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Scale insects and whitefly control by natural means.

UFLAC





SCALE ITSEOTS AID I ViITEFLY CONTROL BY 1TATURAL IhEAIS


Introduction.


"Small fleas have lesser fleas upon their

backs to bite them. These lesser fleas have still

Smaller ones and thus ad finituma."

S Under natural conditions, no one species

of insect post is likely to become exceptionally

abundant. OItbieaks do occur from time to time ap-

parently without reason or cause. Still when the

relationship of cause and effect is studied' carefully,

one finds that for soeic reason unnatural conditions

prevail in the irmmediate neighborhood, An illus-

tration of this kind may be cited in the Colorado

potato beetle, which in its native haunts is, com-

paratively speaking, a rather rare specimen. Under

unnatural conditions, however, such as the general

introduction of the potato plant into large regions,

as occurred in the West during the seventies of the

S last century, this potato beetle increased enormously

in numbers. This brought the potato beetle into

a new region and a region free from the natural

controlling ele.oents of the potato beetle During

the early years it became a pest of very serious











importance to the agricultural people from t'-


"Pocky mountains east;wards. Especially serious was


this pest in the r.iscisaippi Valley, After combatting


it for a time by artificial means, especially by


the means of Paris Greon and .i~ondon Purple, the pota-


to beetle has largely disappeared in the potato


fields, cand since potato growing has become almost


universal in'that section of the country the enemies


of the potato beetle have become almost as thoroughly


established as the beetle itself.


Another illustration, rhich may be taken


from our immediate section, is .itht of the San Jose


scale. It is only a little over two decades since


this pest was introduced into the orchards of the


United States. At first its devastation were almost


complete, later people beg-an to doubt the seriousness


of th6 outbreak and still more recently, the.San-Jose








scale has not been considered a serious cnemy in the


humid portion of the southern states, especially in


the gxulf region. 'Where peach trees are planted in


extensive orchards, it becomes a pect that has to


be reckoned with. Still it is not considered an unsur-


mountable difficulty, even if the- San Jose scale


does a near. During the early years of citrus cul-


ture in Florida, the mo"t curious of the orchard posts


known wvcr the variou- cpocies of soale insects.


At the present tine, no citrus grower consider it


at all alarming to find prcsont in their gro.os a few


trees infosteaI with scale insects. As a matter of


fact, one of the most oe xport, if not the most xpoert


citrus grower in Florida, has told us candidly on the


floor at a mooting of the Iorticultural Society, that


he really welcomes the presence of one or two scaly


trees in his grove, since if he has one or two scaly


trees present, lie always l-nows where to find the agency y









which will koee the scale insects in check in the


most economical manner.


Profess or Quaintance lists over sixty


species of whitefly -O .in. .. Florida. Only


three or four of these spooiec rc likely to over come


to the notice of the average horticulturist. All others


are practically ua=nown oxcepting to the systematic


entomologist. Those species of whitefly that ate con-


siderod endemic by the systematic entoeologist rarely


or never become troublosonme to the h'o-ticulturict, not


because ond mic plants are Cnaff'ootod- by thom but because


the balance which nature has struck betvwe n various


individual species in her catalogue is such as to keep


those whiteflies perfectly under control.


By running through the list of serious insect


pests to cultivated crops, es ocially of the fruit


trees, Ywe are at once struck by the large number of


species that are not native to the particular region in





-5-


which they do their mnarimum damage. As a rule the


species of insect posts, when first introduced into a


region, increaco prodicLously in number, becoming so


abundant that they are apar-ently going to devastate the


entire industry. Artificial means of repression are


generally adopted with v..rying rOsults in officioncy


and profit. Later those insect -ests may become almost


omnipresent in the region. Later they decline in abun-


dance and finally ta o their place among posts which


damage the crops only occasionally.


This condition of cquesences on the part of


insect pests is not an adaptation of the crop to protect


themselves against the particular insect posts, but


rather a striking of the balance by nature to keep those


overwhelming numbers in check,





-6-

San Jose Scale.



Tho study of the laws of int;e-relation


between the abundance of species and the natural sur-


roundingCL is a very complicated problem. So many


factors come in to vary the rocs.lt that inI uch time


must be consumed by the scientist in getting the


correct appreciation of the conditions. I'y meaning


in this matter will be made mcre clear by itAling a


specific exo:aLrp. By reverting to the outbreak of the


San Jose scale vhich occurred about twenty years


ago, vwe will have a good illustration. The presence of


this scale was found at about the same time to occur


in the peach orchards of Virginia.. The earliest re-


ports that we have of the San Jose scale occurring in


Florida, came from the westen most portions of the


State. Peach growing had lboen conducted in there for


a number of years. ITursery stock was secured from


everywhere that it could be purchased. The trees





-7-


sooned to thrive for a number of years. As a matter


of fact, the region wass her.ldod as being particularly


adapted to the growing of this crop. It was thought


that the climate was so mild and favorable to the


peach tree that it would be impossible for any onemy


to affect it. After a very few years of unprecedented
I .
dovelopmont .in the peach growing area, the trees began


to nystcriously blight and die. Investigations showed


at once that the trouble was duo entirely to the pre-


sence of the San Jose scale. The early peach growers


had succeeded in producing a number of orchards


entirely free from these pelts. Later more aggressive


orchardists gathered their nursery stock from all


quarters of the United States to plant in this section,


Unfortunately some of this stock came from sections


infested with the San Jose scale. This introduced


into the region a :lot of insects. These in turn flour-


ished in a 'way that was quite unprecedented in other




-8-


-prts of the United States, due to the fact l-rgely


that there v1as practically only one month of the entire


year during- which their rapid growth ceaccd, thus ac ini r


very materially to the annual .rate of increase. Aftor


the San Jose scale flu rischod in that region for a


numbere: of years, anda after it had illod off a con-


siLerable -roportion of the peach trees set out, it


wa: noticed that there was a distinct diminution in


the number of scales present. Investigations showed


that pJaoh orchards, pear orchards. and plum orchards,


that had boon thichly infested and even encrusted


with San Jose scale the year before oere found in 1895


.completely free from the pest.



Discovory.of San Joso Scalc Fungus.


This very significant fact remained unnoticed


ountirely by the average orchardist. It was ascribed to


luck, cold winter, mild winter, or any other condition


that might happen to exist... To the scientists, however,









the phenomena was of greatest importance. It required


however fully a year of diligent and painstaking


study before the real cause for the mortality among


the scale pests could be definitely determined. The


steps for proving that a certain agent was the abusee for


the mortality had to be taken with the great care. And


even after the matter had booeen proven most conclusively


from the scientific standpoint, it had.to be demonstrated

over again to be certain that no error had crept into the


work at any point. A second year.elapsed, therefore,


before definite public announcement could be made.

Life History Study.


After the fungus enemy of the San Jose Scale

had been definitely discovered and unquestionably iden-


tified, considerable time was required to work out its


life history, The work along this line at that time


was seriously handicapped by the lack of information in





-10-


regard to methods of proceeding for the determination


of the life history of this kind of fungi. Practically


all the steps passed over new ground and had to be


worked out upon new media and by new processes. Fortu-


nately the work was done so thoroughly that after a


lapse of over fifteen years no essential detail has had.


to be corrected.


Necessity for Teaching.


