a elacansberates os i Pew ative bo =e elton eT NaAvosalla piper paneer ety a tented irene o™ Me ecciaiahalel F Rode inet gone! eats at Np toting tt hairo tt porn ra- ean iteih taal pty ah leer eres rt Tactile ernie rf 46a he at otnd s bamada! ¥e . 2) ‘ nella 7 a ee irate cease +t ta hele "ent . ¥ ¥ > Historic, archived document Do not assume content reflects current scientific knowledge, policies, or practices. UNITED STATES DEPARTMENT OF AGRICULTURE LIBRARY vgW a Werk el le ig Ue NeSe g tVe cd Lv-idl / 5) 191919012 jyvwvVvzA ivizg=-1913 USDA, National Agricultural Library NAL Bidg 40201 Baltimore Blvd | Beltsville, MD 20705-2351 at ar yy ht ae CoS) DEPARTMENT OF AGRICULTURE, BUREAU OF ENTOMOLOGY—BULLETIN No, 115, L. O. HOWARD, Entomologist and Chief of Bureau. PAPERS ON DECIDUOUS FRUIT INSECTS AND INSECTICIDES. I. LIFE-HISTORY STUDIES ON THE CODLING MOTH IN MICHIGAN. By A. G. HAMMAR, Entomological Assistant, Deciduous Fruit Insect Investigations. Il.* THE ONE-SPRAY METHOD IN THE CONTROL OF THE CODLING MOTH AND THE PLUM CURCULIO. (SECOND REPORT.) By, A. L. QUAINTANCEH, In Charge of Deciduous Fruit Insect Investigations, AND E. W. SCOTT, Hntomological Assistant. [ILS LIFESHISTORY OF THE CODLING MOTH IN THE SANTA CLARA VALLEY OF CALIFORNIA. By P. R. JONES anp W. M. DAVIDSON, Entomological Assistants, Deciduous Fruit Insect Investigations. GRICUL WASHINGTON: GOVERNMENT PRINTING OFFIOE. 1915. wea pats Ruse wae Ae N ; , hi hits Fee COR Ae rey ‘ i< 5. ; ny i i fs if a Pay SP Rie MAR Ate pn Coa heh aosnet he 1D) 2 Ree a BUREAU OF ENTOMOLOGY. L. O. Howarp, Entomologist and Chief of Bureau. C. L. Martart, Entomologist and Acting Chief in Absence of Chief. R. 8. Currron, Chief Clerk and Executive Assistant. F. H. CuarrtEnDEN, in charge of truck crop and stored product insect investigations. A. D. Hoprxtns, in charge of forest insect investigations. W. D. Hunter, in charge of southern field crop insect investigations. F. M. WEBSTER, in charge of cereal and forage insect investigations. A. L. QUAINTANCE, in charge of deciduous fruit insect investigations. EK. F. Purities, in charge of bee culture. A. F. Buresss, in charge of gipsy moth and brown-tail moth investigations. Rota P. Currie, in charge of editorial work. MaBeEL CoLcorn, in charge of library. Decipuous Fruit INsEect INVESTIGATIONS. A. L. QUAINTANCE, in charge. Frep E. Brooks, Joun B. Git, R. L. Nouearst, A. C. BAKER, R. A. CUSHMAN, J. F. Strauss, W. F. Turner, J. H. Parnes, E. H. Srecier, W. B. Woon, F. L. Smanton, E. B. BLAKESLEE, H. B. ScamMELt, entomological assistants. EK. J. Newcomer, W. M. Davipson, A. J. AckERMAN, R. J. Fiskr, Dwicut IsEty, KE. W. Geyer, A. I. Fasis, B. R. Leacu, H. G. INcrerson, H. K. PLANK, scien- tific assistants. BE. W. Scott, W.S. Assort, © E. Dubey, JR., employed in enforcement of insecticide act of 1910. v SMES i: bs Ja ee My Banh AS Rest % af sae vy ves. SSN ete x CONTENTS. Lire-HistorY STUDIES ON THE CODLING MoTtTH IN MicuiGAN. A.G. Hammar... feminine cng ee kw eat el ee Fe Rc rcyaa (ioe ie eyes ee Mae Ry bominlomy@ EACORMGHUISe Cs ec oye alee eau Re) eugene aaa aa eioes Meccan a age Sewsomal-nistory SuIGIes Of G092 22 oo. als Gta see we es be ae Time of emergence of moths of spring brood...-.-..-....--.--------- Time of emergence of moths of the first brood.....-......-..---.--.-- -Band-record experiments in 1909. -.._..........-...-.! se Ly epi ite: NessOnal-MistOmT SuUCLesrOml ONO 0 oe ner ee Soa NVAIING CREM Oa ler veer ae sere ree Nes Seth es SE ee wie er eres be eee a A PEM ss ROOMOL UP s sees eg ns Hess hoe Cees ane eek tesa SUMMA rOOdTOL MOthS ASS Mee ae et oe OLE eae sin evtlEsipCOMeratione: Sa S8 rl R cy as ee iy De oe ee Renee ibhetsecond i enerawoness 8% Seo ee bg ot a A em anions ees BandlgrecoLds) let ONG sir meee. im ei Spe VN Rede ee eae pet Summary of seasonal-history studies of 1910............-.---..------ RecanOualMIStOryASoUGies Oli ss05 et Soe fk See Se et ae NOMUECe@isrearimpeMlatenial te 2 Soe ee ee ee re Wruntrereenledelagyes a0 ttre. 2 fl MO Te ai 8s es ak ee a ee REEDS NEO OMGOE UL pce hoe fe ee a ay Hore a yn eee Ai aR oe SPEEA CBO TOOCuOr MOMS yee 5 esses ea Ne) Oe 0 ee ee ee SW OMpI nS teCCOme nA RYO Ma; SAY \ 1 min eeiiy sags cot oe Ue Ns een ae pRiorPeeOnMare Mena tlOM ten era keh is 0 i ue Mh a Pree CORO sale LONE e mp s Meee tN Maal a oe Eke Ge ie ae Summary of seasonal-history studies of 1911........-....--..--..---- Weamenrnreeords ior 19091910 “and 1911s 2.282622 ee Comparative life-history studies for the seasons of 1909, 1910, and 1911_.-- i TL DGT CUD ETD TUSIS ge A a oe aeRO eT Ge Ua oA! T? S90 Fi ES OUULS J CANSLSY HE at Be tp as aa Sag OMI iy seve angen xd Earth] SUBECMITISC CUS a at Li es Ree oe halts Ye BBN Na te PMc rer ch eaten OTN Spa) el Se ak NO arg) eae es DV Se ee Claes age Wade Chiame OTIS ODSErVALIONS <2 sy: woe ce Sh i Number of larval instars and molts of the codling moth..............- Cannibalism among larve of the codling moth...................--.- Codling moth larvee remaining two seasons in the larval stage. .....-- Codling moth larve feeding on apple foliage.....................---- SUDEDEIC EST eo Ci ee a eh en IL SS NR meee OG A Pa : THE ONE-SprAY METHOD IN THE CONTROL OF THE CopLING Mo7TH AND THE Pium Curcu.io (SECOND REPORT). A. L. Quaintance and E. W. Scott.. LEDER GSO as we Acar 1 OE AR a ae ae ee PO rm ee > eR BER CRENVER ES VeIRoRR Tay he ee SLU Cetin Lay eae Sed oes plete neltinmoemyo thee terete: Ser uN Ok NSA basse Ole Ba eed Ee “LOESSS SOUCY ETO KGL CUT TCO) anal ee ae I LL, ON 3 a ee Page. WAN Pr ww WD HH 87 \ VIII DECIDUOUS FRUIT INSECTS AND INSECTICIDES. THE ONE-SprAyY METHOD IN THE CONTROL OF THE CopLING MOTH AND THE Pium CuRCULIO (SECOND REPORT)—Continued. Page. Experiments in Michigan 2.) (fo 2.220 ee case oe Si ec ee a 92 Whe coding ima thas: S52 2 A et a ae 94 Experiments in Delawares soca o os SES Or ie tee As ae ee 98 ‘Whetcoadhimemiothe ie. as iy eles AS aT a Aree ene oe 100 The plum ieurewlto:\2% asses Te Nee Re eae eae ee 102 Experiments i: Kansas! 4.025 aes ae el eed ee 102 Phe: codline moths 2 4b is Se tan RNA ee a 105 Summimiary: = 8 + + + == 7 SBS==e f = : 6 =: S = oy £ = :: = i i in = : —— = == = : ——— === = 3 25 22S Sass: = —— : : ——_— 3 2 : ———_—— = = : i ‘ = 4 = =o = = SS 27309 / 2345 678 FN (2 13 14 15 16 /7 18 19 20 2{ 22 23 24 25 26 AF 28 279-303/ 1 23 4 SE 78 9 104 1219 Tuly. August September Fic. 2.—Emergence curve of first-brood moths in 1909, at Douglas, Mich. (Original.) great irregularity of the curve in figure 2 is largely due to the fact that the banded trees from which the rearing material was obtained were only examined once a week. However, certain of the irregu- larities of the curve are due to climatic influences. TaBLE IT.—Emergence of moths of the first brood or summer brood at Douglas, Mich., 1908. [Records by W. Postiff.] 10 Aug. 5 Aug. 12 Total, 194 moths. — 00 orb Septs Soin ae ri Sept. 13 1 THE CODLING MOTH IN MICHIGAN, BAND-RECORD EXPERIMENTS IN 1909. In the band-record experiments of 1909, 30 apple trees were used, of which 15 trees were located in the yard of the laboratory and 16 trees in two near-by orchards. Fall and winter apples, such as Rhode Island Greening, Baldwin, Golden Russet, Northern Spy, Wealthy, etc., were used. With these late varieties of apple a thorough test was made of the relative abundance of first and second brood larve. The results of these experiments are recorded in Tables III and IV and by curves in figure 3. 2/0 : — == : = = 2 — SS == + = $ + : = : = — : Oe = : == +— i = = = == + = — iE 190 t 7 ; —— ——- = =a 780 = == : : —— 170 + t : : St = 25 16 — — : : i = : /$0 = : = oe: = = = = —— /30 = : = = == =: S 25 ee = : : = = 720 a = : a ZS : == 2 + i : ; f 110 + + —- t = 700 = — =f : = 90 S : : == SSaaze =SSS>=25 = = = === aS —— i ——+ == —— t =I + t + a : 2 == = : os j= SS SS 7 == == Se : : = = + —— = + = === = = =: 40 = —— 7 t t + : == + Z = t Jo f= = SS —— === : E = : ; —— aS == SS SS == oe SS = —— === 0 —— : == = === — —— : = = ——t t r == ; = 2 [LD TREY EP 7 (SEE IED 6 13 20 27 4 “a 18 ES / 8 1S uly August Seplember Ocirober November Fig. 3.—Curves showing maturity of larvee of first and second broods; band-record curve, of 1909, at Douglas, Mich. (Original.) TaBLE III.—Sand-record experiments in 1909 at Douglas, Mich., by W. Postiff; com- pleted in 1910 by A. G. Hammar. Number | Number | Number | Number | Number maiared No. of | Date ofcol-| of larvee | of moths | of para- | of moths | of para- aaa record.| lecting. and |emerged,| sites, |emerged,| sites, ao killed pup. | 1909. 1909. 1910. Os 1 July 12 6 Gi Seater os eter eee |e A Pens dO eta 2 July 19 62 49 LS ener oS eae ie 9 3 July 26 66 49 (Sih | Sencar || 8 eee 11 4 Aug. 2 87 41 5 a 2 32 5 Aug. 9 81 30 2 3 1 35 6 Aug. 16 80 AL leer were 36 + 23 7 Aug. 23 85 IL eras ee 61 8 15 8 Aug. 30 138 th SR es el 110 4 23 9 Sept. 6 O2tg Esse cc eeas omnes 47 1 14 10 Sept. 13 1 ial See Gon | eee eae 88 1 35 11 Sept. 20 (Aoi zs Pree ays | hee aoe aes 119 15 40 12 Sept. 27 iTS} reeves Sea each ee aes 137 26 50 13 Oct 34 EEN ese teeeiae| |: See ee 92 12 20 14 Oct Ll Qa el ee Rater Alec se 55 3 36 15 CYS) TRS ee let rele oes Crem er | ees ee | Te | 16 OGTR DS en aS is re HE San Sl ng a ee oe | eee: 17 Nov. 1 Gyles cee ees | yeaa ee 36 2 13 18 Nov. 8 PA Al sr see eaeel Ree eee 15 if 4 19 Noy. 15 Sal line Sen esoee | eS aera Sy Al ameeeceret. 3 ‘Totala=-= 1,475 194 17 821 80 363 6 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaBLE 1V.—Summary of Table IIT; band-record experiments at Douglas, Mich., 1909. Observations. Total. | ae Observations. Total. Eee Larve and pupe collected from | Injured and winter-killed larvee. -. 363 24.6 bands 2 225 0 tree eee Soe 1,475 | 100.0 || Larve of the first brood. .........- 636 43.1 Moths emerging:: Transforming larvee of the first AQ 09 tis, 5 Us Ge aes ie Pies coe 194 13.2 broods. 3 Ve Ce aes 302 eee 194 33.2 LODO See Baie eh ees eet 821 55.7 || Wintering larve of the first POOQZ1G UO ere ae ae rere cee crsters 1,015 68.8 DrOOdZe ee ee Ge ks S135 as ee Ee 425 66.8 Parasitized lanvicesenes eae sae eee 97 6.6 || Larvee of the second brood........ 839 56.9 In numbers the second brood of larve surpassed the first quite materially. From October 18 to 25 no larve were obtained, due to prevailing cold weather. However, during the exceptionally warm November quite a number were collected which under average sea- sons would have remained undeveloped. Of the first-brood larve 43 per cent transformed the same season, while 57 per cent wintered together with those of the second brood. Of the total number of larvee, 6.58 per cent proved to be parasitized by a hymenopterous fly (Ascogaster carpocapsx Vier.). The proportion winter-killed and injured by other causes was 24.6 per cent. SEASONAL-HISTORY STUDIES OF 1910. The rearing material in the spring of 1910 consisted of an abun- dance of wintering larvae, which had been collected from- banded trees during the previous season. During the winter and throughout the progress of the rearing experiments the insects were kept in cages in an outdoor shelter (see Plate II), and were thus exposed to the normal temperature conditions. WINTERING LARVE. The wintering larve invariably consist of individuals of the two broods, as only a portion of the first brood transforms the same season to form the second generation of moths, while the other portion win- ters like all of the second-brood larve. In the orchards a great number of the wintering larve find protec- tion for their cocoons under the rough bark of the trees and in cracks and crevices in older trees, and many are frequently found imbedded in decayed wood. It is mainly in the latter places that the codling moth larvee find an escape from woodpeckers and other birds which make persistent searches for the larve during the winter. The cocoon of the wintering larva.—The winter cocoon of the larva is proportionately small and completely sealed, and consists of heavy walls for winter protection. In appearance these cocoons vary con- siderably, depending largely upon the place selected by the larvee. Under loose bark, where the larve are not limited in space, the co- coons are more or less oval, as shown in Plate I, figure 3. A slight PLATE II . S. Dept. of Agriculture. gy, U Bureau of Entomolo Part |, Bul. 115 ( IVNIDINO) HOIIA| Sv19N0d LV LL6GL GNV OL6L NI HLOW DNITNGOD SHL ONINVSY NI GASf YALISHS YOOGLNO ——— —_——— SO —- — ~. ——_—— = - —-— —~ ——— me 5 ate, THE CODLING MOTH IN MICHIGAN. 7 depression is made in the bark, the walls along the exposed sides are constructed from fragments of bark held in place by silken threads, and the inside is finally lined with a thin layer of silk. Within the small space of the cocoon the larva will be found in a doubled-up posi- tion. In the spring, previous to pupation, the winter cocoon is partly remodeled by the larva (see Pl. I, fig. 4), and provision is made for the issuing moth by the construction of an exit tube (see Pl. I, fig. 5). This is partly made from fragments of the original wall of the cocoon and partly by the addition of new fragments of bark. Depending upon the location of the cocoon, the exit tube varies in Jength from one-fourth of an inch to over linch. The purpose of the tube must be to provide a safe exit at the critical period of the emer- gence of the moth. Within the cocoon over the opening to the exit is placed a thin sheath of silk which is ruptured by the pupa at the time it wriggles out (see PI. I, fig. 6) to give issuance to the moth. The transforming larve of the first brood also make their cocoons with an exit tube. The cocoons of these larve, however, are only used for a short time and are hence of a more primitive construction. Variation in size of wintering larve.—tIn size the wintering larvee vary considerably- (see Pl. I, fig. 7). There exists naturally a certain amount of individual variation, but in addition there are climatic factors which tend to increase this variation. The wintering larvee of the first brood are for the most part fully developed. There seems to be a tendency for undersized larve to transform the same season, as if less fit to pass the winter. Of the second-brood larve there are always a number that fail to attain full growth in the fall, and others totally fail to enter hibernation before frost sets in. Larve para- sitized by Ascogaster carpocapse are seldom more than half grown and lack the pink color of the healthy larva. Judging from the uniformity of head measurements, the wintering larve, though variable in size, are probably to a great extent of the last or sixth instar. (See p. 78.) Wionter-killed larve.