CIHM Microfiche Series (■Monographs) ICIMH Collection de microfiches (monographies) Canadian Instituta for Historical Microraproduetiont / Institut Canadian da microraproductions historiquaa 1994 Tachnical and BiMiographic Notm / NotM tKhnMiuti at bibliograpliiqiMS Tha Inttituta has anamptad to obtain tha bast original copy availabia for filming. Faaturas of this copy «vhich may ba biWiographically uniqua, which may aHw any of tlia imagas in tha raproduction, or which may significantly changa tha usual mathod of filming, arc chacfced balow. 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Las details da cat axamplaira qui sont paut-4tra uniquas du point da vi.« MMiographiqua, qui pauvant modif iar una imaga raproduHa. ou qui pauvant axigar una modification dans la mMioda normala da f ilmage sont indiquis ci-dassous. □ Colourad pagas/ Pagas da coulaur □ Pagas damagad/ Pages andommagias □ Pagas restored and/or laminated/ Pages restaurias at/ou pellicultes 0 Pagas discolourad. stained or foxed/ Pagas dicolories. tacheties ou piquees □ Pages detached/ Pages ditachies 0Showthrough/ Transparence 0 Quality of print varies/ Qualite in«gala de I'impression □ Continuous peginetion/ Pagination continue □ Includes index(es)/ Comprend un (des) index Title on header taken from:/ Le titre da I'cn-tCte provient: I j Title page of issue/ Page de titre de la livraison Caption of issue/ Titre de depart da la livraison Masthead/ Ganerique (periodiques) de la livraison 12X 22X 26 X 16X 20X ; XX 24X 28X J 22X Th« copy filmed h«r« hu b««n rsproduead thanks to th« ganarosity of: Library Aflrieulturt Canada L'axamplaira film4 fut raproduit grica k la ginArositA da: BibllotMqua Agrlcultura Canada Tha imagaa appaaring hmn ara tha baat qualir/ poaaibia conaidaring tha condition and lagibiiity of tha original copy and in kaaping with ttia filming contract apacificationa. Laa imagaa suivantaa ont At* raproduitas avae la plua grand aoin. eompta tanu da la condition at da la nattat* da l'axamplaira film*, at an eonformit* avac laa conditiona du eontrat da fiimaga. Original eopiaa in printad papar covara ara fflmad beginning with tha front eovar and ending on tha laat paga with a printad or iliuatratad impraa* aion, or tha back eovar whan appropriata. All othar original eopiaa ara filmad beginning on tha first page with a printad or iliuatratad impree- aion, and ending on the laat page with e printed or llluetrated impreeeion. The laat recorded frame on aech microfiche shsil contain the symbol — ^(meening "CON- TINUED"), or the symbol V (meening "END"), whichever appUee. Laa axemplairee originaux dont la eouvarture an papier eet ImprimAe sont filmte en eommen^ant par la premier plat at an tarminant soit par la damMre page qui comporte une smpreinte d'lmpreeaion ou dllluatration. soit par la second plat, seion le eea. Toua lee autres axempiairss originaux sont fiimta en eommenpant par la premiere page qui comporte une smpreinte d'lmpreeaion ou dllluatration at wt terminent pfr la demiire page qui comporte une telle empreinte. Un dee symbolea suivants apparattra sur la damiAre image de cheque microfiche, seion le cae: le symbole — »> signifie "A SUIVRE", le symbole ▼ signifie "PIN". Mapa, platae, charts, etc.. mey be filmed ar different reduction ratioa. Thoae too lerge to be entirely included in one expoeure ara filmed beginning in the upper left hand comer, left to right and top to bottom, aa many framee aa required. The following diagrama illuatrata the method: Laa cartaa. planchee. tableeux. etc.. peuvent itrm fNmde i dee taux de rMuction diff ^ents. Loraqua la document eat trap grand pour Atre reproduit en un seul cliehA. ii est film* A partir do i'angia supArieur gauche, de gauche A droite. ec de haut en baa. an pranant le nombre dlmagae nAceeaaira. Laa diagrammee suivants illuatrant la mAthode. 