The first thought that comes to one, is that afteY


a discovery of this kind had been made, that all that


would be necessary would be to make the bare announce-


ment of the fact, and then everyone would hail with de-


light the new information. Fortunately or unfortunately,


however, the facts of the case are that fruit growers as


well as other agriculturists are likely to accept-new


ideas with a great deal of incredulity. It therefore


happened that it required years of teaching of the





-11-


facts and a continual repitition of the story to induce


even a samll proportion of the population interested to


accept the evidence as fact. As much as ten years later,


we find one of the most aggressive peach growers in the


State, saying that it required a great deal of courage on


his part to try the experiment of using the fungus enemy


of this San Jose scale for treating the pests. This too,


in spite of the fact that he had been, or should have


been perfectly familiar with all that had been written


on the subject. Even to the present day, we find scores


of peach growers who still consider this method of treat-


ing the San Jose scale as an experiment, in spite of


the fact, that one nan alone in Florida has supplied this


friendly fungus and treated ten thousand acres for San Jose


scale within the last three or four years. In addition


to supplying the fungus, this person has guaranteed


that the fungus will destroy the San Jose scale in the

orchard in which it is applied, and so far has not been









Called upon to make good his guarantee, Fungus material


has been supplied by this one man alone to Georgia,


Alabama, Mississippi, Louisiana and Texas for the treat-.


ment of San Jose scale in orchards. In all of these


states, this one remedy works decidedly well, In Georgia


alone as many as sixty thousand trees have been treated


in this way.


Treatment of Whitefly with 1ngus.


I now come to a more recent discovery and one

that has been given less general attention probably than


the use of fungi for the treatment of scale insects. The


treatment of scale insects has been so generally adopted


in the citrus groves of Florida that scores of spraying

machines are now idle and rusting where formerly they


were polished by use. The use of the fungi for the control


.f .the1-whitefly as not been given the thorough study


that it deserves until within the last four or five years.










So little attention had been paid to this matter that


the spore form of one of the most. effective fungi was actual


ly unknown until about a year ago. I merely mention this


to show how hastily and unsystematicly the work has been


carried on. In spite.of all this, we still have secured


a very large fund of valuable information by the way of


observations. During the last two years, one man alone,


who has made it his business to apply these fungi in a


commercial way has sprayed 750,000 to 800,000 trees for


other people. This is the correct way in which the work


should be taken up putting the work in the hands of an


experienced man. The work will then be done much more


efficiently and thoroughly than where every citrus grower


attempted to work for himself. Mr. Sterling of Deland


who has undertaken this work on a commercial basis charges


two cents per troe for the introduction of the spores by


the spraying method. "this is comparatively cheap as against





-14-


insecticides which cost approximately twenty-five cents

per tree to spray.

The Natural Methods.


I now come to the most important part of my


talk this afternoon, the part to which all that I have


said before is an introduction. After studying the


question rather carefully, we nay state that the reason for


the tardiness in adopting the natural methods for the con-


trol of insect pests are largely due to artificial con-


ditions.


In the first place, the introduction of the


natural methods for the control of insect pests means


a very largo diminution in the number of spraying machines


that will be needed in the work, consequently every agent


of the spraying machine manufacturers must perforce ignore


the advantages and divert the attention from the use of


natural enemies toward artificial means. He must make it


a point to keep preeminently before the would-be spraying









machine purchaser the various difficulties and failures


that occur from the use of the natural enemies. ne ig-


nores these difficulties or assails them to the use of the


other fellows machine When applied to insecticides.


In the second place, the use of the natural


methods would in a large measure reduce the insecticide


business. Consequently every manufacturer of insecti-


cides and his agents must hunt up the apparent failures


and disadvantages that occur from the natural methods.


These they must emphasize pretty strongly to men who are


expecting to use the natural methods for the control of


insects.


Lastly and by no means least, is the natural


apathy with which we' are affected. The horticulturist


naturally puts off treating his trees either for insects

8g fungus diseases until it becomes imperative. He then


has to use the means at hand, and such means as give


results quickly. irrquently he has delayed so long









that to make an application of the natural remedy would


mean a total loss of his crop for that year, Consequently


something must bc done immediately. Artificial means are


therefore the only methods to which he has recourse.


A-ain this whole line of work is a new and


unchartered one. It requires definite and very careful


attention to details, both from the investigator's stand-


point and also from the standpoint of the orchardist. The


natural lines must be studied and understood. When the


investigator has ascertained what the lines are, the


orchardist must familiarize himself with the conditions


necessary for success, all of which requires a consid-


erable amount of outlay in the way of brain work, a line


which all of us would like to avoid if possible.


The field is not an inviting one for the young


entomologist. He will not, get results quick and his


principal is likely to expect him to "make good soon".









He will find that it is easier to got a hundred'


dollars to spend in applying the "club" method than to get


ten dollars to apply the natural method. Then too the


scientists and their assistants have all been trained along


the insecticide route. The principal studies on the


natural control of these pests have been made as side issues.

(E.G. nebbers Studies; ravwcetts Studies, Rolfs Studies.)




o t-1 G al











Introduction. Small fleas have le, s 0r fleas u0on

an!c7 them.# Those lesser floa, have still smaller'
hrir "oais in

ones .-- te -- ... anEd wthus ad finittin. Unler natural

conditions, no oeie s ecios of" i" cct is ll to bec6l..
e:.coptionally abundant Duktbreakes to occur from i-e to te

apparently :v1ithou reaon or cause. St i l v hon the relationship

of cau:ioe and effect is studied o rofulll -one fids that for some
i

rea co1r unat L ra co di ions prevail in ti :'e imi re.iaete" noiihborl-ood.

An illustration of thisc ind ay be .:cit' the aolorada ora.

c tlo, which in native hannt. is C3.oIcavtiVely spoalint

rather rare spoecimen. Under urnatural conki ions, ho cver,

such as tIt production of the pSotato -lant into large regions,

as occurred in the 10st tring te sovent'ies cof -e last col:tl -, ,
increased
-"*








thiec potiatlo bntle enormously iO n numbr. o This brought the

1 tat. o beetle iontb Pa pn orei ands.L a region frhe from the

nat .ral controlling elements of the. -eotato beetle r l'Lo uin.

the car:ly y ars, it became a pest of very ser ious imnortanoe to

the agricultural pcorle from Ite roc'y mounntains east'y.ar.-s, -h.-c

ially .ev'rious was this oest in the ini isip i y alloy. T 5a

After cormbattin it For a timo by artificial means, escclal!.-.

;by the moe.ans of Paris .1-reen and I.ondon o urple, the po.ae beetle
and.
has largely diciappared in h el p ot to fields since potato Cr-i-o
increa d r +I

ing has beco meo almost univo rsal in, that C.Thic on of the coo.ntr;

thoe onomies of the p otato betle have baod almost as t-.'roughly

ectab lis hed a the bcctle itself.
; .
Afte cobatin^it fr atin "b artfical ean :.espcialy.




-2-


Another illustration, 01hich nay o taken **ror our

ijaCidiat'o section, is that of the San Jose scale. It is only 'c s

l. ec aides since .thls twas introdc i into the ochar ls of
theU TTnited Statecs. At fi';.t its devastatibns 'vas alr.most co :plete,

later people began to doubt the "riout~s: of the outbroel and

still more recently, the Sah Jose scllo 'ta.. not boon considered

a .seriou.I' neuy in the humid ari 1otortion Lf e southern statoo, oc-

pecially in the ulf region. !7hor peach trees are ~ in e:-

t enosive orchards, it beco:nos a nelat that' had's to.be reckonecd with.