—tIn earlier studies of the codling moth the writer has noted that killing due to cold occurred more or less fre- quently among wintering larve. During the spring of 1910 and 1911 more definite data were obtained showing a rather high percentage of winter killing. Thus, of the total number of larve from the band records of 1909 (Tables III and IV), 27.6 per cent failed to develop. A mortality of about 4 per cent may be ascribed to injury from the handling of the insects, while the rest, 20 per cent, succumbed mainly to injury from cold. Under normal conditions in orchards the per- centage of larve killed from cold is undoubtedly lower than the above figures because a proportionately large number is always destroyed during the winter by woodpeckers and nuthatches and in the spring, summer, and fall by predaceous insects and parasites. 8 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. It is quite noticeable that larve in exposed places or in poorly con- structed cocoons are more frequently killed by cold than are those well protected. As generally recommended under the control of the codlng moth, it will be well worth while in orchards to eliminate the favorable hiding places of the larve, particularly the wintering brood. Such places are old stumps, decaying trunks, and branches of ill-kept trees, where cold weather little affects the larve or where their enemies can not readily reach them. SPRING BROOD OF PUP. Methods of recording pupation.—On account of the fact that pupa- tion takes place within the cocoon it is often difficult to record this transformation without disturbing the insect by exposing the cocoon. Fig. 4.—Device used in obtaining pupal records of the codling moth. ( Original.) Different workers have often used small glass vials, within which the larve have been compelled to make their cocoons and transform. This method is very unsatisfactory when we consider the habit of the larve under normal conditions. The larva, in the construction of the cocoon, either in cracks of wood or under the bark of trees, gnaws off a certain quantity of particles of wood or bark and from these the cocoon is largely made. Furthermore, under normal protection the larva suffers less from outside fluctuating temperatures than might be expected in a tube of glass. Formerly the writer used soft strips of wood with narrow inter- spaces of one-eighth of an inch which the larve could enter and there spin their cocoons. To observe the larve and pupz within it was necessary to pull the strips apart, thus exposing the cocoon. Later it was found that when a thin film of transparent celluloid was placed in the interspace so as to cover the wood on one side the larve pro- duced their cocoons in a normal manner and at the same time left the e THE CODLING MOTH IN MICHIGAN. 4 side against the celluloid more or less uncovered, so that the insects could be observed within their cocoons without disturbing the latter. Some larve, however, particularly when exposed to too much light, would line with silk the side of the cocoon against the film. The diffi- culty in such cases was overcome by cutting in the film over the cocoon a small lobe or flap which could be gently lifted for the neces- sary exposure. This device is illustrated in figure 4. The upper _ figure shows the lower side with numbers corresponding to the posi- tion of the cocoons within. In the central figure several larve and cocoons are seen protected by the celluloid film. ‘The two strips of wood are held together by a pair of common paper clips which have been bent and adjusted to the shape desired. & oe 2) oO = s) a v £S = 2) JE, 13 16 19 2225 28 3} 4 7 10 13 16 19 22 252831 3 6 4 12 15 16 21 24 i April May June So, an, Oo, HO, Oo, a, OF vn, i a, S, an, °°, Ji@yuauye 4 — aunpeueduia, Ajrep ebeuaeny’| Fic.5.— Diagram showing time of spring pupation of the codling moth in 1910, at Douglas, Mich. (Original.) Time of pupation.—Owing to the very warm weather during the spring, pupation had commenced by April 15 (see fig. 5). However, with a change to cold weather that followed, pupation was inter- rupted until the latter part of May, and most of the larve pupated during the brief period from May 19 to May 31. The last pupa of this brood appeared on June 23. (See Table V.) TABLE V.—Pupation period for the codling moth in the spring of 1910, at Douglas, Mich. | No. of Date of No. of | Date of No. of | Date of No. of | Date of larve.| pupation. || larve. | pupation. || larve. | pupation. || larve. | pupation. 2 Apr. 15 5 May 25 2 June 4 4 June 14 1 Apr. 30 3 May 26 2 June 5 3 June 15 1 May 6 2 May 27 1 June 6 2 June 17 4 May 19 9 May 28 2 June 7 2 June 19 1 May 20 8 May 29 2 June 8 1 June 22 21 May 21 + May 31 1 June 2 June 23 14 May 22 1 June 1 4 June 10 13 May 23 2 June 2 3 June 12 May - 24 2 June 3 1 June 13 10 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. Length of spring pupal stage-—The results of observations on the time of pupation and emergence of 106 individual insects are given in Table VI. Those pupating in April remained in this stage for the exceptionally long period of 59 days. The majority, pupating during the latter half of May, remained in the pupal stage about 30 days, while later larve, pupating about June 15, remained in this stage only Onto 15 days. (See Table VI.) The average for the entire spring brood of pup was 26.02 days. TABLE VI.—Length of pupal stage of the spring brood, Douglas, Mich., 1910. Naot Date of NGS Date of obser- Days. || obser- Days. VERO: Pupation. | Emergence. VENIO Pupation. |Emergence. 1 Apr. 15 June 13 59 54 May 25 June 22 28 2 Apr. 30 June 15 46 55 SsCWLaces PAGO Saat 28 3 May 6 June 17 42 DO sea COl en os eed Ouaees 28, « 4 May 19 June 18 30 Sian Seadonee Udon 234° 5 do | une 9 31 58 =O a5 June 23 29 =F 6 CO eee ee GORE 31 59 May 26 June 22 27 7 Padoee es eoune E20 32 60 ssOOsscce SGO-52 27 8 May 20 doeaer 31 Gee kCOssecee = June 23 28 9 May 21 June 18 28 62 May 27 June 22 26 10 “GOL eee June 19 29 63 Ped Ones Medoer 26 WE. Wee sOWscccsse June 20 30 64 May 28 |_..do... 25 12 SGdOer ens BOOMs ae 3 65 SEOs 55c SIdOs 25 13 EadOne BGO eee 30 66 520Wsse% Eadore: 25 14 BACLOne = a0 Osscs6e 30 67 donee June 23 26 15 done ROOMS sae 30 68 50sec SO eee 26 16 = OS ae eae tees 30 69 SOO se5 eRdOes +5 26 17 356s5- ma OMe 30 70 5 a0Wsec0 COr uae 26 18 a LOE June 21 3L 71 Sedos== Eedolze= 26 19 Glo... BE OKOSEe Ss 31 72 May 29 June 19 21 20 50M s5c ~c6Mso56 31 tS S60 sec June 23 25 21 ..do ECOne 31 74 he donee KGOssse ee 25 22 PLMOSSSe ae _.do.. 31 75 eos SOOnsecose 25 23 36Osses Endous 31 76 =0Oss- “6s. 25 EY, Noe OlOs55- exdous 31 77 May 31 Saou 7} 25 OO scee SCO n aes se 31 78 .do... cOOs5- 23 26 sone June 22 32 79 June 1 5 5OMaae 22 27 Be GOssee June 24 34 80 June 2 =d0e== 21 28 May 22 June 21 30 81 do.......| June 24 22 29 Ea dOnee LO OMeaa ss 30 82 June 3 June 23 20 30 do PEO s55qeu 30 83 sa0Oceccoa|| dina, OY 21 31 eAdOn= SOO ss55 se 30 84 June 4 June 23 19 32 aedoue Nd Os-eeee 30 85 June 5 doze 18 33 = 66s. = Os eae 30 86 Ed OMe eleanor 18 34 (Lome aC Ose ae 30 87 June 6 EOOnes eae 17 35 a dow Osea 30 88 June 7 June 24 17 36 be Oue LLC Ondakse 30 89 HAO sealed eae 17 37 = EOk0)5 UNG Owais 30 90 June 8 dol: 16 38 S.dozs June 22 31 91 June 9 June 25 16 39 ead ous June 23 32 92 June. 10 June 20 10 40 does BuO OBssaese 32 93 su Gna sae June 24 14 41 May 23 June 21 29 94 580 Or sc June 25 15 42 dos: OWS Se 29 95 = 26M ss¢ June 26 16 43 esdoz 1doee== 29 96 June 12 On 14 44 YOU). June 22 30 97 doses June 27 15 45 ..do BACK bs se 30 98 .do... ~6Mescnses 15 46 Bados ES doe 30 99 June 13 XO (Qe ety a 14 47 Sno Sedons! 30 100 June 14 June 28 14 48 ..do EaCdOnee 30 101 6ls5- June 29 15 49 08 SaCkos5,. 30 102 June 15 June 28 13 50 LOM see te |e dos 30 103 donee June 29 14 51 May 24 Goze 29 104 June 17 Jiulys 2 15 52 seCko.- AO ab see 29 105 June 19 June 29 10 Dom PE GLOeee June 28 35 106 June 23 July 8 15 ASVOTA CO Se Ss he ek TAIT ot ea a ee 26.2 Mia xcirmnne is nS Rh SND Ct agk A ES C e 59 Minimum < Bo) ee pA RS Ne en 10 THE CODLING MOTH IN MICHIGAN, id TaBLE VII.—Length of pupal stage of the spring brood, Douglas, Mich., 1910; sum- mary of Table VI. Num- Num- Num- Num- ber of | Pupal || ber of | Pupal || ber of | Pupal |} ber of | Pupal obser- | period. |) obser- | period. || obser- | period. || obser- | period. vations. vations. vations. ||vations. Days. Days. Days. | Days. 2 10 1 19 2 27 1 35 1 13 1 20 6 28 1 42 5 14) 3) | 21 a 29 ] 46 6 15 || 2ne| 22 25 30 1 59 3 16 || 2 23 12 31 3 17 7 25 4 32 2 18 7 26 1 34 ee ] SPRING BROOD OF MOTHS. Time of emergence (fig. 6, p. 12).—Notwithstanding the changeable weather conditions during the spring of 1910 the codling moths emerged with striking uniformity. The earliest moth in the rearing cages « »peared June 13; the great majority of moths emerged between June .8 and June 30; isolated moths continued to appear up to the close of July, when the first moths of the summer brood commenced to issue. The maximum emergence took place June 22. The emer- gence for the spring brood is given in Table VIII. TaBLE VIII.—Time of emergence of the spring brood of moths during 1910, at Douglas, Mich. Num- Num- Num- Num- Wap Gi seals of WS? Gi Date of Hewon Date of ina OG Date of aaGNTne. ergence. |/ noths, | emergence: || moths. | emergence. || moths. | emergence. 5 June 13 59 -| June 25 7 Uolky Oi Wiscsodose July 19 5 June 14 56 June 26 6 Volhy 5 ileseossoa! July 20 1 June 15 81 June 27 6 July 9 2 July 21 4 June 16 36 June 28 0 divily, NO NWescécese July 22 17 June 17 45 June 29 5 July 11 1 July 23 40 June 18 53 June 30 8 Yiollky IW: WSececosc July 24 52 June 19 33 dw We MWesceesce Diutlivare| Siamese July 25 82 June 20 34 July 2 i) AGIA WE Weteeseus July 26 162 June 21 19 dilly B Weeeobeae July 15 || 2 July 27 232 June 22 9 oily 4b Me ccbooos July 16 199 June 23 10 July 5 6 July 17 128 June 24 10 duly ~@ Mesosscat | July 18 Variation in size of moths of the spring brood.—The moths of the spring brood vary considerably in size and to a greater extent than do those of the summer brood. (See Pl. I, fig. 1.) This might be expected on considering the difference in size of the wintering larvee from which the moths result. There have often appeared dwarfed specimens of moths from the band-record material which at first sight could hardly be recognized to be of the codling-moth species. That there should exist a correspond- ing difference in the vitality of individual moths is only natural and 1s fully reflected in many of the results of the rearing experiments. In view of the great variability in behavior of the insect it has been necessary to conduct many of the experiments on a large scale in order to establish reliable averages. 35215°—Bull. 115, pt 1—_12——2 12 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. Time of oviposition.—The time of oviposition in orchards may be determined with fair precision from the combined data on the habits of the moths in captivity, the rearing experiments, and the field observations. In rearing these insects eggs may be readily obtained by confining a number of moths together in cages. It is not possible to determine the number of eggs thus produced, but the time and period of egg deposition can be ascertained. >, &, Beuony 7p) ES _— oO vas = re) co 5D) YO & >) VE ployueuye4-eunyeueduies Aprep 2@ 00S OOS82 S000 SSE SS8 SOS Ree Es SERS SeESs Sane" BEE 28." .0ab \=e CS Prete Sy 18 20 22 24 26 2830 2 4 6 & 10 12 14 16 18 20 22 24 26 28 June July Fig. 6.—Emergence curve of spring brood of moths in 1910, at Douglas, Mich. (Original.) TaBLE 1X.—Egq deposition of the spring brood of moths in cages in 1910, at Douglas, Mich. Date of— Number of days— From No. of caeel Before date of cage. | moths First. Last. ae Of egg | emer- *|EKmergence.| oviposi- OVIPOSIS Cee deposi-| gence tion. tion. Sain tion. | to last oviposi- tion. 1 5 June 14 June 19 June 21 5 3 7 2 3 June 16 June 20s pea doe 4 2 5 3 15 June 17 June 19 June 25 2 7 8 4 36 June 18 June 20 June 26 2 7 8 5 57 June wo eee doses June 27 1 8 8 6 87 June 20 June 23 June 29 3 7 9 a 262 JUNC 22 ieee GOzseee July 4 1 12 12 8 25 June 24 June 29 July 2 5 4 8 9 29 Meine) A esse CO accce July 10 4 12 15 10 27 June 27 July 2 Vwllyy 7 5 6 10 11 16 June 28 July 1 July 3 3 3 5 12 24 June 29 Aju 74 July 10 3 9 11 13 36 June 30 July 3 July 9 3 7 9 « 14 25 July 2 Apoyo decace doseere 7 il 7 15 8 July 6 Jul July 11 2 4 5 16 5 July 9 Aoi, al eed O@-so5- 2 1 2 17 5 July 11 July 14 July 14 3 1 3 Average number of days..... Deas ees Meee nee 3. 24 ys} 7.76 Maximiim num benoldaySeemecereeeee eects se tees 7 12 15 MinimimeniimibenondaySeessee seer eeeeeeeeee ere. 1 1 2 THE CODLING MOTH IN MICHIGAN. 13 In Table IX are given the results from 17 separate ‘‘stock-jar’”’ experiments, so called because of the nature of these experiments. Medium-sized glass jars of about 1 gallon capacity were found to be well suited for the purpose. To provide for a certain amount of moisture a layer of damp sand was put in each jar; food was fur- nished. the moths in the form of diluted sugar and honey solution placed on a small piece of sponge. In each cage a certain number of moths, of known date of emergence, was confined, and throughout the course of the experiments a daily record was kept of egg deposi- tion and the length of life of the moths. The eggs were laid indis- ‘criminately all over the cage, on the sand, on the sides of the glass, on apple foliage and fruit, and on the cloth cover of the jars. When too many moths were confined together eggs were even placed on the wings and backs of some of the moths. For the purpose of recording the egg stage it was found desirable to have the moths Oviposit on pear leaves in place of fruit because the leaves darken upon withering, so that the light-colored semitransparent eggs may be better observed. Each day fresh foliage was placed in the cages, which insured eggs of a given date of deposition. On an average the moths commenced to gviposit three days after the date of emergence and most of the eggs were laid within a week of emergence. In a few extreme cases eggs were laid the second day after emergence. In one instance the last eggs were laid 15 days after the date of emergence. (See Table IX.) Several moths in the stock jars survived from 19 to 25 days. Length of life of moths —A summary of observations on the life of 529 moths is given in Tables X and XI. The average length of life was 9.44 days, the maximum 25 days, and the minimum 2 days. These moths were from the stock-jar experiments previously de- scribed. TABLE X.—Summary of observations on the length of life of 529 moths of the spring brood in confinement, Douglas, Mich., 1910. Number |} Number || Number | Number || Number | Number || Number | Number of moths. | of days. || of moths. | of days. ||ofmoths.| of days. || ofmoths.| of days. 8 2 118 8 60 13 9 18 1 3 16 9 14 14 || 6 19 8 5 AT 10 7 15 || 1 20 74 6 28 11 9 16 | 1 25 70 7 44 12 8 17 Days alive IAWFETR EC! Beak oo has als. os ahs 9.44 INET ETN ee eee ee 25 Mainimiuwmt. hone. oem ese se 2 14 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. THE FIRST GENERATION. FIRST BROOD OF EGGS. Length of wncubation.—The eggs of the first brood on an average hatched within 6 or 7 days. Under low temperature the maximum length of time was 10 days. The shortest period of incubation was 4 days. (See Table XII.) TaBLE XII.—Jncubation period of eggs of the first brood laid in rearing cages, Douglas, Mich., 1910. | Date of— | Duration of— | No. of Date of | obser- | egg depo- — Appear- | Appear- vation.