1 2 3 1 2 3 4 5 6 MKXocorr rbouition mr cha«t (ANSI ond ISO TEST CHART No. 2) ^ /APPLIED irvHGE I 165} Cost Main StrMt Rochester. N«« York 14609 USA (716) 482 - 0300 - Phon. (716) 283- 5989 -Fo« DOMINION OF CANADA DEPARTMENT OF ACJRICULTURE ENTOMOLOGICAL HHA.nCH C. CiOBDON H«Wm, UciMIMON ENTOMiiLOGIxr. THE HESSIAN-FLY AND THE WESTERN WHEAT-STEM SAW-FLY IN MANITOBA, SASKATCHEWAN AND ALBERTA By NORMAN CRIDDLE, Field Officer. BULLETIN No. 11 Published by direction of the Hon. MARTIN BURRELL, Minister of Aflricuitu re, Ottawa. 632. 70U 7780-1 C212 OTTAWA GOVERNMENT PRINTING iiUREAU 1915 To the Honourable The Minister of Agriculture, Ottawa. Ottawa, March 25, 1915. letin Nol! *!.Slld''fe"H^"'"'r'^ '".'■ T","; "PJ"""^"' K»tomoIoKicaI Bul- leiin i\o. II entitled The Hessian-fly and the Western Wheat-stem Saw-Hv in C nddle, F.eld Officer m ch.-.-ge of the Entomological Lal,oratory at TrtJSk" r.hiJh^ Hessian-fly is well known to farmers as a serious pe. . of cereal crops and while Its depredations m the prairie provinces have not, as yet, atta nedSe x I WlSr^nhe STTi '" "i'^'^f '"''r' °^ ^^"""^•'^ -'• *he U^itcS States, a knowluige of the methods of control under western conditions and abilitv to recognize the injury of the insect in its incipient stages will enable h.f,ners in n. c. r ^h'"'"':^ ""'' '? •* P"^'^'°"' therefore, to avoid losses that are ble \^irZ JT ^^^ '"'^'* '" P"-'^*'"*- The Hessian-fly is l,elieved to have lu' en LrS "^ ^iT ^"'"P'*' V^^J^' •"''"*•'' ^'iff'-'- 'ii'-ording to latitude and phwio- paphic conditions, etc. It has generally Uen supposed, heretofore that the insect produced a single brood only in Manitoba. Mr. Criddle's iZ^sti^itions have shown that a partial second or summer brood also occurs. '""^^ *'"«''"°'''' The Western Wheat-stem Saw-fly is an example of a native insect pre- viously hvmg m wild native grasses, that has turned its attention to ciltiV^ted grasses when these are introduced with the opening up of new countrv and thus becoming a pest by reason of the large amount of onS species of a sStable ood o this SsfctTavfh J'' '"'*"'", '"•«•''"•' "^ '^' P^"'"^ P'-"^'"'^- the attacks Of this insect have been severe during recent years, although the came of the arri^d ouU?Mr"r idrr'"'^-, ?^ ''^"l^ ''^ ^^e life-listory and SLbTts SblP tn tlf/^ \ '^'^'^ ^^^ °''''^*' It possible to recommend control measures unon inch Wnn J^ ™ provinces, as these measures must necessarily be based rtLrof'thet^lfn."*" ""''" " *'°'^"«' acquaintance with the a^gricultural in this nnhH?!?inn%*' ^^ "^^^^f of the information and illustrations contained Lnd fh.f« h! in ' ^*™T ^'" "^^^^ themselves familiar with these two pests drmiStt;r^ro^;rXYn^ " ^^'^^'^ ^"'^'^'^''^ *'^^ ^^"'^ «*^--- I have the honour to be, Sir, Your obedient servant, C. GORDON HEWITT, Dominion Entomologist. CONTENTS PAHT I. Thk IlBMUN-rLY U»ayrl,olaJt,tn,Tlur>S/A;nS!^i:,"^^ '"";"'^"" •■"••"■"•"^ ♦«•" fr...,. tlu. farmers .v.'ur iV7(i, an.i ;«s s ;\"/.^"tK ;; ;"*:;:"*; '*;'";,"'• •'^;-^- ^'^^'^' ''•-'• '»'•• N..rtl. An,<.ri,-u. It pr.,l>a hh r • .. \I.. Jl i '"' ^^•'".•••'t-K'-"«i''K "r.-a of '"■fore the y.-ar 1899. s first a. ni,. 7' ^'"'^ •'"■•";""■" '"•• "^■••'"••''•l<' in Manitoba .-stimate.! at fomurtS ,",!"'' i^r^'fVh "'''';" ''"'""«" ^^"^ •'""•■ •""■ si-<- -p-- winterinR puparia, commonly cale.l''Zv 1 ^^'' /"'•''*' "HP' '"• from over- May. . Kpgs^re depo.Sl immi^ »'"'f "f very minute, narrow" redclish Tie fan, m^^.f """^/''n/'rKo. Th.-y are (TeaHe.s on the upper surface of tCelv^s^^^F^^^^^ ""^""'t 'T'^*''' "'•'"« ^»»- 'vhich at once work the r wm rlow^^\ ♦h ?™ ^*'''^" T*'* ^"*''h ^niall mauKots they become stati,>narv. Fuih- ^Z^^r^' "^ '*"' .>'"""« P'«"»^- ^'here an, white, or Rreenish-white in co „ur ThZ ♦ '^T'"''''"^ ^'"«-'''^" "' '^^ape •luring the latter half of Zne a maTritv^/TK "■■" *" •"'?''""" ^""'« ^''•'•'"^ ) until the foUowiuK ^prini The n, nari/- '™/"T!"'"^ '" ^^""^ r-on-litio, colour, and res,.mbletu.m^ns|nVneKn?!H,fn ""\"n''ke true flax sc.is in and less flat. ^ ' ' '''' *'*'' ""'"*''■ t^ey are smaller, narr..w,.r. of Jt^eZurS;:rrof^!;i;;' ii^:^z^: p^-'^- ;- ^owams ti.,. ,.,1 month and even rarelv int, A gust ThiT*^ to appear throughout th,> latte rule, just above the second „^tth • • P."'''"at'on attacks the p!:ints. bonding of the s?emr'a?te/"S'„; .'