Still it is not ooesiderei an unsurmouItable ldificulty, even

if the San Jose scale does .,rpear.

during the early years of citrus c-ulture in Florida,

the most serious of the orchard po.ts now"In were the various

species of scale insects. At the present time, no citrus

grower considers it 'a all alar-ing to Iind. resent in their .goves

a feu .trees scac.l insects, AS As.matter of fact, one

of tlhe 'tost expert, if not the rnos- ,oe c't citrus grower in

Florida, has told us candidly on the floor. at a meeting of the

*Ilorticultural Society, that .ho really weleonos the presencee of one

or 'two saly tres in his grove, since if. le has one or tv-o scali

trees present, he always, knows .;chore to findthe agency which vill

S .keepn the :scale insects in checkk in tlhe most eco'iOal aio

Professor Quaintance lists over si::ty species:

Sof :.1hitefly as .-;ro.:ing in Flo'rida." Only three or four of th- e-

species, aro lic'eiy .to ever come to the notice bf 'the average heoticul-

turist 3: a3-=@at. All otheo s are pra-cticac. ly, ni.. u n:. eeox.e-Tpting

to the systematic entomolo-:ist. Those secies of whitofly .tht c:re

considered ondomic i.e L by ,the ysto ati. entomolog0ist rarely:,






1 ii .
~- ."...



or never become troublesome to the Ihorticulturist, not because

endemlic plants are unaffected by then but because the balance which

nature has struck betvoeen various individual specios in Iher catalogue

is such as to keep 1-e acs w hitefl7- o e t perfectly under

control. "

3y running through the list of serious insect nests to

cultivated c-rop, ospccially of the fruit treec, we aro.at once

-strck by the large number of species that Ceo not native to the


particular region in v:hich they do 0.their Laxinum damage. As a r-ule

the socies of insect pests, 1v7ih nt uced into a region, increases


prodigrously in number, becoming sok5 -jal;t that they .re aTparnt

going to devastate the entire ind r. Artificial means of repression


are g-onorally adopted with vari-' reiIlts in efficiency and profit.

I'ater these insect .,e sts may become" al ost in, the

region. Later they 1 declinc.. in uila:dco l ,a.d. finally -0ct

among posts .ih d armare libhe ..crops L b ooT. Ooa i a na'll y..

T :his co ndituion O h. onte.prt o.f insect cEst-

is not. an aCdta` tionrof. the crop to i ooOt &theei elt es'aC inst0/a"E110

insect pests, but rather a btrihLinr of; toe balance by natu, to


Ioepn thocseo overwhelm ing numbers in, c c. *




i i ,'!
-4;--I


The study of tihe laws of into --ro action between the


abuCndance of species and the natural surroundings is a very cor-pli-


cated problem. So many factors come in to vary the results that


much time must boe cons t d. in getting' a correct a_-reciation of

the conditions. l.y meaning, in this m-atter will be maLde mo.r::ciloar


by taking a specific -exanpie. By reverting to the. outbreak of the

San Jose scale which occurred about -twnty year ago,- wo ill have


a good ill',1t--ation. The presence of this scale w.as' found at,


about the same time to occur in:the peabh.o tchards off Vir inia. Ihe

earliest reports that we have of the San-Jepo scale occurring in


Florida, came from thle western most porti-ons of the State,. Peach


growing had been conducted in there fori a. nnber of years. Hursery

Stoclk vwas from everyvihere that it could be i w. The trees


seemed to thrive for~ii umber of years.: Asa matter'of fact, the


region vwas',C heralded' as being particularly. dapdted to' the growing

of this crop. It was thought that the cli -t"e was so mild ahd


favorable to the peach tree .that. it woti'd: be imiosible for'any


e unemy to affect it. After a.-very fev; _ea,'r. of unprecede::tedc

development in the peach growing, toC t-ros .began to mysteriously


blight and die. Investigations showed co tht te trouble as









daue 'a -l-by to the presence of the San Jose scale.. The


'early peach growers had succeeded in producing a number of


orchards entirely free fro'n this poets. afterr more aggressive

orchar..dist.. gathered their nursery stock] from all quarters of the


United States to plant in this section. Unfortunately some of


this stock came from sections infested it-lthe San Jose scale.


This introduced into the region a lot of insects. These in

iC ", .. .


turn flourished in.. way that was quite Unprecedented in other


parts of the United States, due to the factrlargely that there was


practically only one month of the. c.tire, year during which their


rapid growth ceased, thus adding very.majerially to the ainual


tate of increase. After the San'Jose scale .flourished in that


region for a number of years,.and after i.t" ad killed off a


considerable proportion of the peach trees:set out, it was noticed


that there twas a distinct diminution in the numberr of'scales present.


Investigations showed that 1-eaelh orchards,! j~ar orchards and plum


orchards, that had been thickly infested and evcrifnsE encrted


with San Jose scale the year before vwerc found completely free from
VA I U f ':-o al,





-6-


the -est in ^ "." -- nt

Di covery I S I I 9"t


This very significant fact rtoaianed unnoticed entirely


by the aveor-ge orchardist. It vias ascribed.,merely to luck,

cold winter, nild winter,, or any other condition -that ni :ht happen

to,.: c:ist. To the scientists, however. the phenomena was of

greatest impo: eLtance. It required howevo;e fully a year of dili-


S gent 3and -ainstaking, study before the .real cause for the mor-


tality .amon~ the scale pests could b6 d.qinitely determined.


The steps for proving that a certain ag'nt was 'the cause for the

m ortality had. ,to be ta:en with the. greatest care.' And even


After 'the mat.ter had. bden proven mvost conc lsiely from. the

'cientific. standpoint, it had. to be. dcrohtrated over again to

be certain that no erro-r. had. crept it o thie work at any point,


, :A second year cla-:.eda, therefore, beooir. d-efinite public announce- .

ment could be *ace. j .


Life History Stud .i!' .

'A : ftorhle fune-u, enomy of the" San Jose scale' bad been .ef initeyi.
; t. ... : .




-7-


discovered and unquestionably identified, considerable time was


required to w-ork out -4tA life history, s-g4- a. The


work along this line at that 'timr a ty handicapped by


the lack of information in regard ti nothods of proceeding for


the determination of the life his ~ ory 1i~ i f p "1 rY of uingi,. Prac-


tically all the steps passed over had to be worked


out upon new media and oy nev process. Fortunately the vork


vas done :'o thoroughly that afotr &. lapse of over fifteen years


no essential detail has had to be corrected.


ITecessit ~l aching ttT


The first thought that comes to one, is that after a


discovery of this kind had been made, that all that wouldd be


necessary woIuld be to make the bare announcement of the fact,


and then everyone would hail with delight the now information.


Fortunately or unfortunately, however, the facts of the case are


that fruit growers as well as other agriculturists are likely to


accept new ideas with a great deal of incredulity. It therefore


happened that it required -years of- teaching of the facts and a


contiunua repitition of the story to induce even a small pro-









portion ,. ..;. a-
portion of the population interested t.d icpt the evidence as

f&ct. As much as ten years later, we iLnd-.on of the most


agll:resoive peach grove! er in the State, saying that it required


a great deal of courage on his part to try the experiment of


using the fungus enemy of this San Jose scale for treating the


pests. This too, in spite of th. fact: th he head been, or should

have been perfectly f.ilia-- With all that. had been written on the


subject. Even to-the present day, we find scores of peach


growers who still consider this *rthod of' treating the San Jose


scale as an experiment, in spite of the fact, -that one man alone in


Florida has supplied th fgs -oy and treated ten thousand.


acres for San Jose l:le w within the. last three or four years.