| sition. dricelof red | ane of | Hatching. | Red | Black | Incu- ring. black spot. ring. | Spot. | bation. | Days. | Days. | Days 1 JUNE 20's Pe See A ae ae ee eee TitT C29 Fas | eee ee ee| 9 Pa Nee OKO ae (eee A pl Rn ne 50, ae Se diowney Bir Ae a eS hen | 10 3 ATO OPN [ike So es eee June 28 Aus AE) 2S - 6 7 Ase Olea | ee ere Ones June FSO Ns eee Gua 8 5 JUIMe) 3249s | Gael e eee Diualyy fag | eee 7 6 SUMS D5 ees eee See | ere Jaliy 32S '| coos 2 ree i a June? 2677 (Pets tao eels eee DO ss Se52 3 ER Seal eee 6 8 Ati ea7(ie eeamse see oc Sameer ah ha han Nee eet Se ens 6 9 JUNC AZS re EAS ease ees Muriby; pee i] (Se eee se ee eee 6 1024) 2 CO S22 es |Sae eke pemeee he Diruliya Ss 0p) | ek ee | er eee 7 11 UTS 129) ere ee July 3 AEM pe teh SE ee 4 5 12 Ores. Sau Sees |e do... Sulivee ios | eee ree A 6 13 June 30 July 3 July 5 July 6 3 5 6 14 (0) SCO ees hee do.. July 7 3 5 if 15 Uh We sSCO.< July 6 dostsees 2 5 6 16 .do. cad Osr sees. es do.. July 8 2 5 7 17 July 2 July 5 July 7 do2 es 3 5 6 18 July 3 July 6 July 8 July 9 3 5 6 19 Rokisaewsce ESO Kee eal ees dove: July 10 3 5 a 20 divthy 4b ie oCOsecaee July 9 = OMS eee 2 5 6 21 dose ees? aC OS ae July 10 July 12 2 6 8 22 July 6 July 9 July 11 July 13 3 5 7 23 Gosh aoe a= GOSS eee dotseeee July 14 3 5 8 24 July 7 Cae el oes doszcues July 13 | 2 4 6 25 July 8 July 10 July 12 July 14 2 4 6 26 July 9 July 12 July 14 July 15 3 5 6 Pf Pal ie 0 Ke sea e July 13 ROWS Aas = July 16 | 4 5 7 28 July 12 July 14 July 15 doses 2 z 4 20) || - 2G On ceieesisas (Kayes ees Ie 2 On 22: July 17 2 3 5 RO eseOls ss scallese donee July 16 July 18 2 4 6 IS ELAR OG. liao oe gn tac A ane a 2:5 | wae ece Micexa Oe ee eee eee th Ps «oe ra eee 4 | 6 10 MGT IMs Se cee oe eee ee ee nae ee ee 2 | 3 4 | The so-called ‘‘red ring”’ of the egg appeared from two to three days after egg deposition, and the ‘‘black spot” from one to two days pre- vious to hatching. The eggs used in these experiments were laid in cages on pear foliage. Records on the development of the eggs were taken once daily between 9 and 10 o’clock in the morning. . FIRST BROOD OF LARVA. Time of hatching.—In the field the actual time of hatching and the relative abundance of newly hatched larve may be fairly well deter- mined from the different data on hand relative to the time of emer- gence of the moths, egg deposition, incubation of eggs, length of feeding of larvee, and the appearance of mature larve, as shown by the band records. In correlating these facts the time of hatching is estab- lished as given in the diagram of figure 11. The earliest eggs were deposited June 17, the maximum oviposition was reached at the close of June, and a few late eggs were laid up to THE CODLING MOTH IN MICHIGAN. 15 the end of July. Incubation of the earliest eggs lasted nine days; for eggs laid about June 30, six days; and for later ones laid during the middle and latter part of July, only four to five days. The larvee from the Saugatuck band records (fig. 9) reach a maximum July 31, and inasmuch as the average length of feeding for this brood of larvee was 27 days the date for the maximum hatching would be July 4. On the other hand, on the basis of oviposition and length of incubation the height of the hatching period would be July 6. Length of feeding.—Reference has already been made in the pre- vious pages to the fact that a portion of the first-brood larvee do not transform the same year, but winter and complete the life cycle the following year. The transforming and wintering larve differ in the length of feeding, and the latter are often materially larger in size. Thus on an average the transforming larve remained in the fruit 25 days against 29 days for the wintering larve. (See Tables XVI and XVII.) For the entire brood of larvee the shortest feeding period was 17 days, the longest 45 days. Time of maturity of larve.—tin the field the time of maturity of the larvee is determined from the band-record experiments (fig. 9 and Table XXVIII). Thus the period for the first-brood larve - at Douglas, Mich., extended from July 10 to September 10. After the emergence of the moths from the band-record collection it may further be possible to determine the time of maturity of transforming and wintering larve of this brood. The last transforming larva left the fruit August 8 and the first wintering larve left the fruit July 20. There is also a difference in the appearance of cocoons whereby the two sets of larvee may be recognized; the transforming larva provides the cocoon with an exit tube, while the wintering larva produces a closed cocoon. (For full description see pp. 6-7.) Percentages of transforming and wintering larve.—From Table XXXI it will be found that 201 larve of the first brood transformed the same season, while 368 wintered, or 35 per cent transformed and 64.1 per cent wintered. Somewhat similar results were obtained from the rearing experi- ments, though these can not be as reliable as the data from the band-record experiments, since the former are from a limited num- ber of observations. Out of a total of 51 larve, 21 transformed and 30 wintered, or 40 per cent transformed and 60 per cent wintered. (See Table X XII.) Larval life in the cocoon.—The length of time required for the making of the cocoon depends largely upon whether the larva is to transform the same season or to winter. A slight individual varia- tion of time naturally does exist for either set of larve. In case of wintering larve it is difficult to decide just when the cocoon is completed. The transforming larve cease to be active from two to three days before pupating. For these, then, the larval life in the cocoon can be readily determined, being considered as the period from the time of leaving the fruit to the time of pupation. 16 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. In Table XIII are given the results from observations on 117 indi- vidual insects. Further records on the same topic are found in Table XVI. The larval life in the cocoon varied from 3 to 15 days with an average of 7 days. In case of a very short period of from 3 to 5 days the larve abandoned its first cocoon and made a new one. The records, however, only show the time consumed for the making of the last cocoon. Such cocoons are very primitive in appearance and have not been completed. TaBLE XIII.—Length of the pupal stage of the first brood, Douglas, Mich., 1910. D f— D — RrOnaE ae Lar- | Pu- Nas of BeKOF Lar- | Pu- obser- vee in pal obser- ve in pal vation.| Leaving | Pupa- Emer- ee Be vation.| Leaving | Pupa- Emer- ee Bae fruit. tion. gence. 5 ; fruit. tion. gence. COPE S Days.|Days. Days. | Days. 1) July 22 | July 25] Aug. 9 3 15 60 | July 29! Aug. 4] Aug. 20 6 16 Dil 2do-.. =.) dale: 26) 5 dora 4} 14 61 | July 30 )...do....| Aug. 17 5 13 Si MECC ORSS Siieac doses |F2-doxaae 4 14 62. don se 4) saad Ones enone 5 13 4|...do.. a LOE es] eee eye t 14 Gir |. dps. Sd Ghee ip ne do.. 5 13 5 |...do ACOs Ee) PAUICS 13 4 18 64\0 2. dos. ce|a-2dose es AUee rs 5 14 G52 doee ..d0...-} Aug. 15 4 20 65) aides 54-2 det a asda. oe 5 14 Zi Neac@ce Be 6 (apy craue Ppee(o Yo yer + 20 66) | 222 doses |22sdot se 25200 5 14 8 |: 2-do- _.do... .f Aug: 20 4 25 64 |e2 do? 455 doa |e idous ae 5 14 9|...do Aug. 6] Aug. 19 15 13 68 | dogaeal= dose Aug. 19 5 15 10 |...do T21des— =~) Mus. 20 15 14 Se emer: (0 ee Aug. 21 5 17 11} July 23 | July 29 | Aug. 13 6 15 Q |. .2de....| Aug. 5, | Aue. 18 6 13 12 do Aug. 4] Aug. 17 12 13 LN CS tos Ses eAUe, Onl aendorrs a 12 13 do ---d0... 0 12 13 (2)\ 3200s - ~-d0.- Aug. 21 a 15 14| July 25 | July 30| Aug. 15 5 16 7 }..-do0..-.| Aug. 7) Aug. 18 8 11 15 doz... Awe. 1 0) 7 14 (4,22 do.) Atise (Ou rAni essa 10 12 16 doves a eAua. (3 do 9 12 LONE SOs a cae dO: =d0= 10 2 Ges Onarale Sh One do. . 9 12 TAD EN FG a Caen ays des. 10 12 18 dou =| Peadore Aug. 16 9 13 77 aeedoe Aug. 24 10 15 LOPE Gorre 4.d02 Eudaae 9 13 78 | July 31) Aug. 4] Aug. 17 a 13 20 | July 26 |...do. 72 ao- 8 13 1D) | dOna- | £5 500245 do 4 13 2 eee dOee ae | asAdOr .-do. 8 13 S04 doses 2 =. doz Aug. 18 4 14 Pepi OK ais | SOKO BEOO) 8 13 81 do.. Aug. 5 GOnce 5 13 23) sde ) <2. da .. do. 8 13 82 do....| Aug. 6] Aug. 19 6 13 ZA Nes Oars ees ae Ont aE Osc 8 13 83 dose sadoes Aug. 20 6 14 2d Oa. =e do Aug. 18 8 15 84 dar 2e2 | Awe? do 7 13 2G) se CO Srereye | PeAT Sean Aa ALT alZ 9 13 89 doses 25 don: Aug. 21 7 14 27 | July 27| Aug. 3/ Aug. 13 7 10 86 |._..do.. Aug. 91] Aug. 22 9 13 28 One Se nee do= Aug. 15 rb 12 SiS ot aaa end One dos: 9 13 29 doztee 2 -dols Mende 7 12 88 | Aug. 1| Aug. 4] Aug. 18 3 14 30 doss=s\22edoz do 7 12 89 |...do....} Aug. 5 | Aug. 19 + 14 31 GOs saa 2 Gre -do.. 7 12 90:|...do....| Aus. 6°} Aug. 18 5 12 BY Fee OO se nie BECO se Aug. 16 7 13 91) doe he Oss amAL cael 5 | - 13 Sons GOsee ae dors do... ui 13 92" | does 2/2200 l 255) Aue 20 5 14 eb EKO Os evel nigeKO ae do. . 7 13 WEY SE KCOE G aligeeO los. COLO Cees 5 14 BNE AO Msoe chancCOAe Aug. 18 € 15 CEE ekO Oe 8 al EO OL Se do. 5 14 36 |...do Pedore do 7 15 95 do....| Aug. 8 | Aug. 21 7 13 ot) |'--- doz Aug. 4] Aug. 15 8 11 96) |) S22 dour Ss Aus 9a edo. 8 12 38 do. “dos Aug. 18 8 14 97 dO. 2 2.c}2-20On52 =| Awe 322, 8 13 39 do Aug. 6] Aug. 20 10 14 98°| Aug: 4°) Aug. 125)". ¢dors = 8 10 40 | July 28 | Aug. 3} Aug. 15 6 12 99. |...do.....| Aug. 13 | Aug. 25 9 12 Ale dO nase ted Owe Aug. 16 6 13 100 ;...do..-..| Aug. 14} Aug. 26 10 12 AD ee QOe sa. COs se 0. 6 13 101 do.. Aug. 15 | Aug. 29 11 14 43 GOe eal Onan AUT Ong 6 14 102 GOR AleeeOe Aug. 30 11 15 t4 doz. sp Auge .4 |i dot 7 13 103 | Aug. 5) Aug. 13 | Aug. 24 8 11 Aaland Osco aacdOns do. a 13 104 do.. Aug. 14 | Aug. 25 9 11 46 do.. EadOse do. 7 13 105 do.. Aug. 17 | Aug. 30 12 13 AT do.. yedore Aug. 18 7 14 106 | Aug. 7] Aug. 15 | Aug. 27 8 12 48 do. dor. do... 7 14 107 | Aug. 8] Aug. 14} Aug. 25 6 il 49 do. SCORE BOOS. 7 14 108|-2-d02 5. -)| Aus. 15) | Aiwa 24 U 9 SOU ee Oe se fe dO dot: u 14 109). .. dbo: - Aug. 16 | Aug.- 30 8 14 Send ose Aug. 5 | Aug. 19 8 14 WOU esdose Aug. 17 | Sept. 1 9 15 Ban een Oa 2dG5< Cae 8 14 111 do. f2d0: OL ees 9 15 DSi seed One Aug. 9} Aug. 22 12 13 112} Aug. 9] Aug. 15 | Aug. 26 6 11 54| July 29 | Aug. 3] Aug. 16 5 13 HST dos Aug. 16 | Aug. 30 7 14 5Oy oes Ose aaa Ors 02 5) 13 114 | Aug. 10 | Aug. 15 | Aug. 29 5 14 56 do.. Aug. 4/ Aug. 17 6 13 115 | Aug. 16 | Aug. 25 | Sept. 14 9 20 57 240. <- 2)5 5200422.) Auge) 18 6 14 PEGS 2EO2 Soho. is dost 9 20 5S esd One| aed Osea aoe GO sets 6 14 117 do2s:-|) Aug. 26) 2 2sd0se 5 eeeto 19 09 -)s2 50s). agesdOnsee|te dOsaiais 6 14 ——— A VOTALC soc oo Se ues Saettate tae ete Ne Ta Teg RS oe NE al sci en GA) A326 UME URLS hr rp eS SE Se ae A se re ae ee er ce ee 15 25 u's Eu ab Bev oo amet Oo Umer Uae eager Meee UR Th Sento oe el ees tn) None oe EE eae UNE ewe 3 9 i | é i ghee. Pes hs THE CODLING MOTH IN MICHIGAN. 17 FIRST BROOD OF PUPZ OR SUMMER PUPA. Time of pupation.—The time of pupation may be determined from the records of the pupal stage and the emergence of moths of the same brood (see fig. 11) since it is to be expected that the rate of pupation approximates that of the emergence of the moths resulting from these pupe. TaBLE XIV.—Length of the pupal stage of the first brood, Douglas, Mich., 1910; sum- mary of Table X IIT. Number | | | Number | |* Pupal Larve in of obser- || of obser- | : vations. | ©°C°°D- || vations. | Period. Days. | Days 2 3 il 0) 11 4 2 10 19 5 6 11 15 6 16 12 25 7 38 13 17 8 33 14 13 0) 11 15 2 10 2 16 2 11 1 1y/ 4 12 1 18 2 15 1 19 | 4 2057; 1 25 | Length of pupal stage (Tables XIII and XIV).—The pupal stage of the first brood varied from 9 to 25 days with an average of 13.6 days. The experiments of Table XIII include observations taken during the greater part of the pupal period. TaBLE XV.—Tiume of emergence of moths of the summer brood from band-collected mate- rial of 1910. Number of moths from band Number of moths from band records at— ~ records at— Date of Date of emergence.| +; emergence. Rich Sauga- | Lake | Mota. Rice Sauga-| Lake | ota], iC tuck. | Shore. more tuck. | Shore. July 26 Dia pee | an py 2 Aug. 16 5 14 12 31 July 27 Syl | ie el Sica eae 2 -Aug. 17 3 10 12 25 July 28 | 7 2 ree ee 6 10 Aug. 18 4 3 13 20 July 29 4 1 6 11 Aug. 19 2 11 10 23 July 30 AY Sl be, est 4 8 Aug. 20 6 9 10 25 July 31 7 | es ete 9 PAC eile | ey eae 10 8 18 Aug. 1 | 0) 5 14 28 Aug. 22 8 21 28 57 Aug 2 2 16 7 25 Aug. 23 3 8 5 16 Aug. 3 7 8 10 25 WAT ORE DA sale Ree 6 9 15 Aug. 4 + 3 6 13 ANDER 74) Se ee aoe 6 4 10 Aug. 5 1 + 3 8 ANS, FA) i SE Se oe St ae eee 5 Aug. 6 11 5 8 24 Aug. 27 Dies | ea hee oss 6 8 Aug. 7 6 ae: 3 13 INGOTS GAS a lee a ibaa meer ee he 5 Aug.. 8 12 4 8 24 PATER E29 eae 1 5 6 Aug. 9 10 4 9 23 Aug. 30 1 2 2 5 Aug. 10 3 9 6 18 Aug. 31 1 eee 1 2 Aug. 11 6 1 5 12 Sept. 1 Tei ets Sea [boogeees 1 Aug. 12 6 1 7 14 See 7h ee oaoese 2 3 5 Aug. 13 6 7 5 18 Senta sea nie = 5. es | 1 1 Aug. 14 8 9 9 26 ‘Aug. 15 3 5 17 25 Total 153 | 201 | 262 | 762 18 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. FIRST BROOD OF MOTHS, OR SUMMER MOTHS. Time of emergence (fig. 7 and Table XV).—The records of emergence of the first brood of moths are from band-record material and should closely represent the actual time and rate of appearance of moths in the field. The larve used in these experiments were from three separate band records (see Table XV), and the curve of figure 7 represents the sum total of daily emergence from the combined sources. The first moth appeared July 26; a maximum of emergence occurred August 22, after which date only a few moths issued; the last moth of “ihe brood emerged September 8. From the point of view of mechanical control the time of emergence of moths of the second brood of the codling moth becomes of foremost BuaAy wos Atep 26 ri | s. 2, “Number of Moths d at oy 1) ISIS Iv lit 2le 23 25 27 24-3 20qu 6 16 August September 1) GR wy ia S Ss aul wu 25 sS © 3) 2) & = Fig. 7.—Emergence curve of summer brood of moths in 1910, at Douglas, Mich. (Original.) importance, and this is one of the phases in the life history of the insect in which the literature on the codling moth is particularly deficient. This is mainly because of the difficult task of establishing accurate data, which at present involves carefully conducted band- record experiments. It is necessary that the bands be started in proper time and that the larve be collected at regular and preferably at short intervals (three days) in order that the records on the emergence of moths may become fully reliable. Time of oviposition.—The so-called stock-jar experiments of Table XVI, including moths of the first brood, have been carried out under identically similar conditions as described on page 13 for the spring brood of moths. Egg deposition commenced from two to three days after the time of emergence of the moths, and extended on an average over a period of one week. In one instance eggs were laid 18 days after the date of emergence of the moths. THE CODLING MOTH IN MICHIGAN. 19 TaBLE XVI.