^ , "S' '^'^'"f "'™?'=^"' t ^h.' -"""known produce flies until the followinrsn,^n' T ^"P^"^ ^^om this br„o,| do n,>t portion of the spr ng broo VnTr'^V ,T '" n""' ^P^u"^'" ^''^ ^he remaining probably a variation In tr number of S,.^^^^^^^^^ ™n,litions there i^s June the percentage being pTumaWv mucirg'"' '"™ '^' ^P""« ^^-"^ '» r IS a 8 leaves"^7mVboTei"^^^^^^^^^ P'«"*« °f*«" ''''"twining but a few aid die, though occ?8ional y Xv will «urvi the plants become yellow to one side. Puparia of this brood a^Lo/TJ by sending out fresh sprouts In the summer brood thoy may be fouid S hT ^^l 'r*' ^"'°^ ^^^ ««>»nd- joint of the stem of the Kf ""^ ^"'* ^^'''^ ^^^ break near the second Plants attacked are wheat, rye, barley, and occasionally a few grasses. Th'^Slr. .■ 'M^»I.f "'?,-i'h HheatlT .Cfv^' 8h'owiroSoar!:,^^S„T.^jJ- P^'A°' « characteristic bending of the "tern ca^d ht fc"*' """T" "5°^^ second ,Wt? 3 figures natural 8i«e. (Original) ''^^ *''* »"">'ner brood; 4, adult tfy "' All to be not k£ than 5 inches dem-inriL„?'^ i"" '^r'ng season, plomhing .11 stubble ,nd strTw pita&eeTthldS,;^^'^^^^^^ "? P«''<^<'- (2) Burn gather up .„ screening and^iriL't^fS y^T Lt^begi^ X't^ 9 ^/Sd^e '^S'V%^,t-.^^^^^^^^^^ or b„r„i„, ,, ,He proper St . hhl "^""^ ^^- /^) Sowing stripVo?g^^i«„«^»J_r^fb^^^ ?nd ploughed down stubble and newly planted grain to attract fliormoi'''^* '^''^^ '^^t^'^'^n infested of severe outbreak. The strins shm.M h« i T'^ '''' V'^"'"*"! *<> on occasions about the middle of June. 6 Prepare a Roo jt"in 'f'^""^ Ploughed diwn V.orou. Plants will be -re i ble ^ re^ira^Sf^iron^^J: ^"^^^^^^^^^ minin^iThrnumSTfSel ttrw^i^^'^ ""P'^'^-- - ^^^^ors in deter- wh.ch there is an excess of iinfaH comblE^H ' Ik ^^^ '^V^'"" ««««on. Years in summer, will favour the inSs de^do^^^^^^^^ have an exactly opposite eflfect. '"'^^'^'opment, while excessive dryness will ^ntrorS^esYlntr.^ ZVr^Zl'JSs'C'''' -^y ^« -«-t to as of minor importance and should notYn nn? ' 'however must be considered at periods of severe outbreaks '" """^ '"^^ ^' '•«-"«d upon by farmers rlpeZ%ZT:::ii:'^t 7:.Z'l?::fy-'^ f^^r^ *° -^- than ,ate- the summer brood, while barTey by beinrsow^^f! "^ might escape most of all the spring attack and yet have time to rh^l^^u *^""'' ^ ^'" ^^'^ape nearly as a general rule, though an occIsiSsP-^T ' ^^^ '''"^ ''a^ be said of rye ^ Co-operation is essential in t\T«n ^°" "^^ P^'ove unsuitable. F^ies may easily fly f^omte fiddt nIKothef in ih^^^^-^^ '"^^^^ ^^t^reaks. vation IS also of much value in enablinrplarfcsUt tttrer'*^' ""''^ '="'"- INTRODUCTION. cereaT'c^ro|s"ttr^^^^^^^ one of the worst pests to Discovered more than a hundred years a«-oo* t ^""^ i*?^ ^o contend against, since gradually made its way over the wL.^ ^""^ ^''*°^' ^^^ York, it has causing enormous los.ses in neUreverv Jace i7l?r"? f? °^ **^« continent, t has taken heavy toll from the farmers of f h! tt ^fVi''*^"^- While, however OSS at times in Eastern Canada!^ denredafVrfn^'h ^^^^t'' *"^ '^""'^^ "luS less in the western provinces and wl »i«,ff k * i'"*"^ ''^''^ been, on the whole smce the insect was^first XVved tWeri899 ^ '''''''^' "^^^^^-^^ '"f««^at^n continuous since the time of its first inf,^ J^^ P'^^sei'^c, however, has been since then far greater toll ha been Sa^Jed from ?h ^^ "" T^^^' occasions supposed. Small losses take place ne^rll I ^^^ ^^^T^^ *ban is generally weather conditions and the ahstnL f ^ ^^^-^^ y^^""' ^bich with favourable multiplied to serious pUortionr'Vuch^ofThf' T"'' P^bably'roo!^* be ''^"'ded were farmers acquaint wUhttntT.^-'"' ^r^""^'' ™'Kbt be Unti quite recentlv It «,oo . . '"^cct causing them. single broo3 in\SZ XlZ^n letVt^^^^ but a the small amount of fall wheat grown DrecripJfh *^^ "''•f ?"' combined with developing. The only attack recoJni7PH tt f *^* possibility of two broods summer and caused the broken steS in Jul v7tr'7^f, ^l""' ^^''^ ^PPeared n however, that there was an error S this dLn- f '*^"*' ^ began to be suspected, menced to make some studies of tLinLet'sTfehf?"