In addition to u pply the "fun,-is this person has guaranteed that the


fulngue will: destroy the San Jose'.scale in the orchard in which it is:'


pd'lied, and so 'far has not een "o make good' his guaran-


S,. .T .
teex 11iLO C'


. . I " "" -: '

',Fungus material has.b eeh suppli.ed- 'by this 'one man alone to Georgia,


Alabamia, MEiseississipp and.' Louisiana and Texas for the treatment:






O~a ~LL/Z-L-~6&6



.~~la w~~~b


/ /
^^ ^Zy ^^-^., ^rr^^J


<^<-


. IB










of Sal Joco scalo in orchards. In all of thcoe state, t- h one


remedy vw'orks decidedly well. In rGorgia- alone a 1..any as si:-ty


thou. and. trees have been treated in this Vay.



Treatment of Whie itefly with Fungue..



I no\7 coLme to a Licr recent discovery and one that has


boon given loe; gconoral attention probably than tha he use of fu-rni-


s n for the. traLtient of Icale inefotQ by 1e.e of p araYitic

fungi has talhon sA trong a d on h lori tr r

that ow find oreo and a iior da o h ;Ar: o oing s eth c'

in .prforen to ti noa o:; p
moans of praying o tions he .c of the fniS o th for the control

fil'lOZ~t il I L: 1! U 1O l ,o-
Tuhro iITofly not been given the thorough tnudy that it

decorve s. until ',i thin the last four or five yoarc. So little

attention -had been -paid to this -Iattrr that the spore .I of one

of the. most offootive fungi was actually unnrowvn until about a

year ago. I merely Ymention this to ov ho a ha and uncystom-

a ioC rth work has boen carried on. Tn spite of all this, e still

have ccnrol a vc-ry;, la-e fu,,n of valuable information the way

*of observations. During the last two -years, o'ne man alone, Vho

has nade it his businos to those ii in a corOra.

vay, has sprayed 1oe3 -tr t oes for qthoeri pole. This is

the correct way in which the .;ork should be ': taken up putting

the .:orh in the hands of an e:rperienced --.-'he work v.il then
Cf~~~~~~~ fl 1;OiiC ii ,....












be .done much more efficiently and thoroui;hly than o ev.cry....- it"Irs

gro:wer atteml.ptuc to .ori: for himself. '!hr. Sterling of DoLand viho has

unldertalren this ,/ork on a commorCcil >asis charges two cents per


troo for the introcliiction of thle s -'ore s by theo sprayirng method.


T1i~ i comparatively y~a clhe& a. .L41. 1:..it insocticico~ which


cost appro;iatcly t'.'ient-five.c ents peir; trc ro to spray,


.sst Ia.ural :thocs. ,.


I inow come to the m'ost important part of my talk thiso .


af'ornoon, the part to w-hich all that I have said before is an


introduction. After studying the Irootion rather a refull y,


,'e lay satea th tho. roacon for the tarlinese ,'A


natural mnethoda for the control of inecots peGss ae las'ly u1 e o


to artificial conditions.


Tn the first placec, thi'e introduce o. o. f the natural


methods for the otrd'l of insect pest :Li .a "ry lar;" dimi-







manmifacturers Tiitust pierce ig no, th a e rv:ntsc a]" divrt


attention from tho...use of'natural enemiea He .t' :",.:e it a


point to I:kp preeminently before the "oulcd-bo apr;i:",". .Tac0hi:eo







-11-


purchaser the various .difficulties and failures that occur


from the iuse of the natural enomies. J / C /3

4, / eA. In-the second place, the use 0i the natural methods


would in a large measure tbh6 insecticide business ss


*"= t8t Consequently every r.ianufaturor of insecticides


and his agents must -t-ey up the -&parent failures and disad-


vantages thiat occur from the natural mheithod 'ae orp osiZe


t-^ pretty strongly Ief2e man who is a~ep6 tingit use the natural


methods for the control of insects.


Lastly and by no means 0last, is the natural a-nathy wr.ith


which 'e are affected. The horticulturist natural pute off

t Lrting his treos Either for incsets 'r fun .us diseases until


it becomoa imperative. He then ha to ;use the means at hand, and


such means as give results quickly, Frequently he has delayed

so long 'that.'to ma]:e. : an anplicatioil the natural would


mean a total loso di ifis crop for that ear,. OCCncequentl


.oc,.thing must be done immediately. Artificial r.ieaus a:-e there;,

for the only. methods to: which he has. coursee, : .


Again this whole line of work is a new and unchartereod.





-12-.



- di .. It requires definite and very careful attention to details,


both froin the in-vccti.. ato: 's atandpoint and alo fro'i the stand-


"oinT of the orchardist. The natural lines must be stud'ie. and


understood. rhen.the iiv stigator lha dasldrtained what the lines


are, the orclhardit must familiarize himself 1 .'ith the conditions


neces,-ary for success, all of which reouiroo a considerable amount


of outlay in the eway of brain awork, a lino which all of us would


like to avoid if ,possible.


S The fi l is not an invit n-g -on for the young onto-


nologist. Tp take it'up he must beo =Scalous enthusiast, and a


man who is illijj to study umn his oi- Cot under all.c ondittion.


. Secticide, which


.n,; simple that


.sequiontly it is


the average .man


way of getting a


h'e can e certain that


chine n r has he dis-


a formula for a neit in-

't . . .. '
w"olo Hat te r is' so :-plain


ystertions 'about, it, on -


amount,- of crodrocnce. from

LIe rysteiousL a]d -cubibe Eou
me nyste-i-ous an1d oumboratmo





- I/ /] Y ^ "~e 'L-"





Il
4--l-I lzi Ito
0 ;v /h~~c,~ /~xe~~ /acxcka~~~~
;/L:aLLk'h ^ AV-^^ -^^^ ^6 ^^^O^- ^-b^r~l /^?-Z>- ^(^ ^^ -^ ^<-^C^^ /
.Z.t ^ ~~ -1"5""

I ~ rf~ J, ^ .(
;.~ ^2^2^LC ^^^^Kcc~9/' s

^^U^~ ^^^, ^L v-f^tj'a^q L



MISSING IMAGE

Material Information

Title:
Scale insects and whitefly control by natural means.
Series Title:
Writings and Speeches 1891-1920
Physical Description:
Unknown
Physical Location:
Box: 3
Divider: Articles, Speeches and Other Writings
Folder: Scale insects and whitefly control by natural means.

Subjects

Subjects / Keywords:
Agricultural extension work -- Florida.
Agriculture -- Florida -- Experimentation.
Agriculture -- Study and teaching -- Brazil -- Minas Gerais.
Agriculture -- Study and teaching -- Florida.
Citrus fruit industry -- Brazil.
Leprosy -- Research -- Brazil.
Minas Gerais (Brazil) -- Rural conditions.
Escola Superior de Agricultura e Veterinaria do Estado de Minas Gerais.
Florida Cooperative Extension Service.
University of Florida. Agricultural Experiment Station.
University of Florida. Herbarium.

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Source Institution:
University of Florida
Rights Management:
All applicable rights reserved by the source institution and holding location.
System ID:
AA00000206:00104

MISSING IMAGE

Material Information

Title:
Scale insects and whitefly control by natural means.
Series Title:
Writings and Speeches 1891-1920
Physical Description:
Unknown
Physical Location:
Box: 3
Divider: Articles, Speeches and Other Writings
Folder: Scale insects and whitefly control by natural means.