—Egqg deposition of the summer brood of moths in rearing cages, Dcuglas, Mich., 1910. Date of— Number of days— No. of From : Number exper | of moths.| Emer- : : - | Before Ofe date of meni. gence of F ee pasveve first ovi- depot Sanat moths. | P oi * | position. tion. Benge position. I 10 | Aug. 11 | Aug. 14 | Aug. 19 3 6 8 2 10 |} Aug. 12} Aug. 16 |} Aug. 24 a 9 12 3 26nPANIEs 145/55 doe Sept. 1 Z 17 18 4 20 | Aug. 16 | Aug. 19 |} Aug. 25 3 7 9 5 30 | Aug. 17 |...do. 2d0e- 2 7 8 6 20 | Aug. 18 | Aug. 20 | Aug. 26 2 7 8 7 27 | Aug. 19 | Aug. 22 | Aug. 25 3 4 6 8 30 | Aug. 20 |...do. Aug. 29 2 8 9 9 10 | Aug. 21 | Aug. 25 | Aug. 28 4 4 7 10 53 } Aug. 22 |} Aug. 24] Aug. 26 2 3 4 11 J1 | Aug. 23 | Aug. 25 | Aug. 25 2 1 2 LAO Sea 5e not eae sa ds Gon OSS naa See eee 2.6 6.6 8.2 IY SoG ODN CO eee tS ks psa th ee a eee a a 4 17 18 IN Gea H GTR D IOAN S ee eae he a 2 I 2 Egg deposition by induidual moths.—Observations were taken on the ege deposition of six individual moths in captivity as given in Tables XVII, XVIII, and XIX. In most of these experiments pairs of male and female moths were used, which were removed from the stock jars before any oviposition had taken place. , TaBLE X VII.—Egq deposition by individual moths of the summer brood, Douglas, Mich., 1910. Number of individual moths. Date of 1 | 2 | 3 | 4 | 5 | 6 egg deposi- tion. Date of emergence. July 28. |} Aug. 4. | Aug. 10.| Aug. 11. | Aug. 14. | Aug. 15. Date of death of moths. Aug. 25. | Aug. 23. | Aug. 24. | Aug. 26. Aug. 14 | Aug. 12. 20 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. The moths of experiment No. 2 were found mating at 10.30 a. m., August 6, or two days previous to the first egg deposition. On an average the first eggs were laid five days after the emergence of the moths and for an average period of five days; the maximum number of eggs per female was 91; the average number of eggs per female, 35.8. These figures are lower than those from similar but later experiments in 1911. TaBLe XVIII.—£gg deposition by individual moths of the summer brood; summary of Table X VII. Number of individual months. Observations. 1 2 3 4 5 6 Totalieres per female: =. --. s\e ees tae he aoe ee eee eee 91 71 18 11 17 Zi Days beiore ese. depositions: = ste oe pa ee ee 8 4 5 6 5 2 Days durationobers depositions s esate on ee ee ee 9 3 4 5 3 6 Days aliveratteregeide position scseme == es ee eee 1 2 7 2 3 4 Days moths lived fos -2s = se. Soe sear ae er eee eee 17 8 15 12 10 11 TaBLE XIX.—Egg deposition by individual moths of the summer brood; summary of Table X VII. Observations. Average. | Maximum.|} Minimum. Hees periemal ersca- sao sn) sae See vee aie ee ae ee 35.8 91 7 BEES Per Ga yePerlern ale es se sree eae re eee ore mi op eee 7.16 36 1 Days before egg deposition per female.......-- SRE ABS ee RA be ire 5 8 Z Daysovegs depositionypertemale esse see ees ae eee 5 9 3 Dayssnochslivedtaiteresecde position sess eee ee rs eee 3.18 7 1 Days mothsiliveds=. sos55.0 =o Sass cae ewe eee oe eens oes 12.1 17 8 The moths were confined in common jelly glasses with perforated tin covers. A fresh pear leaf was inserted for egg deposition, and food was given in the form of dilute sugar and honey solution placed on a small piece of sponge. Most of the eggs were laid on the leaves, though a few were invariably also found on the glass. Judging from the records of emergence of moths and their habits as observed above, it becomes evident that the earliest eggs from this brood were laid about August 3. The height of the egg deposition period should have been September 1, and the close of the period September 15. Length of life of moths.—A record on the length of the life of the summer moths in the so-called stock jars was taken on 445 individuals (Tables XX and XXI). These moths were kept under similar con- ditions to those of the spring brood. THE CODLING MOTH IN MICHIGAN. yell TaBLE XX.—Length of life of moths of the first brood, in confinement, Douglas, Mich., 1910. | Length | | Length || Length | Length | Number. | of life. Number. of life: Number. efile: Number. eaerires | | | | | Days. Days. Days. || Days. | 5 2 70 7 39 12 || 9 17 5 15 3 49 8 27 13 4 18 | 14 4 56 9 18 14 2 19 | 34 5 27 10 5 15 2 20 41 6 23 11 4 16 1 24 Total number of moths, 445. | TaBLE X XI.—Length of life of moths of the first brood in confinement, Douglas, Mich., | 1910; summary of Table XX. bp Length Observations. Selita: | Days. | PASVIGT AS Ch asta cers ioe 8.93 Wiepahonbhans oo ee 24 Witemanbein, “45. ee dquasSane 2 The results of observations on the length of life for the two broods of moths are practically the same (compare Tables XI and XXI). LIFE CYCLE OF THE FIRST GENERATION. , In the preceding pages the separate stages of the first generation have been considered at length, and the length of time of the devel- opment has been determined by a number of experiments for each stage. The final figures from these records thus represent the average life cycle of the codling moth of the first generation. Days. Hime mo atloMeMerMod: OL COUSsee es re tee ie eos gee 6 Hewethtor feedimpioflarvec: 2 oi. 2 602222 eee ee see ene e290 hime ow lary ccum COCOONS). he We ep get orks oe yee eee Se 7 Mean theorepuipalsstace sens = ss se 2c is eee eS iene 13. 6 LOTR SS sree, Cee SI GS OAT OR otal ga Ea 51.6 To test the accuracy of the various experiments for the separate stages an additional experiment was undertaken in which a number of individual insects were carried through from the time of hatching to the emergence of the moths. 22 DECIDUOUS. FRUIT INSECTS AND INSECTICIDES. TaBLE XXII.—Length of life cycle of the first generation, as determined by rearing in 1910 at Douglas, Mich. ns - Date of— Days— a] = Feedingof—| 4 2 5 a | sessa(ceom he reales = Egg dep-| Hatch- | Leaving| Pupa- | Emer- | 3 ES Hg Ss & & < | osition. ing. | thefruit.| tion gence. || 8 | 38 | o> | Sig | sa is Z B [smo / eS | o | Bal, 8 7, Re lmE Pre esti ssa eS) pieced es 1} June 25] July 2/| July 26} July 31 | Aug. 15 7 DAR ie 5 15 51 B Alle eOWs< =aClOsceee July 4285 |e otines eee emo ies (Ot ee D26.l 2. a hao peemeebels aise B leocOsccaalleas doe July 29} Aug. 2] Aug. 18 u Di |S 4 16} 54 AS ed Ose adoOuee BD Baas 0a reese ar eter sie ars (gai eee DS's) © sO Ree ees eco DF ooeGOsee L6GOsc4 -do.. Aug. 8 | Aug. 23 7 233 eres 9 15} 59 @ een Oscee. naGlWDeesec inlhy Veul,| Awe, © is. Clo.- 7 29) Wey 9 14} 59 HNeooeOOscace =3d0: Aq B yl ey sce eel etc eee (es as Ss SON ass sla ales 8 | June 28] July 4] July 24} July 29} Aug. 13 6 7A) losocbe 5 15 | 46 0) ascCOnese- Pad Oseee dows EC \osoaeallaas do.. 6 20)al ee aes 5 15 | 46 I@ |ssoCOsce .-do. July 26] July 31] Aug. 16 6 Ck Nie 5 16} 49 WL Nooc@@sce Ose July 27 | Aug: 2] Aug. 18 6 Doi cries 6 16; 51 1B VoscGlscocelloocCWzccae eed Oe sae |e aCOre=ee Aug. 20 6 2B} \lcgcooe 6 18 | 53 18) soeC sce 560 scose dour madore Aug. 15 6 PB Nose co 6 13} 48 145 | Saad Ozesee SHO sacae Jaly2e285 Oke eee Gulees.ce BY) ates al eae Bs Ae NB lossClscsos ACOse5ee Up Si) Wega asdoullesocauouss OES DOs egal ees Semen 16} June 30 |-..do. July 23 | July 27 | Aug. 12 6 te ee 4 16 | 438 Ue NoscO@scccc Uwlhy Gl dhelhy ZS) Noeasscoccalsocscaeacc Gil Deva) rece osha | eee eer | Memes 18 |...do. ..do Uh Se Wiecemsesees||beaatonss- Wiles cee DY Ne ae amet eee id 10) oeCl@s 6 - Pedorenee AGS. alles ee ceca Saseeeien ts Galas 2GN he hau see cee 20)|eeedor LOW sscec Aug. 2] Aug. Aug. 20 6 seer ociec 4 14] 51 PA Ne coGl@ssss Ee GOseaae ~a@lOsscc6 Aug. 12 | Aug. 24 6 PAO eee Se 10 12} 55 WD | sO .-do ANI SASS oes eee eee Sees OulGaeese OA eel etree Sentecrc 237 doe ACOs HANTS FAS Ss eee rr nee aera Gileateee QOS Bol Eze emeesee 2452 ead oF —Oscces We Gul PAUSE ESep ton L 6 Sie aes 11 NGS |} 8} BS | OO soo ..do. SOUS LE Pe see os lees eee = Fels st: SiO ee ee eee XS | Yule Wi dielhy Ss ghey AS | eScccacusllecacsocade ssa ULSZE || Sees ct Se ae, | OE Naso sA0O aco Dialliycs2 Sy | eee eal os smears are fale & DALE Nigeceh tote | pears les ah 2B} aso@ Osssoe BEG ORs =o Aug. 2] Aug. 4) Aug. 18 a DOSS | on b oe 2 14 | 48 Ph) ea cOOsoses BAMOES oe Se dosease ad Oz Aug. 19 7 7 Mtoe 2 15 | 49 SORE Goue 002s PC Oseees Aug. 9| Aug. 23 7 PA a Shee U 14| 58 Bl Neale aaOlsnead BANG u Ueber WH | leanne Rel ee apenas aan lia Saree PA Peete Pee ee ie BY Wesel sadec = dOz Be eae: Gal ls ey OU lel Men ierere ial EG losesee DIA once Pen | Berea 33 |..-do. e208 ATL 20) eo aya eace sea eisee eine | rape DSi sonata Ee ie See 345 |eedoe Sedona: SASS re OR Ee ase erera| beets teen iogliseeen a QO ae meee | swam een (eee ae $35): |e oo Oxdaee dos-eee SAS BGS OWN ie ers a oe lapel eee rercre Ce Neoeestne 32 Ra eee a ese eens | BY. lesaCkousse 2 COssobe ANTE NS ol nese Sone ese laliecee 3G 3 |e Fa | ese el sees Bl ts scClOnencs Ad Oke PN 2) eee aimed ree eS eee eet ZS eerie Saal agai = SRI Sold? Gd) didlbye dlls | AK 8) ooo Sesusdsllogconcacce Oleic Se D3 Wes a eae | eee BY) oonCMsoaes pedo Aug. 4] Aug. 12 | Aug. 25 6 DAS | Rea ss 8 13} | Gl AQP sad Osecee =EGOe ans Aug. 6] Aug. 13 | Aug. 26 6 205s ome 7 13) S52: Ale | eee dOne- SAC Ws5cce Aug. 8 !...do. Aug. 25 6 PAS) lise cow's 5 12) |) &il ADT ead Oseeee = (LORE MUS Ss OnE Oke hess| ae eae GO: | eee 29 ANA see sares| eentcee ASS | San does SECO LS ee lh MUS relia sears eae etal eee tara ereret (ahs Eee Bon lc | Meee oe | eee AVN aol 7 NW dfibdly 7? Ika} || seks, I) || a osaceacleaaosuuaes Gulesereee BAUM ees Al esose seccad AGE ped Ose eee Sad O2eeee BO saya Sc aconcess eons Ia GHizes te P10) eee snes (Sscaes AGh|PasdOseee= SILO wae S| ASICS aS | eee ep well cee eee eee Gs Bao ae Sil ade Sel ae eee ATG PAA O=eee ssdOri ane SE (GMO ees el Wee Petraes Peal ee te rt OR iesenae BIS Mueaeuliscassolsocsde 48 |...do- ..-do. POP ieal pact satanic teas (Oi setae SL OS aoc eacies eee 49 |...do. LE GOs esos | AUS al See ayes cate racers | eeepc OM osece Boule hat ES tees peer XM We ooGkosasse PO KO eee tee a) keane! L/S ie oisiy ye 6: c= se38 BH Beeeetel laa aces ounce SS ClO. Edoreyscllace doen eee Eee Oa eine SDu|o Beer! Sse al eee TaBLE XXIII.—L ve cycle of the first generation; summary of Table X X IT. Feeding of— Incuba- : xy Incocoon}| Pupal Total tion. fare ee as larva.| stage. | life cycle. larvee. larve. Days. Days. Days. Days. Days Days. VAWCTAC Creche sociation = eis siecsie eer 6.37 24.7 28.9 6.0 14.5 51.5 Maximum aia eee ee ee | a 31 45 11 18 63 Marni rao a ee eee eto | 6 afarensis reed ea 2 12 43 The results of these experiments are given in Tables XXII and XX. Although limited in number the results of these experiments agree very closely with those of the previous experiments for the separate stages, namely, the life-cycle experiments averaged 51.5 days, THE CODLING MOTH IN MICHIGAN, Ne and the final average for the various experiments on separate stages averaged 51.6 days. The wintering larve of the first brood, which complete their life cycle the following spring, have not been included in the considera- tion of the life cycle of the first generation. THE SECOND GENERATION. SECOND BROOD OF EGGS. Length of wncubation.—On an average the second brood of eggs (Tables XXIV and X XV) required 7.5 days for hatching, which is one day longer than was found necessary for those of the first brood. The maximum length of time for incubation was 11 days, the mini- mum 6 days. The red ring became first visible from three to four days after egg deposition and the black spot two days before hatching. TaBLE XXIV.—Length of incubation of the second brood of eggs laid in rearing cages, Douglas, Mich., 1910. | Date of— | Duration of— é | None! Egg Appear- | Appear- vation.| deposi- | 22¢e of | anceof | Hatch- | Red | Black | Incu- Serion red black ing. ring. | spot. | bation. ring. spot. Days. | Days. | Days. I ACen 2 BAU Cee con eA eS TOM Anos 12 3 8 10 I || se KOY £0 OssosclloacClOuse sal) AIS 115} 3 8 11 = 3 | Aug. 3 doles Aug. 9 | Aug. 11 2 6 8 4) Aug. 4] Aug, 10 | Aug. 11} Aug. 13 6 7 9 i ocsCOsages|a0CO 20s ooas|| Jie, Ald! 6 a 10 Gye BeAR UT ees 5 [Sie evarerer se faa seyere re rats Peek When cllodmaneesl eaomoeae 8 7 | Aug. 7} Aug. 12] Aug. 14 | Aug. 15 5 7 8 S foss@@séo 6 slleeaClscaus|lscn0Oue Aug. 16 5 a 9 9) Aug. 8 | Aug. 13° |...do..- Aug. 15 5 6 Gi LON eeados OSs EaGoe Aug. 16 5 6 8 11 | Aug. 9} Aug. 12 |...do. do 3 5 7 12 do oOo. ado: Aug. 17 3 5 8 13 | Aug. 10.| Aug. 14 | Aug. 16 do 4 6 7 4; Aug. 11 |...do.. dos do 3 5 6 15 do ed Osea sd Os Aug. 18 3 5 7 16 | Aug. 12 | Aug. 15 | Aug. -17 do 3 5 6 17 do do.. -do:. Aug. 19 3 5 7 18 | Aug. 13 | Aug. 16 |} Aug. 18 do 3 5 6 19 COse5 Sallese@lOscs callscoGkoe Aug. 20 3 5 Uf 20 | Aug. 14 OWsseccllass0l@:- do 2 4 6 21 ug. 15 | Aug. 17 |} Aug. 19 | Aug. 21 2 4 6 22 do CMs56cl]secCWsce Aug. 22 2 4 7 23 | Aug. 16 | Aug. 18 | Aug. 21 do 2 5 6 24 do s2aOlOs,. moss Aug. 23 2 5 7 25 | Aug. 17 | Aug. 19 |...do... do 2 4 6 26 do 5 55040) a= dos Aug. 24 2 4 a 27-| Aug. 18 | Aug. 21 | Aug. 23 do 3 5 6 28 | Aug. 19 | Aug. 22 | Aug. 24 | Aug. 25 3 | 5 6 29 | Aug. 20 | Aug. 23 | Aug. 25 | Aug. 27 3 5 iq SO eis Al lle eC Seo orleans do 2 4 6 31 GOS eee lee Go: ..do. Aug. 28 2 4 7 32 | Aug. 22} Aug. 25 | Aug. 27 do 3 5 6 33 do.. ..do =do! Aug. 29 3 5 u 34 | Aug. 23 } Aug. 26 | Aug. 28 (@) 3 5 6 35 do edo: { uo) a to) uw uo} 5 Te 8 | 3 r= Beiiles a 8 n tole) »P 7 n toYo) ~ I Q a0 ~ = ro =| e045 Po 2 q 0045 oo ° =| Q0+5 oI + oo fo) (o} = qe O° poy =I aa [o) S Ss SS esa) cs SE Sa SoS SE 2 S ~ ac inet 5 ~ at Pp . ~ as mb io) 3 rb) os) () 3 oO 3 ° fos] oO 3s A a0) 4 =) Z an) 4 A WG an) 4 A 1 { Aug. 15 | Sept. 12 28 |{ 28 |} Aug. 19 | Oct. 1 43 || 55 | Aug. 24 | Oct. 1] 3 2 do Sept. 13 29 || 29 | Aug. 20 | Sept. 24 355 | 565 seadosssa4|eead oe 38 3 dors do.. 29 || 30 |...do... do 35 |) 57 do.. Oct. 2} 39 4 do do 29 || 31 | Aug. 21 | Sept.. 15 25 || 58 dors... |=2-d05- 39 5 do Sept. 15 ile ||Po2 meen Ofe Sept. 20 30 || 59 | Aug. 25 | Sept. 15 | 21 6 | Aug. 17 | Sept. 20 34 || 33 |:--do:..--| Sept. 20 31 |) 60 do.....| Sept. 27 | 33 7 do Sept. 24 38 || 34 |.-.do.....| Sept. 22 32 || 61 do.. Oct sist 8 do (0) 38) Waon|e-=d0222-- |e Septa 23 33 || 62 | Aug. 26 | Oct. 2} 37 OR ieeed owe Ocha 45 || 36 |...do..-..| Sept. 24 34 || 63 |...do.. Oct. 31] 38 10 | Aug. 18 | Sept. 23 36 || 37 | Aug. 22 | Sept. 12 21 || 64 do... se dOs== 38 1S Eend ore =s Sept. 24 Sie ||P 38h pas OF= ae eee Retest 2ileal oo Goa 5) Ores 4) 12 do do 37 || 39 |...do. | Sept. 23 32 || 66 | Aug. 28 | Sept. 24 | 27 13 do:-=.-| Sept. 28 41 || 40 |...do. Co) 32 || 67 on Oct. 31] 36 14 do Ocienae! 44 |) 41 do do 32 || 68 |...do... “460555 36 15 | Aug. 19 | Sept. 12 24 || 42 |...do.....| Sept. 26 35 || 69 |...do... LEdozse 36 TGE\es-dOre gee dors. 25), 24.1143 Ane 23 Sept. 223 315) 70m doles Octal aod Wile dO=eese SCDiLylo PAG MP eee alee sasllsanCO. 454+ Si yh 7a do SGOES 37 18 |...do do 27 || 45 |...do. Octal 39 |) 72 dole Oct. 6] 39 ISTiE==do Sept. 20 32 ||| 46 |. ..do- do 39 || 73 do.. eons 39 20 |...do 0) B2 At |e eados Octa73 41 || 74 | Aug. 29 | Oct. 10] 42 PAL Ne SAClonss do 32 || 48 | Aug. 24 | Sept. 21 28 || 75 | Aug. 30 | Sept. 25 | 26 9) |e coo s|| OCs Al 43 || 49 Gols |asepta 23 30 || 76 Sept. 29 | 30 PES Nee OlD do 43 || 50 do -do...