^' '" .^^' ^^' ^"^^' "om^ once for all the facts of the case and Vufw • '!^«-b«story with a view to settling WhUe these investigations we^ part fv toTf }^ P^'^^^' P^^<^ti<'«« ^emS joining the staff of the EntolZiS%ZTfnVk'^.f not, however, unti norma, climatic eonditionstX;^ii:X"eSSot,S^^^^^^ 10 Alberta during the last five years. These seasons, however, were in manv Darts unusually dry and therefore unfavourable to the development of the flieJ. HISTORY OF INTRODUCTION INTO WESTERN CANADA TTinf V"' "^f^^'^n-^y "^^1 £■■•'* J''fi"'t<^'y recorded from Manitoba by Dr. Jame^ Fletcher dunns the year 1899'. It had, however, been reported by correspondents the previous season and, in all probability, invaded the proving with the rush of settlers some years earlier. From whence it came, or how it was introduced will remain a mystery. It could, of course, have easily been in^rodJced from the east m straw but as it was recorded in numbers Vrom Iowa, Minnesot™ and the borders of South Dakota, in 1896. there is every reason to suspect that LTnUrlVP" ^°;!"^'''''^' 'T \^' '°^'^' h«^''"« ^••^^"'^''y worked its wavwes and north from the original place of introduction in New York state Curiously enough the most .severe outbreak ever experienced in Western Canada was in 1899, the year of the insect's first authenti? appearance, and on hat occasion the at ack practically covered the whole area under wheat cron being worst in the older settlements along the Red River valley and extendSi fTom To^fo ^n ^""" ^."^' ^r\ ^^' ^««^ ^^ '^^' occasionlrsafd'o have var ed from 10 to 30 per cent; but unfortunately no trained observer was on the sDot I'n^rTh"*'^''''''* '^^^V^ ^'''^'''K ^"'- •"«*«"''«- "« '"'"ntion is made of spring mjuiy though we now know that the fly must have been present at that Sme ^!J' fV^h dark as to its prevalence the previous season, though a^ mentioned by Fletcher, it had been reported from Manitoba, these reports however, being without verification. reports, The following year as is so often the case with Hessian-fly outbreaks was practically free from in estation; in fact, no records were made of ts presence though a severe outbreak took place in Ontario. We have no further information of injury in Manitoba or westward until 1902, a period of three years At tS" date, however another rather extensive outbreak took place, beiuE Lain particularly noticeable in August, though a few observers on th's occa"bn Sso "tZViit uT-^ >njury.3 Since 1902, several minor infestaCs Lve oicSrred the attack being confined largely to young plants in eariy June. The presence ?ears pStnd t'mJ t'fo'nT>^"'*' "^^^^^^^^^ in Manitoba f'orTveral «„T* w '*"^' •" 1/13' I found It even more numerous near the borders of Saskatchewan than farther east. No thorough survey has been made of the Rr«S f^'^*"'^"**"'^ ^«?* «f Manitoba, thouih reports to the ESomological Branch from correspondents in various parts of Saskatchewan wouldTudfcate that It IS quite widely spread over that province » '"mcaie «nH 2"'"u"^''™^*'°'^,':^§f *^>"S *he insect's presence in Alberta is still more meaere and we have no reliable data of its establishment there until th^TeT; 1911 In this year several farmers complained of injury to spring wheat in the southern portion of the province, the attack being noticed '^^nAu^usfdue to the bending of the stems Specimens of infested strtw sent in for determination It least rpor?fon°ofllMh*'V *^' 'T^*' f""- ^"^ntly its distributTon otr ai least a portion of all the above-mentioned three provinces is no longer in rCLSl'ySj™"' ""' "" "'■°" »'-«-P'-'"*« area' U^Sbly EESCRIPTION smnlfer^'^*' ''!f^ '*" '''''^''' ''.Kf':-'-<'ddish, linear-cylindrical in outline, and very small, approximating one-fortieth of an inch in length. ^ daU^^di/tXuolt iCpLLe? "■"""«• "''he University of Saskatchewan. Saskatoon. Sask.. for 11 Larva.