Subjects

Subjects / Keywords:
Agricultural extension work -- Florida.
Agriculture -- Florida -- Experimentation.
Agriculture -- Study and teaching -- Brazil -- Minas Gerais.
Agriculture -- Study and teaching -- Florida.
Citrus fruit industry -- Brazil.
Leprosy -- Research -- Brazil.
Minas Gerais (Brazil) -- Rural conditions.
Escola Superior de Agricultura e Veterinaria do Estado de Minas Gerais.
Florida Cooperative Extension Service.
University of Florida. Agricultural Experiment Station.
University of Florida. Herbarium.

Record Information

Source Institution:
University of Florida
Rights Management:
All applicable rights reserved by the source institution and holding location.
System ID:
AA00000206:00104

Full Text





JALE I1TSEOT3 ALu ZiHIrEFLY Q01IROL BY fATUZAL JEAlS




I: .' at jiuction.


"Small flo~ls ihavo lessor flec u:on thlir

backs to bito tf! m. TLo.e ::lo cSor fls have still

anallor onoo and thZu .. finitu.."

Unier iia'-o..;-'.l condition; no o.. spcoio.

of incoct post u ll ol to becono ox:ooptio2i a.lg

abundCiant. Outbreals do occur from: timeo to tino ap-

,parontl :ithou~ t rOacon or cause. Still wh0n tO

relationhlip of' aoe ai.. el'fcci ic stui.iol cOareouizill

one fincLs that for oor uzo raLson Luniatural oolditions

prevail in thae inr.c.diaLto neiohInorhoo. An ils-

ctration of this hind abo, !o cited. in tho Colorado

potato boeotol, v;l-.i i n ito nLtiv o lian s is, cop-





int0yc1i01ctionfI of the potato plant iLnto lar1 o rcion:,

as ocnrrec in tc e o'.!c t drin t.o covntio of toJ

la.t century, thiLJ potato bctc incroc(lC 2 0 noruou0 f

in nas2r. c. ,11s 0:iou:ht thi potat, o "eootle into


controlling OOc.ot; of 0 potato oo;to. During
Lthe early 1 Oars. it b 2co' a pot of vry 0 Cri' a

tho o1 2;l ., 'S., it 1ccoo.io t o I- r; n n...





-2


importance to the agricultural people froL. t:oe


Pocky mountains east;wards. Especially- serious was


this post in the e"isscisippi Valley. After co-.ibatting


it for a time by artificial moans, ccpecially by


the means of Paris Groen and .ondon liurple, the pota-


to beetle has largely disappeared in the potato


fields, andi since potato growiio ; has become a iocts


Luniversal in'that seootion of the country the oneuies


of the potato beetle have become almost as tyhorou -lly


established as the beetle itself.


Another illustration, .ich ray 1be taLen


front o-ur irn edcliate section, is .that of uhe San Jose


scale. It is only a little over two dcadle since


nhis pest was int ce into the orchards of the


TTnited .Stat c s. At first its devas station. ?oro almost


complete, later people began to doubt the o-eriousness


of the outbreak and still more recently, the San Jose








scale has not been considered a -corio s .enony in lhe


1i~jid portion of the southern states, especially in


the gulf togion. Where peach trees are planted in


e=tensive orchards, it becomes a pe t tht ha to


be reckoned with. Still it is not considered an unsur-


mountable difficulty, even if the- San Joec scale


does appear. DuLring the early years of citrus cul-


ture in Florida, the uo,;t serious of the orchard pcct


known wero the variousue -upcie of scale ins.ct.


At the present time, no citrus grower considerCC it


at all l:..:i.i; to find pro Cnt in t:iir groves a few


trees infoete with scale in..:Acts. As a matter of


fact, one of the most o::port, if. not the o most report


citrus grower in Florida, ihai told us cinidly on the


floor at a noting of the H7orticultural Society, that


he really wolcon-cs the pr -se:ce of one or two scaly


trees in his, grove, since if hoe ia one orT two 'aly


trees pre-e-nt, hle alwas Inons where to fird the agency








..hi.h ill. Ioe- t-he scale insoots in check iln the


1iiost economIa1 mTannior.


Prof0 :.or tQuaiintance liro0 over 3i:ty


specicos of Ihitfly .. -... l lorid(a. Only


1.three or four of th Le pooico 2 G liol.y to ovr cor n


to the notice of ti"e average horticulturist. A ll othloC


arc pra-:ctically unnon: o0 ;ptii to the 0 ytontic


onto:ologisAt. "ihoo Qpecios of ::litoiy tht a:re co:-


sic-od endoiLic by the i : eu-atic onto ,ol lo :ict rarely


or never beco::'Oc trou'blooOe to ie h'o:.- otic tillt.rict, n-ot


bccucv:e c nKiPr i vi arc; c oCf>ootod i;y t iho:. 'but oecaT se


fthe Oalanc which nac2ture 0ac atruc: 1bot ci : vai oKu

inldividual spocico in her cataloe i uc to 0 0op



thcce liitoilie perfootly u'lnd coLntr:ol.


By 1r122in27 2rovh u1e 0it 07 vroo ii oC


:~0: 0 to cultiv,-tol;V c-; ..- cill o-" i ,o ftn-".L.


tr~Oc ve arlo a oncO truck b. tlo lIr "a :I:.)r ol1


". ccioe t~-. ar not -iativ to the p.rticulr r.i.on in





,-r-



which they do their naLilnou damage. As a -ule the


cpocies of inset- pes s, n 'h1n ir" t ii tro '-O ceLd in-o a


region, increLo prodiously in i number, bocooming so


&bunli:an2t tiat t lcy are a&parUcntly G'oin;l to devantato thec
.., . I u0 "-


enotire innductry. Artificial eo .:c of roprocsioni arc


generally adopted ;,ith va.ryin: reosnlt:_ in of 'cion.y


and rofit. Later those inrct posL ...7 beco, "..ot


omniprocont in the region. Later thle.- decline in aln-


dalcl alnd finally ta.l: t Lher -c lco a2n.. 02. s c"ih


d.a:iage the crops only occacionally.


Thil condition of qc--1onOecO on the part of


inocat posts is not an adaptationn of the crop to protect


th'omslveo against the particular insct pooto, bt


ratcr a striking of the balalnc by nature to oc p those


ovr.:holar.inr: nIbocrs in check,





-o-

San JoSo 3oale.



Tho otU~il; of the la:.. of0 intor-.-rela2tion


bjoucon the ab nd:.iance o spOcio aniL the Lt natural sr-


roiiniin;S- is Za vory conllicatod problo. 3o 11any


f-actorc cone in to vcry the rounlj c thct inih tile


iucCt 0O c0ojn.c,1 ..u oc l tOy -L', c.ciin.t1t in , t2-I iT, 'uo


corrXct appreciationn of the coneriionr2. Ly 0ornin{


inl this : cmt,.r Jill 2be no ,l orC lar r7 tL 0i,' a


specific o;ail. 3y revrtin to the o-untbroal of th


Sa. Jo o i scale ...icE. occ;.r'-d LjOi't t;onty o,-o'


ago, "o will have a good illu traction. The p)roa:o.c of


thia scalo vUJ folcnd at aouit t. sL:.o -i .. 0e O to occuz


ti. tl poa c u c ardc of Virgin> a To e, rliest re-


ports th.at : ha"'v of the iSan ,occ cle oc..-rigi in


Plorila, cauro i'roir io the vo.;to:n Iost portionC of; thO


Stat;. Peoacth oro:in: hai a o cn conciicti c in thre for.





ovcry re .hat it cOIl. '3o 1lurch.egi. ?ih t2rc
C'JC.:i;i';C. L~C :CIUJ ~L Jili7l I v I J_ LU111 -rCC