--| 30 || 77 | Aug. 31] Oct. 4] 34 24 |...do do 43 || 51 do.....| Sept. 24 Sa we Os Oct. 61} 36 25 |...do do 43 || 52 do Sept. 25 S259 |zaaaors do 36 2B ea56 Osc do 43 || 53 do SAC Ores 32 || 80 | Sept. 3 | Oct. 1} 28 7H Wes One e do 43 || 54 do aGlOesese 32 || 81 | Sept. 4] Oct. 6) 32 IAVOTA RO = Sok Ree ein Sere ee este tec ee Sec or gg trey Seas EEA mtn a et ea 34. 2 WiGbobedbhetl 585595 oan 55 536545 oases sedan ede 38S ooo SAS Sy aceon SSS 5552 45 THE CODLING MOTH IN MICHIGAN. : 95 TABLE XXVII.—Feeding period of second-brood larve; summary of Table X X VI. Number| Days | Number| Days Number | Days of obser- of of obser- of of obser- of vations. | feeding. || vations. | feeding. || vations. | feeding. 3 21 5 Bil 6 39 2 24 il 32 y 41 1 25 2 33 2 42 1 26 3 34 7 43 3 27 3 35 1 44 3 28 6 36 1 45 3 29 6 37 4 30 6 38 81 | 2,770 | Length of feeding period.—In Table X XVI will be found the records on the feeding periods for 81 individual larve of the second brood. The average length of feeding for the total number of observations is 34.2 days, the maximum 45 days, and the minimum 21 days. As is to be expected these results are much higher than those for the first brood (compare with Table X XIII), since at this time of year a much lower degree of temperature prevails, and more feeding may be neces- sary for the hibernating larve. Figure 8 (p. 26) shows the jar used in the rearing of codling moth larve. Time of leaving the fruit—The Saugatuck band-record experiment of figure 10 shows that the earliest mature larve appeared under the bands August 30, and that larvee were collected more or less abun- dantly throughout September and the early part of October. The almost total absence of larve during November was to a large extent due to the scarcity of fruit, and this condition materially limited the number of second-brood larve. TaBLE X XVIII.—Band-record experiments, Saugatuck, Mich., 1910. Bee ieee eles) els, | f \ecl#sl8.l8alae 5 oD ES Sl Sed sh en | Ss I) nm) a =/Ss|/ 5/85/34 Seeger les SSeS SSeS leo S| Sa | = [sala sai ea ac S) 2 =) S 6 |asil 6 2 ° | © o |3ss8 S 3 Soils tor. |'o lo se iS a O'S. On hoe Iowa | ois Paeeeeda (212 \4 fe ||2 | A 14 ia |4 |2 ia. |e | | | 1} July 13 6 | eee eee Ws | 1G eet Sep t-cl2 5 ted 3 loa toe [atk Berl 2) -taly 47| 44 | 344....-1.-..- aes Tail) 92) Sept. 15 |. 048 |te2-|-cscn | 25) 37! “0 Boledmly 20-12-28 | 10'|_.... oedipal eos | pce piesa On| oee ell tne Oss ouleu7 dalevaty cote Sait 199) 13). 1 jz... -| 18,\. 24 | Sept. 21,|126 |...--|--.-- 6| 2 \t18 ieimig one) 25) 2) 5 | 1 20)\| 251 Sept ot | 116 |222- |. . Te fea | 5 Ciiaiyeso a5 | 21) 1) 2) | -10)|| 26 | Sept, 27), 10 |-2.--|.2-.- ale Sales gale Auredaleps:) 33.) - 2 | 3 1s... 2 ie 27eal) Sepie30 |u|. 2o--42 22 5 le eo eipeeratest | 30] | 8) a | tai] 88] Oct. 3) 22 |. <2. f2 st. Dissee bes Ol wep 49 | 33)| 1 | as ].__:. G7 SOW Oats soils Utd Bek). Seale ee Oa ae t0| 97 | 8.2... ik asi TAL ae it Orera 3) || ees ees teas ioe 180 dd | Awe: 13°].36 Di ase Dae Peeeel 8 || sh Oecte 12 Qe tee eters yal eee 0 Hl Mae AG 132 1 Fe Rees Sl: S21 Celis Tq) ane Ran eee Bale ee 6 ios | ga 193] 28412. | 82 ivy es Giildesse Oct | poy oe |e ialeeeee 3 Pe Arg 220) 35.|_.--.|----- Der eee | 7 Ai) eee | Cro e| s e 3) loti wal teeteMae 255\6 O32. la... Puli cdi| = ABA ab Oct: 28 Bes. - s/o. 22. ioe 1 Te Bal AND eee Fat a VW ee eee 9 2 3 36 | Oct. 28 D Ale wee | Buy. | ies Oe gs peg IP Secure dk Ae OAD al eee 11 1 OA Re Orca Dsl) 220s ee.) asaee lasses [----- 0 dREUSEpb ss | 8 |o..2-|.- 2. Baleeoe leer eeSSulNowem On| 0272.2 ESI, | oo Bee 1 TOpSepts 6 | 7 |e cen. i |e be e3h | | oseSepteO 1 17 |2-=.. | Bei oleae Total .| 788 | 201] 8 | 313| 29 |237 | | } 112 larvee escaped. 26 ' DECIDUOUS FRUIT INSECTS AND INSECTICIDES. BAND RECORDS OF 1910. The band-record experiments form a very important part in the study of the life history of the codling moth, and constitute at present the only safe test of the development of the insect under natural Fic. 8.—Cage used in determining feeding period of codling-moth larve. (Original. ) conditions. When carefully carried out these experiments furnish indispensable data on the relative abundance of the first and second broods of larve, time of emergence of moths, parasitism, hibernation, etc. (see Table XXXI), and yield in addition an abundance of material for laboratory rearing experiments. THE CODLING MOTH IN MICHIGAN. 27 TABLE X XIX.—Lake Shore band-record experiments, Douglas, Mich., 1910. ab on than [exe Pos Oh me pitas pane ileonenliees - 2 fe es) | er re SO peal Set | Bae 2 [eo ja ‘te . 2/8 |els |e (3 le [Beis] 2 sls la [8 12 138 3 2. > 1g -[S-|g9 -18 -|sel| $ art SOLS soy Us ell Wee in ee sb ‘s =) oOo] ei “188 =) S sb a Sy || IES tet | eS) tet me = S38 = os aS a> aS Soe 2 = 9 = S|) 45 S So | so = o- we |otlam|onl wa] agli a on = los leSiss lS tac eh tate 2 2 er aoe iio tee < S i |38 3 3 So |o 3 3 Sell IS aeia | eee 3 Se 3 eS) e) aS. A, a Po een (A pee eb, A FOG: VA ha Pa eS Ft ig Re oe oo tao es a es gs ee ae el ee een Sea gs} 119 Pet) AVS La La Ie 18) | Saad een (eee) ee S22 Pepe. 19s) 155) ae | eee | 8 ae! 3|July 18| 40| 28] 2|.....1..... | 10 || 25] Sept.22] 8 |:.-.J.0.., ies Mee 5 A tulye et Se FE | Ae foe, PP AO 26: Sept 2h taeda: ca: EB. 346.9 Riledolys 24 p45 Oe bo 4 IE 14: ||. 97 (Sept.28 nee eee Seep Peas 5 Ginnie ars Fa ISIS | 28 Oct. Vp ob. Polk Sie a ae: MesaesO hess | eh e let 5 | 99 | Och. -4) bbe. cae ears 0 8| Aug. 2] 42| 28 5 7A pesos 21-30 Oct. .7 S| 2aeee [eee 4 1; 0 nek aeenOele Dashes AG DIE Erol 31 1 Oct. 40 |. O fi. 2 eG ee ieee 0 10H Ae Sage no eS ea tees o 25-|| 39 | Oct. 13). 3/22. pen £5 oe 2 biG ATs Bol 590 Ot. - Se 4a) 617 W393 | Oc. 16) bls: [seca i ae | ea Pa bol JaGreseagt ol sa ral MeO ate AD We ACO n34 | Octs AGN 4 [<5 2) sebee ferece: 4 | red Rte ce ee ee AG eta ta | Oct. 22 ee: 5 fs. 2 8p Le: [Risse Kees 0 | TE Rae 20 fF 50: |e fae. SF eee ei ae |p Oci on be ee ea er ty ares 0 | (PF | ud eae) a 9 | eae RG eta ee ape eke 20) | Bip ke (ene Fy oe [eades | 1Gc) Mae oar IP 400 ihe fod Dear A ES igs (COC aio | 2a.) eee ce es |e Af 0 | ET ee 20) eee bea ae il ...-. RLS ee) |) NON soi aa, 2 UES See siee se-ea et is sept. 1-27 |se=- 122-2 16 3 Sule: AON No woe Gn hoes emit a Se eas 0 | 19| Sept. 4] 24 |.-...|..--- 152 see ome Galle Sir PeNOMR 9 [ha ile eee fees eae petra 25 2 pepe 63). Pepe at iesck 9 1 1 |—— =< ZIG Se pics! ON 1G) a= Sal eee 9 3 S Total .| 985 | 262} 30 | 377| 45 |271 2a Wwseptesta | Or. 3] sees SE) ae |) = Ge | In 1910, band-record experiments were placed in three separate orchards, located several miles apart, for the purpose of establishing better average results and determining as far as possible the extent — of existing variation in the time of development cf the codling moth in the selected localities. These were chosen in regard to their rela- tive proximity to Lake Michigan, one near the lake, one 2 miles cast, and the other 7 miles east of the lake. The influence of the lake upon the temperature over the fruit belt of the western part of Michigan is well known by the local fruit growers and horticulturists and is strikingly shown by the difference in the period of blossoming of apples. This period is much earlier in orchards situated inland and later in orchards near the lake. It should therefore be expected that the codling moth is influenced in its development to a similar extent. TaBLE XXX.—Band-record experiment at New Richmond, Mich., in 1910; larvex col- lected by Mr. Herman Schultz. > | a. 1 = 1 hi 2 = | | _ - [ ic , | aie si/2 18 12 |s .|/ssi cd Bese fal cht ed ea pe 5 218 |ssi8 |sdig2]] 3 | | £18 |ssis |aalee © | Dateof | & 2 -|Fa}e -|AS}8s) 2 | Dateoi | = |S -| ears Saks 3) S S =| Sx | ai|sol] oO | = ES 4 Shasl = | Sem po eeulecias st ee ee as | ig |] Py collect- | = | Sie ~| a | Son | a S ing. oS | om 2) o=| S\ae|| 5 ing. S$ |om/ "Sion |"Slias > : ‘ Festi hae oy foes : . Z =| . 3132 (Si) Sy Sou}o on (Serta | mek, i) So | On i) Om | o — Zz | Bie ia le |a les 2 Policia Ao leas Wistalyeth ia} 12 | 3 lo .. jeneme IAA TG Aem(25 PS fos Ile as 1 2/ July 14) 55 | 27 734 oes | eee 26 || 17} Aug. 28 Rasen has Gobir Bie Soiity= ta 60| 20} 7 1422 1.20. PaAOs lentes Aree ah tie ate | 225s} 5225: Opin er Ors Ae tribye yp sie |= 24 j= 4 | 18 | loclSstetOsluSemtara} (29 toe .|- 22 (3) ele be Oo eal Sagulyerr net 20+. 3] <6 122. -| Die easeSentasGe m7 225.| 500: SUES. 4 | _6| July 26] 50] 17 8 Guo se3 19 || 21] Sept. 9 ( )sesd shes CG je ae 7} July 29}; 33 9 = 7 aa ae 1Gal 22 eSepte 12 bo TOep ss ee Dfle As Re Memos ess | 47+ 1 | Th} et (8) 23] Sept. 1} 15.|_....).°.-- sie 0 | gauge! 451622 |- 3" |. ==. ae 8 Sad oe Sse i Sepieds |¢ YOu. -2 24) 22: re ok i Pxrg a tO Adie 7: | 15a Df es One te eal soo Septet 96 je... 253 - Fo) | fi) tye 6s ene i oe ee Sir i ee Sb ld226 hiSept: 24 te 23). cre Doli tas 1 Peas Wat) 15.) Lie Fi OR sSepts:27 25.1 Se ot pak PeateAne se t6 |. Th ss. [eters 5 dle Deon iSepesaO | kepsce fia) Til sees 1 Peamenpentg | 5 f= oe ate: 1 || - - — =a] 15:| Aug. 22| 9 |.--..|---:- Pes. 0 | 543 | 153 32 | 137 | 10 207 | 1 4 larvee escaped. 35215°— Bull. 115, pt. 1—12——3 28 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. The three band records have been referred to as the Lake Shore experiments located near the shore of the lake southwest of Douglas; the Saugatuck experiments, 2 miles from the lake and northeast of Saugatuck, and the New Richmond experiments, near the village of the same name, 7 miles from the lake. Of these the Saugatuck experiments represented closely the locality of the field station and Fig. 9.—Burlap bands on an apple tree, to catch codling-moth larvee. (Original.) the results from these last band records have been used to supple- ment the laboratory rearing experiments.’ Practically all of the apple trees used in these experiments were old and badly neglected, and none of the trees had for some time been sprayed with a poison spray, so that the codling moth had for years developed normally and unchecked in the above orchards. 1 During 1909 and 1911 the band-record experiments, which in 1910 were interrupted on account of the absence of fruit during that season, were carried out in the orchard on the grounds of the station. THE CODLING MOTH IN MICHIGAN. 29 Whenever possible, winter varieties of apples have been used for the band records to test the extent of infestation of the second-brood larve. This was not entirely possible in case of the Lake Shore and the New Richmond experiments because of the great scarcity of fruit during 1910, so that in these localities summer and fall varieties were used, in pdceaon to winter varieties. The apple trees of the Sauga- tuck band experiments consisted of the following varieties: Three Baldwin trees, one Greening tree, two Golden Russet trees, and one crabapple tree. Through the courtesy of Mr. Herman Schultz, of East Saugatuck, Mich., five of these trees were placed free of charge at the disposal of the station. The apple trees were prepared for the band experiment in the usual way. The loose and rough bark was scraped off from the trunk and main branches. Cracks and crevices and decayed hollows in the trees were plastered over with cement. A considerable amount of dead wood had to be removed from several of the trees before these could be used. A 4-ply burlap band about 5 inches wide was placed around the trunk of each tree and about 2 feet from the ground. Sometimes it was necessary to place additional bands around the main branches on badly damaged trees (fig. 9), but as a rule a single band was found to be sufficient. The bands were examined every three days and the larve collected from each orchard were brought to the laboratory for further obser- vations. The details pertaining to these records will be found in Tables XXVIII to XXXI. Taste XX XI.—Summary of Lake Shore, Saugatuck, and New Richmond, Mich., band record experiments of 1910. Lake Shore. Saugatuck. New Richmond. Observations. : Total. | Percent.| Total. | Percent.| Total. | Percent. Larvee collected from bands.....-.---.-.--- 985 100.0 788 100. 0 543 100.0 Moths emerging: Cn Pee aren Pe ee IE 262 41.0 201 2555 153 28.2 TG 5 2 hae AES Seay es eee anne 377 59.0 313 39.7 137 25.2 TACHI SOT Lee oe See oe ee ees 639 64.8 514 65.2 290 53.4 iIRarasitizedslanvice.o: 0. sccee es. cece ee 75 7.6 37 4.7 42 Wott Winter-killed and injured larvee........--- 271 2a 237 30.1 207 38.1 HWanveno MunewinsbDLOOG se 2228 252-52 - 52 - 860 87.3 577 (BOX 479 88.2 Transforming larve of the first brood =. --- 262 30.5 201 34.8 153 31.9 Wintering larve of the first brood....-...-- 598 69.5 376 G5t2 326 68. 1 Larve of ‘the Seecondubrood@ 22+ 2-2 ase ee 125 NG 211 26.8 64 11.8 On examining the curves of figure 10, showing the results of the band experiments, it will be noted that the two broods of larve overlap and can not be definitely determined from these experiments alone. With special reference to the Saugatuck experiments the hypothetical curves in figure 10 which have been drawn to repre- sent the two broods are based on the following considerations: The 30 : DECIDUOUS FRUIT INSECTS AND INSECTICIDES. last moth of the spring brood emerged July 27; it required at that time of the season 45 days from the date of emergence of the moth to time of maturity of the resulting larva. Thus the larve of the first brood must have ceased to appear by September 10. The first moth of the first brood or summer moth emerged July 29, at which time the insect developed rapidly and mature larve resulted in 33 itt Teta Taare | tH iM eae MTT See i | f | HAHAH HF Pe == —ae -B h = a { === os : — i aaa eS — = Sat ASS SS a aS = eos JULY AUGUST SEPTEMBER OCTOBER NOV, Fic. 10.