— The hrva when first hatched from the ork is seldom met ivith in th^ eSsTbv a hardenfn '*"''; tl ^"". '""V '"^ ^^^^"^ (commonly cSd '' fla™ se;Sa/m^"n?h^S"uf feed?'; '"*" ^'"' '" "^'^^ *»^^ '-^^ -">' -™-""- LIFE-HISTORY Nnr^l*nol°*r^^*'"^ \° "?*^ ***^* Webster', discussing the habits of the flv in North Dakota, remarks that " the breeding season extends from about M^y 2S ' Circular No. 70. Bureau of Entomology V. S. Dopt. of AgrieuHurc. 12 upon seasonal conditbn KgRs are de^^^^^^^ dependmR somewhat flies appear. Thev mav be foifnH^mnn^f K "^^L immediately after the their crevices/in LXrs varv?n/frnm i "f^f '"'^*'^' °^ ^«*^^*'' »»d along may be locat;d on the unde"£%r eveHn th^ •.^""•''^' '.^\«««^ whether the larvffi from these nnleJ, fht^ m «*^™«' but it seems doubtful out other sprouts. To quote from Weh»t.? "VlT. . i T?. ""^ '""'' the pl,„t head foremostYd sore matalSti beflXStarw^he?','!: ""'' "'"'" Jt:SorrseturhJ!?'^ni;'°i'r^^^^^^^ leaves about a„ inch M„tr'ir^lT„ltrv*.f„Xro„"f tter. Summer Brood.—From about 2<^ dt cent t,r th^ o™„_ u j a- mence to appear the latter n«ri , ?'L- ■ ''"""^ ''"^' "'« "om- the lOth ofJul" "hen they SSdua. ■ jTmflT"^'"f* '"."""'''ers until about oddi,,terval,uptothecSfthe«Stw«nf i,',™ .'"'■ ''°°"™,'> "PP«»rtng at Eggs from the June and lUMt of the Mv fli„ tr/' °' TT ''?" °,' ""> 'S""- above the second joint and larva Vr^Lh? f ' f ? "■"'"■ *.P<>"'«I on leaves partly h„ried in thl Sra^jurt Xve that^oin?"'?."''''''''^'' i^'V''"'*'' "'*«■' wo^uSv:i.riirs^ -E^^'^^B^ s';;Sn'g'L3!t<"'-"*"^^^^^^^ INJURY AND HOW RECOGNIZED fromtU'o1"tLvrrliU\e1ntlm7aro?s' to distinguish Hessian-fly injury The young plants, X^ SaLL h.Tttr'*'' ^l"''^ f '' «"""'"^"y associated unusual bluish tint, whife TZZ "^^1:1^^ ^2^^^^^ an low 13 shoot: inre^re^TcVits^tii^d"*"^^^^^ "' '""T' ""' *^r-« -^ "- patches of grain. m?re ofl iHhe Ker ^00^ "1?/ ^ .nfestation. large and the whole field will have an .inov^n T I' hi P^^^^'^aHy destroyed germinate. A closer in^ectbn however reveiuthe"deadln^'''".H^^^^ ^'^"''^ *« in position among the leaves below the ground ^ ^'^^ ^^"^ P"P'*"* thoug^^Uy^SikMo HeTsLrflv;ZT'- ^"^^'V^^T^y^- and O^cinis spp.). straw at this spot will alwrvs r™ eal fullv .L i ^T\'- ^xancimation of the the work is that of the HSn-fly ""^ ^'eveloped larv» or "flax seeds" if cereal';S^r "£ Yo ^fh^rdeS^Sl^r '''"'''l '''^ ""«" -'-*- below the ground among thlleavt Tear the"roots.''""' '''"^' P"P^"" ^^'"« FOOD PLANTS thoug^h^pSbt awSrr^^^^^^^ T'"^^ *^"^^^*' ^y^' -d barley, MEANS OF DISTRIBUTION puparia occur in abundance in straw tipv^ili^P' u^ ^P''^'^ b"* »« ^^e continent in packing case^lnd other .nnt^ ^^^ ^^-'^u b*" •'*''"«^ across the NATURAL ENEMIES. 14 1>""''I!^^^^^^^^^ wi,ew„™ ,„„„ i„ K„„.„, RELATION TO CLIMATIC CONDITIONS nurabors to endanger the total product and fh.?'"'"^' ^''^^ '^"^ '" ^"ffi^-i'^nt the entire crop, it suddenly decTelses to nnmn *■' 'T''*'" '•* ^PP^'^''^ to threaten There is no doubt that paras teTpav ^rr^"^'^^^ but a factor of probably still ereftfpri^/.P°'^"?* P**^ '" these reductions to be that of humidit;f comSro?oSreTtrnr f'""^ ^^°^'"-« "pp"- , An exam nation of the mpf«nr^i • i * V^'^ temperature. the period of our worst infestaTionTeteaMhr^^^^^^^^^ ^''""'^«^^' ^'--^n^ heavy snowfall during the winter of 18QS 0 tI ^""^ ^^^^ *''*''"« ^"^ «» unusually snow. The month of Mav Sucedl to i ^ ^P':'"/,^'^ 'ate, following heavy while the spring, though ^r was afte?w^rd'*f '^'"^^i '' *^""*' ^" excessive one^ ditions that are recogSized as frvouS £ th"'?'^ *'*™' P'-«viding con! From August to winter the rainLl? was verv I Jht ''"'^ITu'?""* "^ the insect, a very dry spring in 1900, continu ng untH June'^S? fi?'' *^'' ■^^'^ ^^"o^'^d bv most unfavourable to the fly and wh^h woL Z^M? 