect rcsilt jf t.he
)prevalence of this .-ise?.s- r.n'c.C of the richet an,. in A'-erica, an'd
probably the second rich-est ai'e' in the vorl'., the .ic"sipi.)i Delta,
is only valued at fro:-.! 10 to 0 -cr "cru. This l .-nd car. ar.d oos
produce, when cultivatc&, fro;.. 1 to 2 bal^s of cotton ;,-cr :crc and
should be worth from !.200 to 30. The lilitin..- factor is :-laLria.
The v:hite !.:an c-.. not coirfortabl:' live1 there.
Sir Ronal. Rosc ::.s attribuitec t'-e h.-"sic. p .e (e-:..ncrltio. of one
of the stron.;est races on earth, the Greel:, to thec introduction .of
malaria into the3.r country.
As I have sai'. before, the d6ept:i r.ate fils to cve7t indicate the
economic loss occasion-d by this inr.oct. A sna)l itei; of the cost,
narnely; screens, ".io.ounts to rroun'. $10,000,000 c n-r an--..
If -.e have .?. r-ortalit.- of 15 pqGon- per 100,000 an? if the ratio
of mnortality to tot5l cases Tn-'.nr r.ieAcal care is siuilir to that in
Rome, ie should have in this countj.-y 1,530, 000 persons annually sick
with m-ialaria and. uwider .n-ed-ica.l care, anl the total number having the
disease would prob-%l"- be twice that figure.
Dr. G. 0. S.itX,of the Unite? States Geolozical Survey,, in recor7.s
na-le of the topographic fiel-'. workers of the Survey ascortainc?. that one-
fourth of the active capacity:- of the '.ise.5."e1 indivi.ual vu.s lost.
Mr. D. L. Va': Dine (A-ier. Jr. Pub. Health, Vol. 10, ITo. 2, r'. 116-
119, Feb. 1920) carric, or a very intensive st :ily on the losses t) rural
industries throu-h nosnuitoes in a conp.ar'.tivc!-y or.all coi-.-:.-.nity in
Louisiana, where the ccn'itions on 74 far-s su:r'-portin.: 295 iniiv'.a-,?ls
were analyzed. These ztuC'.ies '.ore na'.e in 1913, at .'::ich tin.- the
population in this cor.riunity -.Ls cla.s7ifica. :Dn an ?.a.e b',-is as follows:
Nunmj.br r- -'be.: I'U r.i"er I -11) E r
Ur-ler 8 yrs. S-12 :'rs, 12-13 -yrs. over 13 yrs.
Male..........9 14 2? 82
Fen.le ...... 24 13 26 87
A careful study, of the hospitalize; cases sh':e-od- t-hat .'irinc this tire
there were 970 cases of r.malaria. In this stud.- an effort wIas na'ce to
ascertain the actual irc'istrial loQs, occasi .ne. by this .isease. Of
course, sick children under 3 years "-ere rot a c'irect i'.rustrial los1 ,
a ohild. from 8 to .12 "ears of ace 7-_s con.sit.cred as one-fourth of an
* adult, and all over 18 years old as a.ults. The comNutatio:x vas trade
on the basis of P.dult, rale work 6..ys, an.-. in the conputtiton, fe-rale
tine was considered onc-ba.lf that of .-.%Ilc timec. The tl.:it lo0t rss 625.5
days of adult tine b-y hospitalization or under care of a doctor.
Further studies of time lost b-y cases not reported to doctors, and
the time lost br those attendin- the sick, ,i've a total of 1,056 days,
reduced to adult time. In a cor.r.unit.y of 299 persons this averagess
3.56 days per pcrEo-n. The actual time lost by each case of r.al.ria
was 6.42 days per year.(adult tire).. Basin; our figures on the esti:. ate
of 3,000,000 c?.ses of ra.laria occurring a'" nun.lly in the 'United States,
we have a time lozc of 19,260,000 adult dr,ys, which, valued at .2 per
day, -'.ounts to o38,520,000 loss to industry.
Fe.-! entomolo-gists have considolro"'.;the insects affecting domestic
animals as ainon- their import--it pests.
The screw vor:: (Coc.lionvi c ::' cellaria Fab.) h.-as been very carefully
investigated by the Bureau of Bntomology and. the ".Pj'.a-c is knovwn to be over
,4,000,000 per :'Co!r. This insect has rendered. nc lon-er available for this
industry lar.-e areas which were formerly productive da.lf-raising sections.