—Curves made from band-record experiments in orchards at the lake shore near Douglas, at Saugatuck, and at New Richmond, Mich., 1910. (Original.) days. Thus the first larve of the second brood appeared August 31. Similarly, the first-brood and second-brood lary in the Lake Shore and New Richmond experiments have been determined, with due consideration given to the seasonal conditions of each locality. The results from three band experiments may be appreciated by an examination of the curves in figure 10. A difference in the time and rate of maturity of larve will be noted in considering the height of the curves representing the first brood. In the Lake Shore orchard a | THE CODLING MOTH IN MICHIGAN. Si the maximum occurred August 8, in the Saugutuck orchard July 31, and in the New Richmond orchard July 18. It will not be possible to compare the dates for the appearance of first larve of the first brood, since the New Richmond experiments commenced slightly after the larve began to appear. At the Lake Shore band experiments larve were collected in great numbers during the month of August, whereas at New Richmond only a few were obtained. There is only a slight difference in the time of appearance of the earliest second-brood larve in these locali- ties, which would indicate the existence of a tendency on the part of the seasonal conditions to become equalized or uniform over the fruit belt at midsummer. At the Lake Shore orchard larve continued to appear one month later than in the New Richmond orchard. Part of this difference was due to the scarcity of fruit at New Richmond, but also partly because of prevailing higher. temperature during the fall near the lake, which prolonged the season in the latter locality.! Though limited in scope, the results of these band experiments show that the codling moth varies in the time of its development in these three localities in close relation to existing climatic conditions, thus indicating that the insect must be governed by the same climatic con- ditions that govern the plants, and it must be due to this fact that we find a corresponding difference in the time of activity of the insect in the spring, as is noted in the time of blossoming of apples in the different sections of the fruit belt. Of the total number of larve of the Saugatuck band experiment 73.2 per cent pertained to the first brood and 26.8 per cent to the second brood. Of the first-brood larve 34.8 per cent transformed the same season, and 65.2 per cent wintered in the larval stage. Of the total number of larve, 25.5 per cent developed into moths in 1910 and 39.7 per cent in 1911. Parasitism by Ascogaster carpo- capse affected 4.7 per cent, and 30.1 per cent died during the winter, killed by cold. SUMMARY OF SEASONAL-HISTORY STUDIES OF 1910. Figure 11 represents graphically the main results of the seasonal- history studies of 1910 and can better be appreciated from the diagram than by description. Except for the prolonged pupal period during the very abnormal spring of 1910 the insect developed fairly normally so that from the point of view of the activities of the codling moth the season may be taken to have been about average. \ 1¥or a more thorough test, records should be taken on temperature, time of blossoming of apples, and time of emergence of spring brood of moths in the different sections in the fruit belt. 32 DECIDUOUS FRUIT INSECTS AND INSECTICIDES.’ SEASONAL-HISTORY STUDIES OF 1911. The results of the 1911 life-history studies of the codling moth are in many respects similar to those obtained during the previous year. (18UIslIO) “Yow seisnoq 4e ‘OTE, Sulmnp poArosqo sv Your BUI[pOd oY} JO AIO}SIY [eUOSvOS O}VINSNIII 04 WIeISCIG— IT “DIY | 2 || Gace a OL ore Gh Ch. CZrOcmC molmG 6Z Oz Sols GZ OZ anoles YAEWSAON| YAEOL9OO HSIW 31d 4S ISNoOnVv ails SIN IMUE ATW The main difference is that found in the time of transformation and date of appearance of the different stages, which is ascribed to the prevalence of a very unusually high temperature during the spring PR cm ery i THE CODLING MOTH IN MICHIGAN. 83 and summer. To a certain extent the 1911 life-history studies con- stitute a test upon the 1910 investigation and in addition show the behavior of the codling moth under the above climatic conditions. In the presentation of the observations made during 1911 on the codling moth the same plan has been followed as for 1910, and many of the details concerning methods and tabulation previously described apply equally to the 1911 studies. TaBLE XX XII.— Time of pupation in the spring of 1911. Date of | Number || Date of | Number || Date of | Number |} Date of | Number pupa- of | pupa- of pupa- of pupa- of tion. pupe. tion. pupe. tion. pupe. tion. | pupe. May 9 1 || May 22 10 || June 2 2 || June 14 3 May 11 1 || May 23 8 || June 3 2 || June 15 1 May 12 1 || May 24 8 || June 4 3 || June 16 1 May 14 6 || May 25 7 || June 5 5 || June 17 3 May 15 7 || May 26 5 || June 6 4 |) June 19 2 May 16 2 || May 27 8 || June 7 2 || June 21 1 May 17 8 || May 28 9 || June 8 2 || June 22 1 May 18 12 || May 29 6 || June 9 7 || June 26 1 May 19 16 || May 30 7 || June 10 6 May 20 14 |; May 31 11 |} June 11 4 May 21 11 |) June 1 3 || June 13 1 Total pupe, 212. SOURCE OF REARING MATERIAL. The rearing material in the spring of 1911 consisted of wintering larvee, which in a normal way had entered hibernation the previous season. Practically all of the larvee were from band records and represented the normal proportion of both first-brood and second- brood larve. The wintering cocoons were made between narrow strips of wood (fig. 4) and in pieces of corrugated paper (fig. 17). During the winter larve were kept in an outdoor shelter. WINTER-KILLED LARVZ. The percentage of larvee killed by cold during the winter proved to be equally as high during 1911 as observed in 1910. After the com- pletion of the different band-record observations the results show the following percentages of winter-killed larve: Per cent. Nevehiehm onc sbamdereCOnds sy. 16 ane ate nonin eae ook slhetterne 38.1 Saugatuck band records..... Pr reese batt ec ane te as. mene 30 rice Sinoneuamld meCOnds=. of eee ee Soke ee es Difd From these figures should be substracted a small number of larvee injured in the course of transportation from the field to the laboratory. Those from New Richmond showing the highest percentage of mor- tality were sent in boxes through the mail and suffered more or less under transportation. The larve from the Lake Shore and Sauga- 1 During 1911 an improvement was made in the method of shipping the larve from the distant localities of the band records, by the use of mailing tubes (see page 61 and fig. 17). 34 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. tuck orchards, however, were all carefully handled, and the results of these observations show approximately the normal proportion of winter-killed larve. SPRING BROOD OF PUPZ. Time of pupation—In the rearing cages pupation commenced on May 9, reached a maximum May 19, and terminated June 26 (Table XXXII). The relative rate of pupation is illustrated by a curve in figure 12. It will here be observed that pupation occurred rather irregularly and that the time when the larger number of individuals pupated extended over a longer period than in1910. This, of course, had a direct bearing upon the time and rate of emergence of the moths of the spring brood, which, like the pupz, appeared very irregularly. TaBLE XXXIII.—Length of pupal stages of the spring brood, Douglas, Mich., 1911. { ly | | No. | Pupated.) Emerged. Days|| No. | Paperedil Emerged.: Days.|| No. | Pupated.| Emerged. Days. | 1 | May 14] May 29 15 42 | May 21] June 10 20 || 83 | May 29 | June 19 21 2 dors Gon s-= 15 43 adosnas June 9 19 84 do soe ae 33 lee OK ce | May 30 GH ee doi June 10 20 || 85} May 30 | June 20; 21 4| May 15| May 28 13 || 45 | May 22] June 14 23 || 86 dor June 18} 19 5 Opus | May 39 15 |) 46] Once sc June 11 20 87 doses June 19 20 6 | May 16 doz Ea peel’ eae Reass June 10 19 |} 88 | May 31 | June 21 21 7 dol 2: June 6 21 || 48 do.....] June 9 18) ison | Esa os doi 21 8 | May 17| June 2 16 49 do.....| June 10 £95 S90c teed oseeae June 20, 20 On| Aedostes= June 3 17, 3}\>_ Ov EM y-93 |e eado see: 18 Ole |= downs June 19}; 19 10 doze jeeadosere.: 17 || 51 dome: slsnedorms® 18s 922 doses. June 20) 20 11 SO Ose e| Lune ao 24 | 52 ed Osos June 11} 19 93 | June 1 ac Koa 19 WA es ee Se June 2 16 53 dowres June 10; 18 || 94] June 2] June 22 20 13 | May 18} June 3 Sf Geb Mey OAL) Aibine G) AB He Gs I= Geo. June-21} - 19 14 “Gloyseac dose 16 |} -55 20K). = = June 9 16 || 96 | June 3 | June 22 19 1155 SACI eo = June 6 19 BD |lsoeO.Onsaad June 10 Ae Qi |eeeaosse2 June 21 18 i6n|eeedow=: June 4 17 Bins sdOseee June 11 18} 98 | June 4| June 23 19 17 GO==2o.| Juanes 18 Salsa GOrse- June 14 21S 99 se Oseeee June 24 20 18 dor June 4 17 59 dose June 11 18 || 100 | June 5 | June 23 18 1972560 OSeeee June 5 18 60 | May 25 | June 12 135} 10s | Sa edoreass doses 18 20 | May 19| June 6 18 Gla ==doke=- June 14 20 LOD Ee =dosaess June 24 19 21 E@OeEEe June 5 17 62 do dorees= 20 || 103 donee: does 19 22 KO se ealeaeG Resor 17 63 KOO Sas June 12 18 || 104 | June 6] June 23 17 23 |...do (exon aes 17 64 {72 -done es June: 14> 120) || 105n|keidoss= June 24/ 18 24 “G54 < Sedo: 17 65 do.. June 12 18 |} 106 | June 8 dose 16 25 dor June 6 18 66 | May 26 | June 16 21 || 107 | June 9 | June -25 16 26 doveee- June 4 16 |; 67 O:525 June 15 20 |; 108 doseze: June 27 18 Sado we June 5 17 68 do.....| June 14 19 || 109 doit June 26 17 28 bead Oren June 6 18 || 69 doses AOD ee He ay ata do Gottee 17 208s 2sdor.-5- June 4 16 || 70| May 27 | June 15 19 || 111 | June 10 dou 16 30 ed Ofte June 7 19 71 Ol ee June 16 20 || 112 doze June 27 17 31 AGO Soe = June 6) 18 72 doze June 19 230) | abis See Gosaae Goes 17 32 | May 20| June 9 20 |S 5 |e= 5S 16 ae S 15 Jas 14 715 & 13 i a 2 69 8 nes = + a. 1° 63 @ & q auauang? oe 20 SS 6 + Ef S5 i.) : ae) ae} w ; 54 = E i 5 3 Zo te 48 | ie ony 4 ies 2 4 34 : _ = 1 i Eye “E @. es ese rae re er Selomi7aIqizii2s22502 7024s im 4 it Gen OyslOnN Zing Ibm eN 20s 22024 2b yee SCh et mas NEY, 2 June Fig. 12.—Curve of spring pupation of the codling moth in 1911, at Douglas, Mich. (Original.) The results are given in Table XX XIII and are further summa- rized in Table XXXIV. The average length of the pupal stage was 18.4 days, the minimum length 13 days, and the maximum 24 days. Relation of temperature to the duration of the pupal stage -—From general observations it has long been known that the temperature has a marked effect upon the duration of the pupal stage. The intimacy of this relation has already been pointed out by different investigators and most recently by Prof. E. D. Sanderson in a paper on the relation of temperature to the growth of insects.1 In our tentative effort to find the existing relation of the tempera- ture to the length of the pupal period at Douglas, Mich., the average temperature has been taken from the average daily temperature 1Journ. Econ. Ent.; III, p. 113, 1910. 86 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. during the pupal stage of a number of individual insects. These averages were computed from the temperature records of Table LXX, which are from a self-recording thermometer of the type used by the United States Weather Bureau. The instrument was regulated in accordance with a mercury thermometer and was kept in the rearing shelter throughout the season. The records in Table XXXIII give the date of pupation and the date of emergence of moths for 122 individual insects. ea cit I Temperature. a Fig. 13.—Curve showing relation of temperature to the duration of the pupal stage in the spring brood of the codling moth; Douglas, Mich., 1911 (from Table XX XV). (Original.) TaBLE XXXV.—Average daily temperature during the pupal periods of the spring broods; summary of Table X X X LIT. l | | Average mean temperature. | Average mean temperature. ; No. of | No. of | pepe obser- | Papa obser- | Perio“ vations. | usenege. | Maxi = Mini- | P&TIOC- Vvations.| 4 verage,| Maxi- | Mimni- | mum. mum. ts Cre) ia: mum. | | } | Days. | BOIL Wane es ele Days. OTH sar is nae OF 13 3 68. 31 69. 86 66. 02 19 23. | 65.84 | 67.29 64. 48 14 Za ih Floyd! Tie TT 69. 06 20 20 | 65.65 66. 81 64. 53 15 4 |} 69.19 70. 08 68. 83 21 14 | 65.01 67. 58 64. 49 16 12 67. 29 68. 56 65. 51 23 | 2) 4659331) "65261 765505 17 18 67. 32 69. 29 66. 06 24 | 2 69.52 | 71.73 67.32 18 22 66.50 68. 23 65.26 | | Observations on the time of transformation were made once daily and invariably in the afternoon. In Table XXXV a summary of these temperature records is given showing the averages for each day and also the number of individual pupe under observation for the THE CODLING MOTH IN MICHIGAN. ou respective days. To show the extent of variation in results obtained, the maximum and minimum of average temperatures of individual pupal stages are given for the different days in the same table. On examining the diagram of figure 13 it will be noted that where the averages have been made from a large number of observations the results are fairly uniform. These results here show a marked de- crease in the time of the pupal stage with an increase of temper- ature. Considering the curve of this figure we get the following readings: a °C homme lord aysapulpalastage. wera. sos ) iS WwW Oo = a) Z. yay uadue | “ unypeusduias wep abeuany Brrr aeanece SUR GOSS RCAC USRSPASSSS SSURAASSSease 27 29 Si OHIZ Tae lem 20 22a eG brs ON ee May June HU Fig. 14.—Emergence curve of moths of the spring brood in 1911, at Douglas, Mich. (Original.) been due to the fact that mating had not taken place, it being difficult to find the insects in copulation or to bring about mating by confining together single pairs of male and female moths. In the stock-jar cages, where a number of male and female insects have been confined, eggs have always resulted in abundance and mating must have occurred quite generally though it was only observed on rare occasions. It was therefore planned to remove female moths from the stock jars after the moths had been confined together two or three days, and prior to any egg deposition in the stock jars. 5 tannic THK CODLING MOTH IN MICHIGAN, 39 TABLE XXXVII.—Egg deposition in confinement by individual moths of the spring brood, Douglas, Mich., 1911. Number of individual moths. | E iL | i | 3 | 4 | 5 | 6 dé | 8 | 9 | 10 | 11 | 12 Date of egg dep & Date of emergence of moths. — = S S = =H To) a) Wo) x bal Jo) mo tom N N N N N N N S S = 2 = S S 2 2 2 < = Seipslseie sees ee ost fe le Sole toa 8 a e la) lard an) a e me a > = - une wl Onin |e PAG} eset cl fal Ss ol b Aaa | ES UE le De ans Hee cme) ena onl NY etees June 11 1 TDS cep teed (Fk ee aE Sp 2 |S ge rer eae Fee ge (Ree ere erm amd betes eae Beit ee Uh ees | eee | a ey el eecegera ote 2s A yeeea ecisb| ee neee clr eds ct Neri ee a ale HUTA! Uses es ere senceal lee celal Sree oe lees eral RS ere ae) lene aeectoeatel [ae vee ee Vege cs [ean ec Pa Afiobaes= IM lal Seale ee (aaa jooeesdisss-s5)/soesea/se5 ee /255 S58) Sosueslosenes|Aoashdllooka Afibnaey dG Nie eal aes eee | reset Bis el [ Meken tel Resear [eas al Lene ati] ear ate eee a ete ATT UG) Nees Se elle eevee eee ee ee es Ae) [are eee be pe | Te Van peg | ee Pea Wea ae Vereen Aybaavey, UZ it eae ee Es = ol Ete ere 1 BS a ee ee ae hel ee Pe ee [ieee Mere ee a eee June Sl Ole | ase sls 8 Aree es Das esas 2A etary Rn Wieser oes | eee ed Ngee June 19 2 DS Nee eke G OC | asa | eee | ace eens (ieee ee June 20 Daal eer one (ere ere 20 Ha tl | Hee | PSE SS a Fa [ahaa ar le June 21 7A) ey see Sets Sl eee ra al eRe ees Farce aid Fe ie eal lees ene eed ees Bee [eae ee a June 22 phate | eect Wiese Neal [aeons eet eee | caer Fe pila et arya Cg Rees ee el np June 23 Tig eee Ne eek ee | eae fe eee Ea Yel [ese ees pail lees ete Ha eyteweneel [ey eee eer tLe ae (bine 2X4 || oe ale Ss Se | Seelaes at ee Beaess| em a ah | ee ee Tyce ye oe | eee Aoranes Pa |) eae SSS |e ee ee ae el Pee DG Foal ee 2 | ee ee 0 ea | ee | ae 4 June 26 BS Alas Ste Te fee Nae [i Narr Fe a yt ie | eye Pear ee Re | eee BUT ae ai ae eee ses | ahs ee ee Sean oe see cc ee we eta lee Aa AieaVs): PS Sal ells ee | ee Th et ta eae eee 1 Uy ae Reaper a Nees ae | me Arba yey 2740 it | peeks Sal eet et ate ene fm eee [eee 7 Aoyee fe nee NS} Weaaaoc PAA ees cal (rears ee Tf BYES STO VA ee ce RR 5 2 po Ue (eee A a Pees =e 28 56 (Gel ee eer eeu yaar Spee pee | ere ee lee! Shes ll ee B Yoo |e Rese es [Eee 13 40 Ale Palen JIS Pa Sonal sere ele so eeeel eee Sl beet ea see (eee [arr lia scons LA eevee Sulivegess| eee ee sree see esas lis ee. Sto sees aleeie 32 1 es as eel ae oe irae Sin eae | pre | ass aes | eee | ee Se oa aera eee aes oe alle ee 5 divi. gs aol 2 Se Sali Se Heel poeena phos ac |bauoSe pose 6s asnase |Seere a |e soe |qoscoe 33 Date of death of moths. < Sol So Yen) ‘ Oo S 5 a N el px N N N oO Wo Wo) on) (eve) Pe ear |e oe |e | eee 3 3 3 3 3 3 3 S 3 3 3 eS = = [= Lear} — ES Lar) = Laer) Lor) 1 Escaped June 20. In all 160 female moths were removed from the different stock jars (Table XL) and were kept isolated in glass tumblers, covered with perforated tin covers. A small piece of sponge dipped in diluted sugar-and-honey solution was inserted to supply food. To encourage egg deposition fresh pear leaves were placed in the tumblers and were daily replaced by fresh foliage at the time the tumblers were examined for eggs. TaBLE XX XVIII.