'p
-7-


seeoed to thrive for a number of years. As a matter


of fact, the region w~i. heralded as being particularly


adapted to the growing of this crop. It wase thought


that the climate was so mild and favorable to the


peach tree that it would. be impossible for any enemy


to affoot it. After a very few years of unprocedoented
I .
development in the peach gro.,'i g area, the trees began


to rimyst rio-usly blight and die. Investigations showed


at once that the trouble was duo entirely to the pro-


scnce of the San Jose scale. The early poach grov'ers


had suicceeode in producing a number of orchards'


entirely free from these poets. Later more aggressive


orchardiste gathered their nursery stocl; from all


quarters of the United States to plant in this section,


Unfortunately some of this stock came from sections


infested with the San Jose scale. This introduced


into the region a "lot of insects. These in turn flour-


ished in a way that was quite unprecedented in other









part of the United StateS, (lio o tho f`act Irr-ol'


at ther 1ac pr1act;ically only oune C1onth of ho entire -


ye0r dirini hiclh theiir rLapid growth concod, this wL1,.jr


vory .atrially to the m...al rato of in4crcaSc. -Ator.


tlie San JOG0 Dcalo f-lr:itieio(;l irn tha' regiolo for a


inltlo bi O of0 GE' aIl, o an .ar i) ... a i. 1o c a2 con-


si>orable proportion of the poach trooo o0t out, it





thle mnuber of caloo pre10en. -. ctigationu 3h; o ;:c C


that paZh orcharZ pear orchards, and plum orchard,


that hadL boon "ticly in t and even onc ructoL


aith an Joc3 2al the ar b.1foro eVoro foClnd ion 1CD5


coi~plotcoly fro from the post.



Discovery of San jo e oalo ~c.ngu.n.


This very irnificant fact ro.i...d ..noticod


.otirol b.y the average ozrch.rict. It .as acrib1d to

cL, cosl .nto Li ':.i r, or .any o' e.r o nsG itio


that might haon ti o orit. To t.he sLciL tiu t, ,hoovcr,









the phenonena was of greoatst importance. It required


however fully a year of diligent and painstaking


study before the real cause for the mortality among


the scale pests could be definitely determined. The


steps -or roving tiat a c eraien aent ac 'e .c'e for


the mortality had to be tak:on vwith the Groeatocaro. And


even after the Tatter had boon proven 1:iost conclusively


from the scientific standpoint, it had to be domonutrated


over again to be certain that no error had crept into the


v/ork at any point. A UeCond y ear.elapsed, thoreforo,


before definite public announcement could be made.


Life History Study.


After the fungus enemy of the San Jose Scale


had been definitely discovered and unquestionably iden-


tified, considerable time was required to work out its


life history. The work along this line at thbt time


vats seriously handicapped by the lackd of information in









regard to methods of proceeding for the determination


of the life history of this kind of fungi. Practically


all the steps passed over new ground and had to be


worked out upon new media and by new processes. 'ortu-


nately the work was done so thoroughly that after a


lapse of over fifteen years no essential detail has had.


to be corrected.


Recessi-u for Teaching.


The first thought that comes to one, is that ai'ter


a discovery of this kind had boon made, that all that


would 'be necessary would be to make the bare announce-


ment of the fact, and then everyone would hail with de-


light the new i:an ; -.t ion. Fort-unauely or unfortunately,


however, the facts of the case are that fruit growers as


well as other agriculturists are likely to accept noc.


ideas with a groat deal of incredulity. It therefore


happened that it required years of teaching of the






-11-


facts and a continual repetition of the story to induce


even a samll proportion of the population interested to


accept the evidence as fact. As much as ton years later,


we find one of the most aggressive peach growers in the


State, saying that it required a great deal of courage on


his part to try the experiment of using the fungus cEnci.


of this San Jose scale for treating the pests. This too,


in spite of the fact that he had been, or should have


been perfectly familiar with all that had been written


on the subject. Even to the proesnt day, ie find scores


of peach growers who still consider this method of treat-


ing the 3an Jose scale as an eoperieont, in spite of


the fact, that one man alone in Florida has supplied this


friendly fungus and treated ten thousand acres for San Jose


scale within the last three or four years. In addition


to supplying the fungus, this person has guaranteed


that the f .ius will destroy the San Jose scale in the

orchard in which it is applied, and so far has not been





-12-


called upon to make good his guarantee. Fungus material


has been supplied by this one :..: alone to Georgia,


Alabama, I.ississippi, Louisiana and Texas for the treat-.


ment of San Jose scale in orchards. In all of these


states, this one remedy works decidedly well. In Georgia


alone as many as sixty thousand trees have been treated


in this way.


Treatment of h'itefly with .utngus.


I now come to a more recent discovery and one


that has been given less general attention probably than


the use of fungi for the treatment of scale insects. The


treatment of scale insects has been so generally adopted


in the citrus groves of 'lorida that scores of spraying


machines are now idle and rusting where formerly they


were polished by use. The use of the fungi for the control


Of the whitefly has not been given the thorough study


that it deserves until within the last four or five years.





-1:-


So little attention had been paid to this matter that


the sore form of one of the most effective fungi was actual


ly unknown until about a year ago. I merely mention this


to show how hastily andi unsystenlaticly the work has been


carried on. In spite of all this, we still have secured


a very large fund of valuable information by the way of


observations. During the last two years, one man alone,


who has made it his businos- to apply these fungi in a


commercial way has sprayed 750,000 to 800,000 trees for


other people. This is the correct way in which the work


should be taken up putting the work in the hands of an


experienced man. Thl' work will then be done much more


efficiently and thoroughly than where every citrus grower


attempted to work for himself. ir. Sterling of Deland


who has undertaken this work on a commercial basis charges


two cents per troo for the introduction of the spores by


the spraying method. This is comparatively cheap as against





-14-


insecticides u which cost approximately twenty-five cents


per tree to spray.


The Tntural Methods.


1 now come to the most imLportant part of my


talk this afternoon, the part to which all that I have


said before is an introduction. After studying the


question rather carefully, we :-ay state that the reason for


the tardiness in adopting the natural methods for the con-


trol of insect pests are largely due to artificial con-


ditions.


In the first place, the introduction of the


natural methods for the control of insect pests means


a very largo diminution in the number of spraying machines


that will be needed in the work, consequently every agent


of the spraying machine manufacturers must perforce ignore


the advantages and divert the attention from the use of


natural enemies toward artificial means. He must make it


a point to keep preeminently before the would-bo spraying





-15-


machine purchaser the various difficulties and failures


that occur f -o-L the use of the natural enemies. no ig-


noros these difficulties or assails those to the use of the


other follows machine vheon allied to insecticides.


In the second place, the use of the natural


methods would in a laoe measure reduce the insecticide


business. Consequently every nanufacL, ~ ror of insecti-


cides and his agents :ust hunt up the apparent failures


and disadvantages that occur from the natural methods.


These they must emphasize pretty strongly to men who are


expecting to use the natural methods for the control of


insects.


Lastly and by no means least, is the natural


apathy with which we are affected. The horticulturist


naturally puts off treating his trees either for insects

gr fungus diseases until it becomes imperative. lie then


has to use the means at hand, and such means as give


results quickly. frequently he has delayed so long





.- -16-



that to make an application of the natural remedy would


mean a total loss of his crop for that year. Consequently


something must bo done immediately. Artificial means are


therefor the only methods to ,which he has recourse.