'i •"^P'"°''"""« conditions themsect to nsignificant numberrdurinT IQ^ *^ ^' instrumental in reducing prevailed during and after the outbreak of^O??' AnTh'''•^* '""'>•• conditions the effects of drought was noted during 19 4 when tX^f' '."t^resting example of npenmg of crops, thus drving ud the stem« . Yf ll^'V^ '■^'" '^^"^ed a premature and, therefore, while most of them w^rT ablT ^\ '^7k* ^'^ ^""^ developed survived to produce flies *''''' *° ^'"ter the flax-seed stage, few -specfThaf^t'sreS d^f cllSTat^pZS^ '' '''''-' ^"'^ '^^ - to Proymces will always prove a checT n ^11^^^ '" """'^t parts of the Prairie fly m large numbers. Good croDvearsh '''"*" "' Prevalence of HesW years, and so it behooves farlrt'obTo;%h'rgSdKllTr^^^^^^^^ ««°^ '^ METHODS OF CONTROL l'-^l!?J?~^^^^ in th. Middle West, with httle loss of time and smil inconvpnit^ fr ^^ accomplished, as a rule tions presented below, onlv thUrmeasures of J^^^ .^" '^' recommenda: others not considered practical, ravTrerp^tseTy'omrtt T "^ «'^^"' ^^"^ ^^^■^"^^'fthrLj^^^^^ verrfetflt are able to make way through 1 Lh whe„ the old pknts tt'-^T! "? ^'®*'"'ty in forcing ?het a KUide. As it is impossible, hotvJrto^S'f*^^^^^ ^?u^*'" P'-^^^nt to aid as furrow are equally deep, it is ^und kd?i?nhS '°'^ '° *^^t all portions of the m excess of what would be necessarv conW th ^° ,T«™™end a depth slightlv of the upper surface evenlv P/S ^}'^ '?'' ^^ turned to cover all narts ramsto All in any cracks or e.^n^ntsttri^^^^^^^^^^^^^^^ T^ZS^:^^^ ■ Bullc-lin No. m, Kansas State Agricultural roUese. 1913. 15 Thi, will d<,trov nil II " ™mm"r brLS Z,^ u ,°Vi'^ "I 'f? '°""»i"K »prin«. injure the .pririj broo I "vS it m^i^ „ - '" ''•'' !^'■ 'i'"''"''' ''"' »'" ""1 It is ah, impomint to L rov ai «""„i„f, lrZ'^"7^ 'l'"''°" ""■ S"'""'!- £.1,1* or Ma,.. o.beS'.;,7„!v onM'a^ tt''. lll^tl;;; ^^^1^1:^^ .u,fict;ttmi:il\!':SKrfflTr;s''"i;'r'r"''"™'"''- sort of co-operation is necessary in ™rTii„f reinerabcred, however, that some £:r''^hS;;%-.™ri£:£S^^^ The strip of land need not nocSr h he nlmJh "^'^'?* ^^ praeti-sed to advantage, disk drill is sufficient The ^lelTln Z P'?."Khed, either diskmR or sowing with a advanced to aUract and re ain UXs as^'theVhafeh*'"? "'•'^'!i!^ ^"^'•'-"t'^ ploughed down Sore June it^ ""''' ^' ^^°"* ^0 feet wide, and must l," diskiSJlHuIu^JtTngX'iTfe^teTs^b^^^^^^^^ '^^ '« ™P«-i'''- besides starting variourweed seeds It In f '" T^"^' °^ ^''^ '"^^^^t"' which the flies lay their eggs instead of flvinlf T""'' volunteer wheat upon this should be plougheLoKiTn June hS^nL * "^ T^ *^„t '°- ^^ P««-^ible, if it is not turned down unTil July ' ""'"^''""^ «'«« ^,11 be destroyed even be us^e?ur[n^2r„t tTi"^to™;Sa3"^^^^^^^^ are .strengthened will to begin with, that the be™ avaTlable seed is used foJtwf ^'''''a*^ !* for granted, a farmer should know from exner LpTJk . -^^^^ As to cultivation, suggest, however, deep P oughinf the Tand to be^falr V' '^"'l ^'f' ^^ ™'«ht bed by means of a harrow cdtivatnrnrn« i*^ ^""'""^^ '?*'* * K°«d seed- convenient: generallvsSTnir « firml'^ . }^''''^.u' ?^ ^^^ ^^ necessarv or to be ideal Ei^LflTattacks ar? T^'^'u "^^'^^ '"*• ''•'°-'^ '"'^^''^ '^^ considered ditions,andmorerer?wt„^ternd'^[rLt^anT^^^^^^^^^ ""^^^ -^" -- attacf:S::riralTotn^'gt^^^^^^ 'T "«* -^-»>' sometimes present in it as are also v«rin^ 'Vf ^f"^" Canada, it is nevertheless advisable to^heck such' g^wTht; cXv^tion S' fX"'''"*^' '' '' '""''''"'^ barlefrSm?nX4^rat^?k\rth?li^ '"°^"' 7.''^ ^' -»^-*' ^■-. or favourable to the devebpment of the inseoMl?n"1^' ^''"".^^ r"" "^>' ^^^ "ore would doubtless be lessTa^e to suffer from A, °*^""''k ^-ajly-maturing wheat kinds; it is very doubtfS whether tLt^nf™™^'' ^^u^^^ *^^" late-ripening on su^h varieties a^Trelude and in this^r^r^r '"^^^^ ^^^? *™^ *« '"^t"'*? advantage over Red Fife '^'P'^'^* ^''*'" Marquis would have an and ?ef Sve>ttJ. 7t"ime To'rti^ "-thi^r^.H^^^^ ^" *l^^ ^P""« ^"-^^ ordinary seasonal condition" '' '^''"'^ ^'''^ ^PP'^' *" ^y^ ""der 16 PART II. THE WESTERN WHEAT-STEM SAW-FLY (^^- » """d I) (Original). ^^ "" °' ">« '"^v*- All figures natural siie. INTRODUCTION. Agropyren, of which our common rye or whKS;.T '^ belonging to the genus Mnall economic importance, a„3 deZded fof'Sf i!,"? ""^"P''- " "" 'hen of by para.,tes, upon the number of flS„t„VleS ^^LlS We'^^uTn throuKh .limati.. ',.«»>...