—Zqq deposition by individual moths; summary of Table X X X VIT. Number of individual moths. Observations. WA 22s 3 4 5 6 7 8 9 10 11 12 Total eggs per female ...-.-. 70 35 26 36 | 161 35 32 86 | 102 49 15 38 Days before egg deposition . 7 iG 4 6 6 9 4 5 4 3 5 8 Days duration of egg depo- SIGIOM ets oe ae ao Seeee 16 9 1 4 7 3 2 | 2 6 3 2 2 Days alive after egg depo- | SUMO pee eo ecc Soe 5 2 On easss- 2 il 3 | 8 3 5 4 3 Days moth lived......-.---- 27 17 gee ae | 14 12 8 | 14 12 10 10 12 | | | ea ail 40 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TABLE XX XIX.—Egqg deposition by individual moths; summary of Tables XX X VIT and XX X VIII. Observations. Average. | Maximum.} Minimum. Mgesiper fen ales es create ater as ee tee eater era ere 57.08 161 15 IDFA AP GEN oe Wee os ooh eee osase scoceesasodonssceosh See saces 16.31 58 1 Days beforeiegs deposition per females=-2.2--4-------- eee 5. 66 3 Daysiofers depositions pertemales==messeece sees eee eae 4.75 16 I Daysamothsilived afterieseideposibioneas se e-e = sees eee eee eee ee Bal 8 0 Day Sumo Gh Siivie dni tse chai Srna eres eee alee ee ey eer 12.72 27 4 From the 160 separate experiments only 12 yielded results worth recording, and these are given in Tables XXXVII-XXXIX. The following observations are recorded in Table XX XVII: The time of emergence of the different moths, the time and amount of egg depo- sition per female, and the date of death of each of the female moths. In Table XXXVITI a summary of results will be found showing the number of eggs per female, the number of days before egg deposition, the duration of egg deposition, and the length of life of the moths. Tt will be noted that on an average these moths commenced to oviposit 5.6 days after their emergence; the maximum length of this period was 9 days and the minimum 3 days. Egg deposition extended on an average over a period of 5 days. The average number of eggs per female was 57.08, the maximum number of eggs per female 161, and the minimum 15 eggs per female. The moths lived, on ap average, 3.2 days after egg deposition; in one instance death followed the day after the last oviposition; on the other extreme a single moth lived 8 days after the last egg deposition. The conditions under which it was necessary to keep these moths for observation were of course quite abnormal and it is doubtful whether all of the moths deposited the normal number of eggs. It is the writer’s opinion that in the field the average number of eggs per female is considerably higher and may reach an average of 75 to 85 eggs per female. Egg deposition wn stock-jar experiments.—The nature of the stock- jar tests has already been described on page 13. As will be found in Table XL, the observations merely cover the date of emergence of moths in each cage and the date of the first and last egg depositions per jar, which give only an idea of the extent of the oviposition period. We find from these data that on an average the first eggs were laid four days after the date of emergence of the moths. | THE CODLING MOTH IN MICHIGAN. 41 TaBLE XL.—Oviposition by moths of the spring brood in rearing cages, Douglas, Mich., LOT. Date of— Number of days— | Num- From Cage No. bemet Emer- First Last Before | Duration date icf gence of ovi- ovi- ovi- of ovi- < is < t moths. | position. position. | position. | position. pepe position. 1 13 | May 24 | May 28] June 14 4 18 | 21 2 20 | May 29] June 3] June 21 5 19 23 3 9 | May 30] June 10/ June 10 11 i 11 4 10 | May 31] June 6] June 8 6 3 8 5 5s |idamney doe June 9 5 4 8 6 29 | June 2 GOs-=ee ea Giorses « 4 4 7 Ut 39 ; June 3] June 5 | June 21 2 17 18 8 47| June 4] June 8 | June 20 4 13 16 9 40} June 5]|June 9/| June 9 4 1 4 10 43 | June 6 doles: June 24| . 3 16 | 18 WL 29 | June 7! June 10} June 20 3 11 | 13 12 56 | June 8} June 11 | June 23 3 13 15 13 45|June 9} June 12 | June 15 3 4 | 6 14 50 | June 10 | June 13 | June 22 3 10 | 12 15 14 | June 17 | June 22 | June 26 5 5 | 9 16 48 | June 19 |} June 23 | June 27 4 5 8 17 38 | June 23 | June 25 dome 2 Bl 4 18 44 | June 24 | June 27 | June 30 3 4 | 6 19 16el; dame? 25,5 2doss5.- July 2 2 6 | 7 PANY, CT AD Ce teres See seein oie Cease ee 4 8.3 | RS TIVES Se TNT UE TT app ee ere re a a 11 19 | 23 AAs Tey Uae ee eros Se a eee 2 1 | 4 The shortest period before first egg deposition was 2 days, and the maximum period 11 days. Within the separate cages oviposition lasted from 1 to 19 days, with an average of 8.3 days. When we consider the period from the date of emergence to the date of last oviposition we find a maximum length of time of 23 days, an average of 11.3 days, and a minimum of 4 days. Period of egg deposition.—In the field egg deposition is estimated to have taken place from May 28 to July 18, with a maximum number of eggs between June 10 and June 30. This has been estimated from the records of egg deposition by moths in captivity, the time of emer- gence of the moths, and the band-record observations. Length of life of moths.—The length of life of 153 male and 177 female moths, confined in the stock jars, is given in Table XLI. On an average the males lived 9.18 days and the females 10.63 days. ~The maximum length of life for the males was 18 days and for the females 23 days. 42 TaBLE XLI.—Length of life of male and female moths of the spring brood in captivity; DECIDUOUS FRUIT INSECTS AND INSECTICIDES. summary of records of 330 individual moths, Douglas, Mich., 1911. Male. Female. Male. Female. Length| Number | Length | Number || Length | Number | Length | Number of life. |ofmoths.} of life. |ofmoths. || of life. |ofmoths.| of life. | ofmoths. Days Days. Days. Days. 2 2 2 2 14 11 14 9 3 2 3 4 15 8 15 13 4 12 4 6 16 3 16 5 5 11 5 5 17 2 17 5 6 11 6 10 18 1 18 i 7 14 7 A SSH ree Deer erie ee 19 4 8 18 8 A fe ela eaten tae tl NGS ene or 20 2 9 15 9 PA) cali Eh es ass ts es ee se 21 Mt 10 16 10 22 at Sepik ees ee lee tee 23 1 11 11 11 13 12 15 12 14 153 ork 177 13 1 13 3 TaBLE XLII.—Length of life of male and emale moths of the spring brood in captivity, Douglas, Mich., 1911; summary of Table X LI. Life of Life of Observations. male female moths. moths. Days. Days. AVCTAZ CRE Se 2 eee sae mee 9.18 10. 63 We pahonbhinss544 fe eseesunse 18 23 Nbrauboaohonessosksaoosonsssee 2 | 2 It is of interest to note that in this brood, as well as in the summer brood, the females were more numerous than the males and survived the males on an average by about two days. THE FIRST GENERATION FIRST BROOD OF EGGS. Length of incubation.—Observations on the length of incubation extended over the greatest period when eggs occurred in the field (Table XLIIT). The high temperature which at times prevailed brought the minimum length of incubation down to 4 days, against 6 days for the same brood in 1910. The average length of incubation for the brood was 8 days, the maximum 10 days. Observations on the embryological development of the eggs were also taken as recorded in Table XLIII. -The so-called ‘‘red ring” generally appeared 3 days after egg deposition, and the ‘‘black spot” 2 days previous to hatching. THE CODLING MOTH IN MICHIGAN. 43 TaBLeE XLIII.—Length of incubation of the first brood of eggs and average mean tempera- ture during incubation, Douglas, Mich., 1911. 3 Date— | Duration of— | Average een Naso von qunean vation.| ©885- | Depos- Red Black Red |Black| cou) “Cee. ited. ring. spot. Hatched. ring. | spot. ee ature. | Days.| Days. | Days sae Te ase aaa May 28]| June 1] June 5] June 7 4 8 10 64. 27 27 |e May 30/ June 3] June 8/| June 9 4 9 10 64. 21 “4 a) | (Seegeeesere June 1] June 4 dos== June 10 3 i 8) 65. 79 Areca ne June 4] June 7 | June 11] June 12 3 7 8 67.78 | Sewers June 3] June 6) June 10} June 11 3 7 8 67. 87 Gn eee June 5) | dune 8555. * ea unems a [es eee 8 66. 388 7 (sel Bs a ee UME PG! Meenas | See ces 2 doings Weslo es ss seesee 9 65. 07 8 14} June 8] June 11} June 15) June 17 3 a 9 65. 27 9 81 | June 9] June 12) June 16 doses 3 7 8 65. 30 10 ee Ob seese eras Got Se Id pease June 18 3 7 9 64. 96 itil IAG AIIM Ee ROW PME, 138|es = ee | June 19 Seiler 9 63. 68 12 15 do BEOUCE AR AA eee Ae June 20 Sal eee 10 64. 12 13 68 | June 11} June 14} June 18 e) 3 7 9 62. 93 14 20 do =do do.. June 21 3 7 10 63. 58 15 50 | June 12} June 15} June 19 doe 3 7 fe) 63. 29 16 8 do 00 WEaeClo ses. June 22 3 7 10 63. 97 17 31 | June 13} June 16) June 20 One 3 u 2) 64. 50 18 46 | June 14] June 18 | June 21 Goes 4 | if 8 65. 21 19 13 COs | ee dose Oko esse June 23 4 |} 7 9 66. 55 20 51 | June 15} June 19 do O85: 4h | 6 8 67. 18 21 18 doe dots: eed Ose June 24 4 6 9 68. 30 22 60 | June 16] June-20 | June 22] June 23 4} 6 7 67. 73 23 18 (Oeste OWsacae aos = June 24 4 | 6 8 68. 93 D2, kel ee Be June 18 | June 21 | June 23 Ose see 3 3 6 70. 95 25 48 | June 19| June 22 | June 24] June 26 3 5 a 72. 10 26 668 | IIe: 205 | Eas dora lee LOR See June 27 2 4 7 73. 08 27 17 edoss doze | June 25 | June 28 2 5 8 l2no2 28 47| June 21] June 24| June 26| June 27 3 5 6| 73.67 29 18 | June 22] June 25} June 27} June 28 3 D 6 73. 42 30 28 | June 24] June 27 | June 30] July 1 3 6 7 69.15 31 10 | June 26} June 29; July 1] July 2 3 5 6 70. 07 32 52 Beco s|lase dose POCO eee July 3 3 5 7 71.61 33 82 | June 27] July 1) July 3] July 4 4 6 7 72. 51 34 24 | June 28} July 2 /|...do... ed Oe 4 Ey 6 73. 16 | 35 Of WeAfivb ney O40). | eee eee ie | ditiny Zhi dwt, = 6) locsssellscoesc 6 76. 96 36 34} July 2) July: 4/July 5] July 6 2 | 3 4 82.80 ‘TABLE XLIV.—Incubation periods of jirst-brood eggs; summary of Table X LIII. Appearance of red Appearance of Total incubation ring. black spot. period. = Number | ; Number | »; - Number Durer of obser- pane of obser- od of obser- Ol days. | vations. ¥~- | vations. ays. | vations. 2 3 3 1 4 1 a) | 21 4 1 6 6 4 10 5 8 7 6 Shs eee eee | deme ea 6 a | 8 8 ae SE al |S thee a 13 9 10 Cope spt ER eee 8 | 1 10 5 ORE cs Se Reel Ae Sree By | sin eteear a escenario 1 35215°—Bull. 115, pt 1—12 4 pose pO 44 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaBLE XLV.—Incubation periods of first-brood eggs; summary of Tables XLIII and X LIV. Number of days— Observations. For appear-| For appear- For incu- ance of ance of 5 red ring. | black spot. bation. IMSVCTAR CSS eas alae tetera Mera ce 3. 206 6. 161 7. 944 Wieprabanibietsosbobeoecsbe45se 4 9 10 Withee so oe abet cece se 2 3 4 TaBLE XLVI.—Average mean temperature during incubation of first brood of eggs, 1911; summary of Table X LILI. Number Daseiet Average mean temperature. of ob- a incuba- serva- orl : = tions. 2 Average. |Maximum.| Minimum. ° pe 7a of 1 4 S25 SO le io ere ces eas Hl Be rere pene 6 6 73. 04 76. 96 70. 07 6 7 71. 03 73. 08 67.73 8 8 67. 65 72. 52 65. 21 10 9 65. 03 68. 30 62. 93 5 10 64. 03 64. 27 63. 58 Effect of temperature upon time of vncubation.—One of the greatest factors affecting the time of incubation is the temperature. This is fully shown from the results of the temperature records for the time of incubation both for the first and second broods of eggs as brought out in the curve of figure 15. Because of the similarity of results obtained, the two broods of egos are here considered together. The same methods of computing results have been followed as for the spring brood of pupez (p. 10). In Tables XLIII and LVIL the average mean temperature is given for the time of incubation for the different sets of eggs. These data have been summarized into averages under the respective days of the hatching periods. (Tables XLVI and LX.) The curve of figure 15 has been plotted from these combined data, and shows a marked shortening of time under a prevailing high temperature and a pro- longation of time under prevailing low temperature. Taking our readings directly from the curve of figure 15 we get the following average degrees of temperature for the diTerent number of days of incubation: A days—83.6° EF. or 28.7° C. LG days—62h/ 2) be ore lieOenGe D Ck w= 770° 1, Of AIO? C. IZ days—les hy Orono es@s Gdays—72:8> 1. or22.8° ©. Is days—ile2e i SorslonZoa@e 7 days=70.0° F. or 21.1° C. 14 days=60.6° F. or 16.0° C. 8. days=67.0° F. or 19:7° C. 15 days=60.1° F. or 15.6° C. 9 days=65.5° F. or 18.6° C. 16 days=59.8° F. or 15.4° C. 10 days=64.0° F. or 17.8° C. THE CODLING MOTH IN MICHIGAN. 45 The eggs for these experiments were kept in the outdoor rearing shelter, subjected to the normal temperature. It should be remembered that throughout these tests the tem- perature has been fluctuating and that the separate obsevations can be only approximately exact and we have therefore obtained a great latitude of variation in degrees of temperature for the respective days. The extent of this variation is shown in Tables XLVI and LX in the maximum and minimum records. Variation in the time of incuba- tion should not entirely be ascribed to inadequate methods of record- = enw ay = i (SSeS oj == = (Sea == Sse ees = ae == 2a2= === Spates a SS=222) = a +——} =e ee == = ats {4 —-—+ ees) CSS SSS eee eee CC == =< 5 == ° 20 | = Sa Eee =| ea: ie lf (=== we) ° : 75° eo 30° Py; Jer7peralure LF.° ofi7rst brood, eS econd brood of eggs Fig. 15.—Curve showing relation of the temperature to the time of incubation of first-brood and second- brood eggs of the codling moth at Douglas, Mich.,1911. (From Tables XLItland LVII.) (Original.) ing observations but also to natural influences other than tempera- ture. It has been constantly found that eggs deposited at the same time have varied several days in hatching. Moisture conditions no doubt also have a bearing upon the length of incubation. The writer has found that eggs do not hatch readily during the prevalence of extremely dry weather. The ‘critical’? temperature for the eggs of the codling moth can not be determined from the present data. It is theretore not possible to establish the degrees of accumulated effective temperature required for hatching under any given degrees of temperature. 