A ain this whole line of work is a new and


unchartered one. It requires definite and very careful


attention to details, both from the investigator's stand-


point and also from the standpoint of the orchardist. The


natural lines must be studied and understood. VWhen the


investigator has ascertained whalt the lines are, the


orchardist must familiarize himself with the conditions


necessary for success, all of which requires a consid-


erable amount of outlay in the wa7y of brain work, a line


which all of us would like to avoid if possible.


The field is not an inviting one for the young


entomologist. He will not. get results quic and his


principal is likely to expect himr to "make good soon".





5' .

He will find that it is easier to get a hundred


dollars to spend in applying the "club" method than to get


ten dollars to apply the natural method. Then too the


scientists and their assistants have all been trained along


the insecticide route. The principal studies on the


natural control of these posts have been made as side- issues.

(E.G. Webbers Studies; i.awcetts Studies, Rolfs Studios.)











-v -:*;
.7.4'

'4.


IntrQucttidon. /Small floac have les or fleoac uon


their baols i them. These leuser floas have still smaller*

ones a --D t~.~. -mfrr t and thus WZ ad finitum. Under natural

cotditiohs, no one species of insect -est isE ihely to became

ez-ccptionally abundant. Outbreaks do occur from time to tinme

apparently-\vitho.ut reason or cause. Stil2 Wvhen the relationship

of cause and effect is studied carefully, one finds that for some

reason unnatural conditions prevail in tie iI:,ediate neighborhood.

An illjctration of this -ind nay be cited: in the 'olorada /orato

e'lce, rhich in native haunts is comparatively spoa]ingK-a

rather rare specimen. Under unnatural conditions, however,

ouch as t inoduction of the potato -,lant int large regions,

ao. occurred in the west dc,-ing the sovent'ies of t le last century, .
increased o,
this potato beetle normously in numbers. This brought the -.
A,.
Potato beetle into a rew region and a region f'rer from the o .."

natural controlling elemGnts of the. -'otato bottle T-eae. Durig '

the early years, it became a pest of very scorious importance to .

the agricultural people from the roc l y mountains eastwvards. Es-ec-.'

ially various va.s this pest in the Tin:..issir:'i .Valley. ..-B-. ,:,

After combatting it for a time by artificial ucans, especially .

by the roe.rns of Paris Green and London "urple, the potato beetle
and '
has largely disappeared in'the potato fields ince potato'- gro-*'"i:..v:'!4

ing has become alosost universal in thtat section of the oountr., ." ..'..:

the one.iice of the potato beetle havo becon:o almost as thor~ou ly: )'2iI

established ta. the beetle itself.
.. . .-.o~ .-*., :.' ;


rv~









Another illustrattion, which nay be taken fron our

iirodiatoe section, is that of the San Jose scale. It is only abh==t

decades sirnce this -est was t introced into the ohards of

the United States, At first its devastation w:as almost co.i.pleto,

later people began to Loubt the ;-rioe"nlc,' of the outbreak and

still more rcenortly, the San Jos:e ucale h u not boon considered

a, serious enemy in the hulid portion of t0te southern states, c-;-

pecially in the gulf region. .eWhera peach trecs arc Bo in e:x-

tensive orchards, it becon ic a pest that has to be reckoned with.

Still it is not considered an unsurmountable diffLicutlty, even

if the San Jose scale does' PPpemr.

During the early years of citrus culture in Florida,

the most serious of the orchard posts nown were the various

species of scale insects. At the project time, no citrus

grower considers it at all alarming to nind proe.cnt in their grovo~

a foe7 trces- scale insects, Ao a matter of fact, one

of the 1-most expert, if not the onst o;e:-ort citrus grower in

Florida, has told us candidly on the floor at a meeting of the

Horticultural Society, that he really welcomes the presence of one

or two scaly trees in his grove, since if he has one or two scaly

trees present, he always knows where to find the agency which ':ill

keep the scale insects in check in the most economical marner.

Professor Quaintance lists over si::ty Na -species

of whitefly as growing in Florida. Only throc or four of these

species are likely to over come to the notice of the average horticul-

,turists -' i-R. All others are practicaaly unkrnou-n o:ce ting

to the systematic entomologist. Those species of whitefly that are

considered endemic 1i 1 tt- -by the systematic entomologist rarely

c' o r
--. * ..




J..





Sor never become troublesome to the horticulturist, not because

Shdeuic plants are unaffected by there. but because the balance shich


*' nature has struck between various indilviclu.l cpeciec in her ca-talogue


is such as to keep tLm cd.i whitefl 4 I perfectly undor


control.

By running throu-_h the list of serious insect rests to

cultivated crops, especially of the fruit trees, se are .t once

struck by the large numbor of species that sAo not rative to the


particular region in "which they do their ranimum ilraage. As a rule

the species of insect pests, .h]a.introiducei into a region, incrccaos


prodigously in rn.mlbor, becoming so .abuniLant that they are a-prlint;-


going to devastate the entire industry. Artificial neans of rrepresion


are generally adoplaed with varying results in efficiency and -profit.

Later these insect pets ,may become almost in the


region. -Later they declinc.. in abundance and finally.- m=zE d a


among peets r:hich damage the cropsionly occaEionally.

This condition n the p.'rt of insect -osts
off
is not an adaptation of the crop to protect themselves against/, d*


: '" insect pests, but rather a striking of the balhnce by nature to

e'ep thocce overwhol ming number in choch'









The study of the lavw of inter-rclation Let'ween the


abundance of species and the natural surroundings is a very cormli-


oated problem. So many factors coue in to vary the results th..t


much time must be consEudln geettin a correct arp)reciation of


the conditions. I.y meaning in this niat-ter will be made more:.cloar


by taking a specific e-xample. By reverting to the outbroea: of the


San Jose scale which occurred about t'.'nty ycc.sr ago, -o w./ill have


a good illustration. The pr-sence of this sccl a fo. ondc at


about the sane time to occur in the peach orchards of Virinia. The


earliest reports that v:e have of the San Jose sale occurring in


Plorida, cane from the western miost portions of the iStte. Pcach


growing had boon conducted in there for a nunbe- of years. nursery


Stock wasAfrom everywhere "chat it could be a The trees


cormed to thrive for-: number of years. As .a matter of fact, the


region rw.-: heralded ac being particularly adapted to the gro'.'.in.


of this crop. It was thought that the climate .Uac .:0o iild ahnI


favorable to the peach tree that it would be imos:ible for any


unemy to affect it. After a very few years- of unprecedented


development in the peach -rowving the tr'70-s began to DnysEl rolusiy


blight and ie. Investigations s '-'wcd at once that the trouble va






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due alely to the presence of the San Jose scale.. The


Early peach growers had succeeded in producing a niunbcr of


orchards entirely free front this posts. Zater more art.ressive

orchvrdists r .thored their nursery stoelk front all quarters of the


United States to plant in this section. Unfortunately some of


this stock came from sections infested ::ith the San Jose scale,


This introduced into tho region a lot of insects. Thee in




turn flourished in.& nay that was quite unprecedented in other


parts of the United States, due to the fact largely that there was


practically only one month of the entire year during which their


rapid growth closed, thus adding very materially to the annual


tate of increase. After the San-Jose scale flourished in that


region for a number of years, and after it had killed off a

considerable proportion of the peach trees set out, it nae noticed


that there was a distinct diminution in the number of 'scales present.