« w olrre uc 2 s w fc^^^^^^^^ '" ♦'": ""«''•""« -sterns r»r()(lijc."«l. Thus it HurtUHt.'; fr^m . '^"w-Hy i , proporticn to the lioa.U s.'ttlors, upH(.t th . ,«Iun rS na Z- "*'■ ^" =''''"' ""* ' '"»"'''"''' '" »»"' form of Saw-fly wa.s no lo.Jr I. -n Ij^n^^ "" that honn.for.h th. Instoa.1, all that Wtt/n..^^si y wa" forX n J t fl'l fTh"' ''•■■ •:"!'^i''»"n<-"- li far Kr..«t.T al.un.lan,.,. of fooci awa [., lit h„.?V . ' ^"^ ^H' «•■"'" «'"''''* «•'"•••«• It is interostinK to Icnow Imt evnn n th i"'' *'''7 u"^""' *'"•'" "vaihil.l... Sawfly still preferml s nSv. £l plan s ami "7 "^ '*''* .'''*'"'>' ''""''^^'^' 'h. !'n.H>Khit«.l,lomatta,.k..' '" '^^^-toba. Ue and there a few wheS stemf w?re „l ♦^'^L'''^ '";'"« '"f''^^"''' while another severe outbreak more th.Trh?-*'" attacked. In 1907, there was and, c-onsequentlv he 'S-fl erfl. w TV" «™««^^w«'^« «ble to ac^ommocbtT. .lopositinjc heir •:«;^up^ SJTn ^ r;hTch'':^^^^^ «'-T"« •'^-"• plaees. Indeed, odd fields were almost enHr^l^ ^uffored severely m somi" while tlu. injury exten.led ^vorai tlted Sinto tS'^^L"'?'^ ''"■''' '"^«^^' customary, Rradually less severe towards the eentr« «• l^' •"'5?'ninK, as is turn, the inseet seems to hav. c^hangS t-^^hab t" and ^nl ♦f'V'"« "''M"f"«t"- Krasses, ,t selects with eq.ial readiness he stem« of ll^L V*'' V^ preferrmR wild year from the old stubble to the new crop '"* ""*' '"'''''• "^'"^ *'"''h It ha;^':!^?;K,*;s,;:r;^^2;s KS^^t ^^'7f ^ ^-^v" '«««' due to its being a native and consem.enflv „ / «• ■ ^'**P'''?<'''tions, doubtless vicissitudes of dimate/ That t marnke ho wi ^^^''"nK «« «^verely from the by proper cultural methXtLre^i; no Jm.h^ ^^^^ adopted the insect may at a^tm become" a^Ve'ry' serious' pesT "^''"'^•^ '''' ORIGIN AND DISTRIBUTION. stem\"y!'[™nSnouf to No7th 'X "' •" '' 'V'^-""^™- -•'-'- ^he Grass- MarlattfromWecSs cSectedriSQO K ""^^ m^'"'.'"' ''•^' «"^^^ ''"^ The first record of its occurrence in f 'if T^^ James Fletcher collectecl adulLTv iv^en^. at T^'r'' t"™,^^^^' «^^«" ^'^ was also reported as causing in urvatlnKV*]"?''!! "''^^^°" "^"'y 5. It 1896, and fully treated of under Se name of ?J,S' ^'''^■' """^ ^^°""''' ^^I»»" *" the Entomologist and BotaS of thTn^-^"* 'i^^'"'^"*' '" the report of that vear. ooianist of the Dommion Experimental Farms for AmeS:"hi:.i:;':ptrreitly'^I ^:^^ ^-ii^ "^'^^ "^ 'Z'^ ^-^'- ^^ ^-th where native buLh graLT(l,rovpZ ^P"ng-wheat growing regions F. M. Webster' describes it afocSVn hf '^n IT'^^^T abundant. Prof. Montana, Wyoming, Colomdr Or" ^n vL^?^''"^^^ ^>,^braska, Kansas f?), Canada it has been !^;ken from alm^^^^^^ T' ^>''fornia," while in to the Rockies, and there isTttftoubt that' t'Tl ''"^'' «f .Manitoba westward British Columl,ia. We hive no records of h •" ""T"'' '" *^ '^''''' P^'^' "f is it probably that it will ever h™ ^^'' '""''''^ '"^'^^ "^ Manitoba, nor wu^^heat'lartl'U;.i\rplLl7:prin^^^^^^ '" ^'^"^ -^'-'^ -bere ' Cir-'ular No. 117, Uuroaa of Ent., V. s. l.opt. of Agric , 1010. 10 DKHCHIPTIOX ^..^\^:^:;; ut:;';SiS';?:'"""' "'*^"^^- ♦•- ^-" ^" '- -"'''y Hair lines indicate natuml si,e of L.w:flnnd„ri^otTori;?..Sl )''"*' P"'"'-""«h '■•'lan5«J. larva^"^""'^^' ^"P^ '' .K'veloped in May within tiie stub inhabited by the 20 «o. In addition, the fema 'juw ^! Z ""J^l ';•""»'«• *nd in tho malo ..ntirdy of the body, UHcd for d..S i;;';;^ ''"?i,;V'"i' ,^»J";i'^ «PJH'ndage at the ond one-third of an inch- that f th„,«„i *^'l"'^^*' '*''"'*'«•'• approximately a «ay f^om'tE: emerges as a fully developed saw-fly *towaJds the m-Hnf* Vt ^ * P"P« ^"'i of emergence, however, depends somewhit unnn f^ '^'^ °^ "^"S*- '^he date early spring, saw-flies have appeSThe fir^f ^ i,^ ^^^''- ^ith a warm they may not emerge until XiTlhl^nrofXVl^nr Se'teT^ 21 until th.. mi.l.||.. of -./..Iv .1. , « iv ,.Xn '0/ w?/ ••'"' *^;' ".^"^ """'^ *" '"- Ik- ovifH)MtinK. • »"'"'"" *" «''"<" pmo«J the f.mal.M miirlit II., . ^ • . . . . MEANS OF DISTinBUTION. »'<-"«;«th the ground, and ;Ko " ,r i.. {oMJ!':"" 'I" r'""'^ "" " '»"« m. hod whcrehv it could Iw distrih.vl • k «'^V^*' "' •''''"' ^"-"w, th.