.Then we consider that rn.-e country is not a-aptable for ir.ied.iate transfer
to far.,nir activities, the depreciation of real. estate values in these
areas is a trcr.e-bous feature in itself.,
The cattle grubs(Tyoderma spoe.) are also serious live stock pests.
Nineteen per cer-t of all hides, cor.nercially rriraed.o, are classed as ;rubby,
(Dept. Bul. NSo. 1369,' F. C. Bishopp, et al.). Discount for Trubby hides
is 1 ie-.it per pound, hide weight. Apyroxinately 16, 0,0,000 hides, not
counting calf :nhins, are produced anr--all,.r of which h 3,340,000 are classed
as r-abby.. Cow, steer, and kip hides average rou.:hly 45 pounds per hide,
giving a net loss of $1,500, 300 due to hide da.-.-;e alone. To this Y.ust
be added the -'e in storv-e indirectly due to ,'--Mbs, called salt stain,
the da-v..'.e to calf skins and that which occurs in hides e.rl.r and late in
the season which are not included' in these ficlures. Bishopp (loc. cit.)
figures t--is total loss to hide 3 at' bt-oer 5,00,00 a 0,00,000
Thiis tes no account of annoyance to stock .-hiring oviposition
of the flies and irritation to the host by th.e larvae both of which are
reflected in reduced milk flow and failure to pat on flesh. Death loss
which results occasionally front cattle -rab attacks alsco is not included.
About 70 per cent of the beef -..r&.uced in the United States comes
ori-inallyr from the Southern and Weot._n States, judging front the numbers
of cattle other than nil.t co-is on farms. Th-nt mcens approximately 70
prr cent of nearly 5,000,000,000 pnun.-ls or about 3,53), 030,000 pounds,
co.siderinc only federally inspected beef, -'_-.ich is the .-reater part of
the beef supply, At an aver-.ve price of 16 cents per pound, this southern
and western mc,?t was valued at 560,000,000. Germnan o:.:p)eri.ients showed an
increase in :.-eat production of 5 per cent in cattle from which =ribs had
been remove_ over those which were allowedC. to rcnain infested. This is to
say, the production of southern and western beef is about 95 per cent of
what might have been produced hlad it not been for these insects alone, or
a loss of nearly $33,000,000.
D-.irYT:e:.n estimate loss of :i-A!:- at front 10 to 25 per cu:.-'t '.rin-
the period. of fi:- activit". (1 to 4 i-L.onths), 10 T).-r ce.-.t loss in 2 2-.ont-.s'
milk ar.,ounts to 250, 02, OX ;?.llo-s :crth:i at bul: farm price -XI, 0'.., QDC.
Collectin-; all the losses cccrsior.e- 'b cattle nrubs .. other flies
Los: to da-ir:- ,rro-..icts....... $.5 ,,C'r O., :
Los3 i.2 ef. ................ 30,07., DOG
Da.. ,-eC t hi s. .. .......... 5, C, CC
A "-. ,CX ,0,#
Summary of Annual Losses Occasioned by 34 of the More Important
Insect Pests of the United States
Antnonomus zrandi s
K:.liothi s obsoleta
Ac r idi ie
Calendra oryzac ot al.
Lyctu': spp. ot al.
Lopt i no tar s.a dec cmli-aeata
Haamatobia irrita-'ns et a].
Conotrac h-elun :-icnuphar
Aphis pomi -]t al.
Tir-neola Dielliello ct ji.
Diabrotic i vi tata
Picri7, r.:-te et 2)..
tomato, and tobacco
da.i ry products
applt2, pear, p'ach
ar K'1 e
clothinr7 ct al.
c ?2r-it :tto'~pc)
c a.b j *.--r
$924, 440, 000
Boll Weevil D.'---v:e to Cotton ns .sb'V.:ted by the
U. S. B-:ircmu OTf Crc Est-intes.
::11-1.-1 loss o2.' cot tor e.-pr-sscd :
::in tei-ms of "'ei-:-tec: .vcr -.;e rTcr-: Ot"-er
::ce.:t,?.;s of t:i.c stir.atc.!. crop in: Insects
:: t.e abso- ce of in-ects :
:Pcr cent :Per cent
UNIVERSITY OF FLORIDA
HIl~lllll3 1 2621111 09226 93891III llll 11111 BtII
3 1262 09226 9389