Investigations showed that ',each orchards, pear orchards and plum


orchards, that had been thickly infested and evcefra-Ei encr ted


with San Jose scale the year before werr found co-tpletoly free from
wi




i






the -nest i-n the -.r.-t -


D.*cod; S. 9A

This very significant fact ronained unnoticed entirely


by tho avorrgrg orchardist. It was ascribed merely to luck,


cold winter, nild winter, or any other condition that might happen


to crist. To the soientistE, however, the phenomena was of


greatest importance. It required however fully a year of dili-


gent aind aintkistakingstudy before the real cause for the mor-


tality among the scale pests could be definitely determined.


The steps for proving that a certain agent was the cause for the

mortality had to be taken with the greatest care. And even


after the matter had bden proven most conclusively from the


scientific standpoint, it had to be demonstrated over again to

be certain that no error had crept into the work at any point.


A second year elapsed, therefore, before definite public announce-

ment could be made.


Life History Study.

After he fungus enemy of the San Jose scale had been definitely





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discovered and unquestionably identified, considerable time was


required to work out 4~e. life history t' at;ir ~,i-n i. The

work along this line at that-timr was iQ j iy handicapped by


the lack of information in regard ti methods of proceeding for


the determination of the life history' of -fungi. Prac-


tically all the steps passed over had to be worked
A

out upon new media and by new process. Fortunately the work


was done t'o thoroughly that after a lapse of over fifteen years


no ecential detail has had to be corrected.


Ilecessityf Ieaching t%.


The first thought that comes to one, is that after a


discovery of this kind had been made, that all that would be


necessary would be to make the bare announcement of the feet,


and then everyone would hail with delight the new information.


.Fortunately or unfortunately, however, the facts of the case are


that fruit growers as well as other agriculturists are likely to


accept new ideas with a great deal of incredulity. It therefore


happened that it required .years of teaching of the facts and a


continual repitition of the story to induce even a small pro-





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portion of the population interested to accept the evidence as


f&ct. As much as ten years later, we find one of the most


ag.-reas-ive peach growers in the State, saying -chat it required


a great deal of courage on hic part to try the er.periment of


using the fungus enemy of this San Jose scale for treating the


pests. This too, in spite of the fact that he had been, or should


have been perfectly fT.milia-- with all that had been written on the


subject. Even to the present day, we find scores of peach


growers who still consider this method of treating the San Jose


scale ac an experiment, in spite of the fact, that one man alone in


Florida has supplied th ~f us o-3y and treated t tn thousand


across for San Joce scotle within the last thrre- or four yecrs.


In addition to supply the fun.--us this pcercon ha guaranteed tzhat the


fungus will destro;- the San Joce scale in the or'c e.r in whichh it is


applied, and so far hac not been -~ to imahe o ood his gusEiran-
.f fidn-1-e
teei o c a h




Fungu materiel has been supplied- by this one man alone to Georgia,


Alabama, T'icissiE:issi and Louisiana and Texas for the treatment





~Q~z "Ii//~ t~~ -~cc1~C.-C

~~;, 1I~L-CI










of San Jose scale in orchards. In all of these states, tise one


remedy works decidedly well. In Georgia alone a i uany as sixty


thousand trees have been treated in this way.



Treatment'of Whitefly. with FungusE


I now cone to a mere recent discovery and one that has


been given les' general attention probably than the use of fuini-

.f-~i for the. treatment of ccale insects by ne- of para itic

fungi has taken 90trong a 1 Id on t lhorii Cit s gr le

that we find a ores :rnd iu'- r a oy em- oying + dsEneth d

in preferen to t roe C:p n) e7e itd satisf ory awe b

means of prying o tions. The use of the fun-i for the control

o-T 7o ~ vh itefly not been given the thorough study that it

deserves until within the last four or five years. So little

attention had been paid to this matter that the spore of one

of the most effective fungi was actually unknown until about a

year ago, I merely mention this to aJo how haIt and unsystem-

aticthe work has been carried on. In spite of all this, we still

have secured a very large fund of valuable information the way

of observations. During the last two years, one man alone, vwho

has made it his businos:.. to a these fungi in a comr.ord~~

way, has sprayed a aa e. tmees for other people. This is

the correct way in which the "'ork should be a taken up putting

the v.ork in the hands of an exp.orienod i.:. *.. ''The work vill then





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be done much more efficiently and. thoroughly than C evcry :Qitus

gro'wer attempted to ',orl: for hiucelf. Mr. Sterling of DeLand w7ho hias

undertaken this work on a cor :orCcia.l basai charges tv'.o centC p:cr


tree for the introduction of the Esores by thre sraying method.


This i2 comparatively ~ g cheap a:: against insecticid l which


cost aCpproximately t\'ent-'-five cents per trre to spray.


Bsst Hatufal- liethods.


I nov come to the most impiortent part of imy tall this


afternoon, the part to ..'hich all that I have caid before i- an


introduction. After studying the itn.e:tion 21rathe r carefully,


'0 Liay state that the reaonr for the tarjinea zr !


natural uilethodU for the control of insects pesC.c Par- largely due


to artificial conditions.


Tn the fir' t )!laco, the intr uducti-l of the natural


methods for the control of insect p-iets means a very large diii-


nution in the number of spraying machines that will be needed


in the work, consequently eve:-y agent of the spraying r11achine


.manufacturers must perforce ignore the adva.ntagec and dLivort


attentionn from the use of natural enemiesiio e mT t make it a


point to Lhcop preer.inently before the vwould-bc r .e-r;'ing: machine




I


-11-


puretaser the various difficulties and failures that occur

..from the uso of the natural enemies. / -- -


&'tR- In the second place, tho use- oW the natural Kaethods

would in a large measure ia:tlhe insecticide busincoss -ae

C'hs Consequently every manufL.ctUrer of insecticides

and his agents uust say up the apparent failures ancl disad-

vantages that occur from the natural irmIdthoo brec c ize

te pretty strongly m~ue nan who is eXpecting'to use the natural

methods for the control of inZjcts.

Lastly and by no means last, io tho natural anathy ritli

which '.- are affected. The horticulturist natural ruts. off

treating his treco either for insects or fungus diacascs until

it becomes imperative. He then has to use the neans at hand, and

such means as give results vruiclly; Frequently he has delayed

so long that to make.. an application df the natural EZav; would

mean a total los. of his crop for that year. Consequently

something must be done iuaodiately-. Artificial means are there-

for the only methods to which he has recourse..

Again this whole line of work is a nowi and uncharterci





0 -1 2-



S.die, It requires definite and very careful attention to details,


.jt' both from the invoesti-gc'to: 's standpoint and! also from the stand-


,oint of the orchardist. The natural lines must be studied and


understood. When the inv stigator has ascertained what tlhe lines


are, the orchardiot must familiarize himselff -.itlh the conditions


necessary for success, all of which rei-uiroc considerable amount


of outlay in the viay of brain .'or-:k, a 4ine -;,hich all of us would


li]:e to avoid if -;.oE:ible.


The f cld is not an invit~f"ng onoe for the young onto-

nologict. Tp take it up he must be zealous enthusiast, and a


maan who is will g to study up his !:ro oct under all conditions,


and if his work ha bh-'i done thoro ,hly he can 'e ortain thrt


he h6as not discovered a new patent ble machine nr has he dis-

covered a new cop-bi tions of chemical a formula for a new in-


Secticide, ,,which beoar. his nae. Tbhe iole Lmattpr is so plain r


Sand simple that the. is nothing of t mysterious about. it, Con-

:. soquent'ly .it is not li Ply to-receive he amount of credence from


.the average man-that .on, be given to s me mysterious and cumbberame


; ay of getting at .'the mat er,
; t............. .. . ... *
: ",. .- .,.-,_ _.,. :,. '.:. ... ., : ":. ".L -. Aa ^^








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