- ordv while, in tho adult stago A \ho t" " t^ ^^""''•*«'"" !'>' "^''fi'''"' '"rrSo han a f.-w milen yearly, whil " th Prhan 1" oMf . fl'"'' ""'■■' '* ""•"''' ""♦ «>' "'•T" being transported immediately t^ other ^r. 'o ,-'n "f "" *" '"■ '"*" "*'J'" '^ ""•' oincr parte o s not seem very probable. NATURAL ENEmIKS. trolledi'dlj: In'foSS'^Ziv'jhaT};/*'''' ""'! ^'"^ '^'"-«V «-">« to haye been con- records th.. rearinHv \?r G T R? P"r''*'«- P™'- ^ • W. Webster, h.mevt" the larya.. I haye aL obs^;ved n^raltif i^^ undoscribed ehalci.l specieXm the species to maturity. Parasitic mfestation, but was unable to rear EFFECTS OF CLIMATE. steml^rhrjla'^ts ut;>nXh rSse"l7elf'''H'*'^'''"T-* «^ '^^ Ao-HnR indirectly injurious to the Siwfly's deyelonmenf ^""^4^^ '^''' T^ ^ «*''« ^o he howoyer, the insect is more dirooiL^ffnnl^T \ ^^ *!"*''' «f ""'vere drought An instance of this was wulS n^9H l^^^^^^ ""'^ ^' ^^"^ ''"'^d outr"Kh .' due to drought, killed a nuS of llryl L^t P^^^V^^ "pening of wheat appears to be necessary for t he flip« f « K ' ^'"u^^ stunting many more. It actiyities, on the othe^hand are mneh ^7« f "f «h.ne while oyipositing. The r OO-F It seems probabl^'XJefo™ thaT a cold Z\'\'^' temperature^ blw di-sastrous to the insects as an unusual y d^^''i°"''^r^T ."*«*'* P"""^*^ "^ deyelopment would be a moist spr^ "kv s7nnv r„ ^^^ 'deal conditions for during July, to enable the full dSpmenT of gm'^.se" o'^ grains ""* ""'''"^•'' INJURY TO THE ^AW-FLY THROUGH CHANGE OF FOOD at leJ^tteXV^o^Vhir!? I'a^s St^Se^r "^^T '^^I'y ''^ 'burred HI which it previously fed are aKiff in Sf ''"K'"^' y- The native grasses up and down without Lv HI XSt^.^thJh"'"'/ '""''''"»^ '^' '^^^'^ *« tunnel -— - • '^ " '^^ ^^'"'f o"- rye, particularly the former t.. U. .S. rj'.n* ..I i_. .«.„ 'Circular \o. 117, Uur.-au of Ent IJ S n . ,4 ju 01 r,nt., u. S. Dcpt. of Ajr., 1910. 22 S IXs^r^aklt na"Vl:To^;^^^^ °^^' ^^ r"'^ ^-^ — ^ «f w-d or is thus o ten kUloTnthe breakinrL K **"'°^'?' '^''T V^'' '"^* '« f^^ding, it not lacing able o reach the bai of 7hp n?™.""^ Vt^^^^ ^*^°^« ^''^ ''''''ak dies by After .trL. ^^na.:^^^'^ ^ii^^^^J^^,;^^^^ home^ INJURY AND HOW RECOGNIZED. tlu.»,. ,a»-fli,.,. By oSw oSn Jhe ,?r»w, J" " "".'" "i?""''' '^e work of larva itself, which ™aybl%?trab^^^^^^^^^^ -» ^--er the much^'lonSe^ '2r LiniuTrv then''" "^^i'f ^^^ ^*^™^ -™-" ^t-ding to harvest, uilj' Zeve^^t s cut hvPfh'^l*''*'"" ""*'!, *^" «'^'« >« '•^'^^y the time considered^ Slby fa mers and i. f^ZV^^^^^^^ '? ^^^^"'^^ «f upon the ground when the harvesteTar.'i^ei ' '''■'' ^''"^^^ '^'"« ^'^''^'^'^ by nf^L'r'ell'""E:rl7i„"'ttTea^1he'^ ?' recognition determination is suggest is to split the grU .straws when "the'' h™? ''"^ 1 .t*'-'*'«° °"« ^^" revei' '. Towards the end of In?J ^k V. ^l borings of the msect will be the attack may be confSse,^ wU^tha^^ ^hen In addition to the character strctunnpllin^ I ^'^^^.f ^heat-stem Maggot, blackish near the iointsr^^l^^^SlllIg";!;? id^XyV^^^^^^^^ *-" FOOD PLANTS. u^nZt''^.^!lLfLSr:Z Wheat-stem Saw-fly originally subsisted the most importlAt in the West areT r/^L^^ ^'""' Agropyron, of which gener lly known as Awned WrgrU Ld WesK r ' T"^ ^^ ''"^'*"' ""''^ The first of these is a true buSJSsthplJIlr ?",-^ "?'^' respectively, grass, bv underground root-stocks t'v^ ^Jf'"'*'''' ''^^ *^^ ^«™™on couch of so^e importance whHe at S^^ '« «»«ther host plant abundantly. P'uuutea nies, the tirst-named genus quite Among cultivated grasses. Western Rvp irmaQ cj » ^ extensively in the Prairie Provinces for hav ^^^nm r^' "T'T^ "T «''°^" ..VIV:: 23 Trco:S,::Tll„t wtHirr i„''Tht"''%°: l'- '^^^^'^'"•^- -- ^-nC at .mportcdweedJsahoHtplanTofVuehirapo^^^^^^^^^^^ ^^™/'^^«« -P-., an METHODS OF CONTROL. i^ ^^p^i^:::^!:^ ^n to a ,.,,, of „ot should be thoroughly packed Afterwards- thU ma!- r ' ^fT""^ -V'""'-- The soil snows an« fh? ^^^^^^^i^^^^ ££ t^-r T ^* ^^^- t'^e aj^s=hoS^s^tei3^ as at^trSf S iMUSa^^^^^^^^^^^^^ - -elS value P^^tion of the stem, located beC "^^'ZuntZ^i: &l^^^^^^^^^