46 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. FIRST-BROOD OF LARVA. Time of hatching—The earliest newly hatched larve appeared in the field about June 7, eggs being deposited on May 28 and the first larva from the band records being collected June 27. The greatest number of larve hatched between June 17 andJuly 7. Afewisolated larvee hatched as late as July 20. ; Length of feeding period of transforming larve.—The feeding period for the transforming larve of the first brood was determined from 70 individuals, as given in Table LV. The average length of feeding was 21.25 days, the maximum 29 days, and the minimum 15 days. These results show a shortening of the feeding period as compared with the records for 1910, which must have been due to the excep- tionally warm season of 1911. TaBLE XLVII.—Length of feeding period of wintering larvx of the first brood, Douglas, Mich., 1911. ; ) Mot Date of— | ] Non Date of— | | Nox Date of— of of | of reel I) AS a DE 5|| Days ob | feed- || > | feed- || OP- feed- set- | Hatch- | Leaving | ing. ae Hatch- | Leaving | ing. = Hatch- | Leaving | ing. ox ing. | the fruit. ton: ing. the fruit. tian ing. the fruit. | eager Sa) ears SS 1 | June 7| July 11| 34 10} June 22) July 12) 20 19 | June 26 | July 24] 28 2|June 13| July 6| 23 11 | June 23 | July 13| 20 F073 eeadoue es Tila | Se SHUN or hyaek aa wo 12 | June 24| July 12! 18 Di eee CON |e Oscar 32 Ag ead Osnone July 14; 2 IBN SeOOsosse July 15 21 22 dorss: Aug. 3] 38 5| June 18| July 12| 24 14 June 26} July 14 18 23 | June 27 | July 24] 27 6 Oeias Juliye2oel eos 15 doe July 18 22 24 does July 30} 33 7 do Ores =e S| 16 dose July 19 23 25 do Onna 33 8 | June 19| July 19| 30 17 dose July 20 24 26 do JUDE | aa 9} June 20} July 17 7 Sead Oueeee Jiumliye2Se Peed 27 do d0=s222 41 IA VOTACC iz Se hae etc A estes Se One Sie ascreiates Diese Se Sia Po Ste oc 28.2 Mla aT IM oe os Ars ses Sw re a ae pm pe eee eee et eee 41 JWT DY 605 Soe co tees sor aceeec sa ce = cass eae bossa coesess seacssuesgoscees=s Pe ae oie oe 18 Length of feeding period of wintering larve.—On comparing records of the feeding period of the wintering larve with those of the trans- forming larvee it will be noted that there is a marked difference, in that the wintering larve fed for a much longer period of time. The aver- age for the wintering larvee is 28.2 days, the maximum 41 days, and the minimum 18 days (see Table XLVII) and for the transforming larvee the average is 21.25 days, the maximum 29 days, and the minimum 15 days (Table LV). This difference of habit of the two sets of larvee was also observed during 1910 and has been referred to in connection with the studies for that year. About one-half of the first-brood larve recorded in Table LV were reared in bagged fruit on the trees, and the other half in fruit in cages. THE CODLING MOTH IN MICHIGAN. 47 Within a week of the maturity of the larve the bagged fruit was removed from the trees and placed in cages. The average length of feeding of larve in bagged fruit was 20.96 days against 21.43 days for those reared in fruit in the cages, being a difference of less than half a day. Time of maturity of larve—From the band records the time of maturity and the relative abundance of full-grown larve are deter- mined for field conditions. The Douglas band records (fig. 18) have been taken as typical and represent also the surrounding sections of the station. The first larvee were collected June 25 and subsequently in abundance throughout the season. It is estimated that the last larvee of the first brood appeared September 10.! Percentage of transforming and wintering larve.—Table LXVULI shows that 40 per cent of the first-brood larvee transformed and 60 per cent wintered as larve. The observations are from five sepa- rate band records. Larval life in the cocoon.—The larval life in the cocoon is here broadly considered to be the time necessary for the making of the cocoons, and is recorded from the time the larve leave the fruit to the time of pupation. More closely considered, this period actually includes the time the larva searches for its hiding place and the pre- pupal stage, when the larva remains inactive and undergoes struc- tural changes previous to transformation. The wintering larve of the first brood are not included here, as these remain in the larval stage until the following spring. The results of 132 observations (Table XLVIIT) show a variation of 2 to 18 days and an average of 7.2 days. The data for the extremely short periods of making of cocoons are somewhat misleading in that certain larve in the act of making the cocoons have been disturbed by others and have then abandoned the first cocoon and made a new one. The records of Table XLVIII in such instances only show the time for the making of the last cocoon. The prolonged period of time as found in some cases is probably due to a diseased condition of these larvee. 1 For methods of determining the time of appearance of the last larve of the first brood and the first larvee of the second brood see page 15. 48 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaBLeE XLVIII.—Length of the pupal stage of the summer brood, Douglas, Mich., 1911. of obser- | No. OOONTO Or ww DD rearing cages extended from July 6 to August 8. vation. Date of— - Emer- Leaving | Pupa- SiGe: é : g fruit. tion. IGE July 6) July 91] July 22 SOM cee) divliy 10.) divlhys Ze 2d O=see 2 RO eee July 23 dos eGOre Oss ..do. SHO 2a July 25 ..do. eed O= 5222 July 23 2. July 26 ..do. ES doves: July 25 doe Se Ose July 24 rd O aes ALO wESs ZAC O3z22 20 025-02 10022204 July 23 20 (se SAG Oeeede S2d Oe Ad Ovetce Out se doses Ey sae Be eee July 26 PAO OLaeae dose S023 == EdOs=ee SOME Save July 28 EGO seee ed Ouse. July 27 ed Olaeee ely sila | aes doses et dO: 2-3: edosate- FACO SB" Ad OEe see 220M sece July 26 PE dO mee BECO = aces Aug. 1 0 -222= BOO Seace July 27 Pa do2 8s ee (6 pee July 26 = dOsscae se0 eee C0) Se te ad Ove225 Ed Oe eae July 27 B= Oe =a topes BCOs=a a4 pa GOu oes SAO OV Oo July 28 5a (oma SAGO Re July 26 PE Omereee July 12| July 28 OOS see July 14 | July 27 dOs tee doy sie: July 30 S3dotee July 1 |) Ans. 4: July 9] Juiy 14| July 30 BO Saaee Ba erese July 29 Etdore- SAO ast July 31 Oss se Ea Os-e2= July 29 Ee Ona Bea ase July 30 = JC eaoee ad O2s=—= July 29 HO OE Aas doses ECO MEEAS 2 dOsas—e AGO ae July 30 OOS July 15 | July 31 Ped Ger SSO Ghee ce ECO tae SAGO EBESS dO sp— Adot = dose urlyaw 7s eA See dimlive “12 |e aC @cese July 31 Osea July 18 | Aug. 1 EAdote 2 2d Oe Aug. 2 seOl Sane = RdOse =~ 2d0= = 2c0 Ge sase do BAG Oe eeee edges: BOO aan Aug. 3 eed SECO OB AESe 20 5 32 [ome COseee: wd Oe Aug. 4 260 Cxeace July 19; Aug. 2 eR Ne EE Rosie do. Aug. 3 July ae ee edons- = sdOEssee PaO nea mad oleae FEO OG Pee Fa Ouse = 22002 Ew Oss=¢ an aa 1G (a gee Aug. 4 leah gs? July 20| Aug. 3 Juliyent2 see douse: Aug. 4 Se Cae ee (ees doz: Sry een ote == do! i uly 25 |Se dose Aug. 5 re ee ee July 21} Aug. 4 juhyae tulsa dosses- Aug. 5 See ees Adom =a! July 12| July 23] Aug. 5 Mee ee eaten dois: Days— Making of cocoon. = SID DD D.D HD TD C100 D DD OVOvV Ot Ot OF C1 Or OV Ht OO CO GD OV OFF Or OT OV OP OL OV OV OT OT He He He He He He He He He He He He He He He He CO % Date of— o§ = 5 ° S| Leaving | Pupa- ° fruit. tion Z O97 ete eee July 23 Oo ehitkys 4S een dose= (A Ne eo gt dGs =e 72 | July 14] Aug. 1 (Ee Hee aCe ene ee doles 74} July 15 | July 21 75 | July 16} July 24 f(a eae eee ek dose ti | sully V7) Saly 21 7 ER O22 2s | dO ee (Mie ee WSao S= July 23 80° |= 00.3210 Sih rend onrase Ra) (0 ee VAM | me One e July 24 GB llsec@@ecese July 25 84 edo sse2- July 26 Son |-=adosses- July 27 SOuWenedose=ee July 28 Sila dos BO One te 88 | July 18 | July 24 895) 5-2 00222442 Olas 90a doses July 25 OIG se dousaes Bes (oe ODN le dorasse S(0 Oya 9352220 0n snes Hrd Ose eee O45 ke ) Te ole corte elle ole sory Wiia lila) — 2) cf — Wok bo — Time of pupation.—The time of pupation as represented in figure 20 has been determined on the basis that the time and rate of emer- gence of the moths must be in close relation and in direct proportion to the time and rate of pupation. Observations on pupation in the In the field, how- THE CODLING MOTH IN MICHIGAN. 49 ever, the pupation period was longer. From the records of emer- gence of moths we find that the earliest pupz: must have appeared about June 30 and the last pupz about August 24. Length of pupal stage.—In the course of rearing work two separate tests on the length of the pupal stage have been made. One of these (Tables XLVIIT and XLIX) includes primarily observations on the pupal stage; the other (Table LV) contains observations on the life cycle of the insect. The results of Table XLVIII, including 132 insects, show that the period varied from 6 to 21 days, with an aver- age of 14 days. The results from the life cycle series (Tables LV and LVI), covering 75 observations, showed a variation of 11 to 24 days, and an average of 15.18 days. TaBLE XLIX.—Length of pupal stage of the summer brood, Douglas, Mich., 1911; summary of Table XL VIII. Number| Days Number | Days of |} Number| Days | Number] Days of of obser-| making || of obser- | pupal of obser- | making | of obser- | pupal vations. | cocoon. || vations. | period. || vations. | cocoon. | vations. | period. 1 3 13 9 17 14 2 16 18 4 1 6 28 15 2 18 21 5 4 10 5 10 24 16 17 6 3 11 8 11 - 17 10 7 25 12 1 12 3 18 23 8 21 13 1 13 1 21 Taste L.—Time of emergence of moths of the summer brood from band records, Douglas, Mich., 1911. | | | Band records. Band records. cs) = oo S S| ° P| cS) Date of ‘ 3 = ‘= Date of : ; g = emer- EK H Ss emer- = u gence A a = = = gence 4 Z = <= a Perey ue oR | plo es, We ot ce bee 21s 5 5° 5 3S Be lpea 5 Bo) al ub Ss A = a Z faa) a A 4 Ba Z aa a Sully = Ss ae ee eee ose 2 3 5 || Aug. 13 3 10 Greases 3 22 Tyan Oe eee a= eran erainiw's aero | vets inc 4 4}; Aug. 14 6 13 19 3 12 53 July 10 1 2 + 3 21 33 || Aug. 15 1 5 iLO) | Pern 1 17 July 11 1 2 8 5 16 S2e PAU oareL On| eee ae 8 1 1 16 Sadly. e122 ee 3 Aa eee aco T NeNuesoty lone: 8 6 1 3 18 July 13 2 2 16 1 lyf 38 || Aug. 18 1 12 | UE eee ae | Pe 22 Julya 14 eee 2 ) IS Sener 19 SON Ati se) 19) |e eeee 5 Spleen oe | 8 Tuly> |S. 22 2 2 al Neen 9 fi | eet oO) | ease | ee ree Bole eee tel 5 duly ah sess 1 oe 10 13 || Aug. 21 3 8 2 4 4 21 dilye hyale t= 1 2H ieee ll 15 || Aug. 22 2 5 | 5 1 2 | 15 Tulye. AGEs ees 4 3 1 10 Sie ANT One 2 eee 3 2 eee 1 6 PU Lye OR ee eae 2 iy eee 11 18 || Aug. 24 2 1 Sa eee 1 7 lye AOE oss 2 1 1 8 12 Ane. 25 es 522 4 Dee ee lee 6 oly is as Seee 1 Piles gee 10 13 || Aug. 26 2 3 | 2 Paseo 8 July 22 1 1 1 1 11 TSAI Se 2 ieee 2 1 1 a ee es a a Siulivees2os| mae 6 2 2 8 18 || Aug. 28 1 2 PA eee | ete 5 July 24 ]....-- 2 2 1 8 13s) PANE ZO) eee 2 PA exe Puts es eae act 4 ital vee 25 l= ae 2 2 2 10 LG E PAU Ss SOME a= 1 lhe |es Sei 1 3 July 26 |-..---- OS ae mae 3 9 21 || Aug. 31 11g ame ae 1 2 Eee 5 etl ys 270i sc Gulsaes xe Dain 37 15 || Sept. 1 2 i ete ee Pe 03 3 July 28 1 4 Dalene 7 14 || Sept. 2 1 2 1 4 9 sail 29 sores 4 2 2 11 19 || Sept. 3 2 GE tens ee Pee eoncle | 3 6 July 30 2 5 2 1 10 20) \ieseph: 4) )\S2225- Dl eRe eaters 1 3 July 31 4 4 4 TAS a) aralSept ses) lps css 1 | Dhaai 1 5 Ang. ll 1 2 13 4 19 39i| | ROCDENwOR ERE tec aacn- 2 2 ifs oops ames eee 1 SAU iste me Dil en 5 1G ene 4 GW Se Dusen alee 1 it} 1 eee 3 Aug. 3 2 4 15 2 12 SY Se lis, tedlecoooe 1 De oe eee 2 Ae eA | 4 1D exe 13 8) Il SEs =) iccaoae 13 ee UR Se A aoe il Aug. 5 10 10 17 2 13 GEA TAS rey oy ry DKON eS Si tee a apse eaerea eo N tee 1 1 Aug. 6 8 4 12 2 14 AGH eSep te ells hsaaesleessa-- 18) Pe ees) elses ci 1 Anes = 7 12 15 35 11 17 SOHIESeptsdGat = oe eeme | Sees Paesed 1 1 Aug. 8 + 14 16 7 19 CON SOE AVC Seneina pocatce basaaeolsesces | 1 1 Aug. 9 6 19 20 2 13 FO) dit Seo US essoec ssessaslecasass leona. | sa 1 Aug. 10 5 22 23 5 12 67 —= | gare Aug. 11 1 9 20 3 6 39 Total - 91 287 | 372 89 | 440} 1,279 Aug. 12 3 13 TiN Sess 7 30 50 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. FIRST BROOD OF MOTHS OR SUMMER MOTHS. Time of emergence-—The records for emergence of summer moths are given in Table L, covering 1,279 observations from five separate band records. The codling-moth larve from the band records at Benton Harbor, New Richmond, Douglas, Lake Shore, and Pent- water were all sent to the station at Douglas, and the observations on the date of issue of the moths were all made there. The curve of figure 16 represents the total emergence of moths and is based upon the records of Table L. It will be noted that there existed a striking similarity in the rate of emergence and that the time of emergence ° 'o & ®, @ o ao & 7 We Fo Ry _ ie} a o 9," co Lo) ay 2, or oF on i 2. > °o =<) oO, io a Ga S - oo Number of Moths, co me FB prayuedye 4y-ounje. sdwat, Apep ebeueay nD oO —~ ETAT PE [os \R, So i > or Bil s4aniz 20.23 2b.2% 1) 4) tO NS 16: (22925 26 Siesta ais July August September Fic. 16.—Emergence curve of moths of the summer brood in 1911, at Douglas, Mich. (Original. ) was practically the same for the different band records. This may be due to the peculiar climatic conditions of 1911, when the spring opened up uniformly over the entire fruit belt—a rather unusual occurrence. It may also be that during the middle of the summer the seasonal conditions became equalized over the different sections, and produced a corresponding equalizing tendency upon the develop- ment of the codling moth. The emergence records for the summer moths are remarkablo both in respect to time and rate of appearance of the moths. The earliest moths issued July 8, which emergence was 21 days earlier then that of the more normal season of 1910. During the early part of the emergence period, from July 10 to July 14, moths appeared in abundance. During the later half of July, however, they were less THE CODLING MOTH IN MICHIGAN. 51 numerous, while during the first half of August they were again very abundant, reaching a maximum August 7. During the remain- ing part of the emergence period, which extended to September 18, comparatively few moths appeared. TaBLE LI.—Oviposition of moths of the summer brood in captivity, Douglas, Mich., 1911. | : Date of— Days— Num- Num- ber From ber of time of of moths | Emer- First Last Before Of emer- cage. per | gence of | ovipo- Ovipo- | Ovipo- | Ovipo- |gence to cage. moths. sition. sition. | sition. | sition. |last ovi- posi- tion 1 294 July 10] July 14} July 20 4 7 10 2 24 | July 11 |...do..... July 24 3 11 13 3 10} July 12 }-...do..... Aug. 1 2 19 20 4 29} July 13] July 16.) July 27 3 12 14 5 26 | July 14] July 23) July 24 9 2 10 6 15 | July 15} July 18] July 26 3 9 11 7 10} July 16] July 20] July 28 4 9 12 8 14 | July 20} July 26] July 31 6 6 iB 9 15 | July 21] July 28) Aug. 5 7 9 15 10 16) July, -22).2-do-.-.: July 30 6 3 8 11 PSV eaiulivs 23) |e dOse 2 Aug. 4 5 8 12 12 13 | July 25) July 27 |..-do..... 2 9 10 ° 13 25 | July 26) July 31] Aug. 1 5 2 6 14 11 | July 27 |...do Aug. 2 4 3 6 15 14| July 28] Aug. 1] Aug. 7 4 7 10 16 17 | July 29] July 31) Aug. 14 2 15 16 17 18 | July 30] Aug. 1] Aug. 10 2 10 11 18 36 | July 31 |) Aug. 2] Aug. 18 2 17 18 19 37 | Aug. 1] Aug. 6] Aug. 7 5 2 6 20 LonieAtie< 22) |e Aue. 5) Annie. 9 3 5 ¢ 21 38 | Aug. 3] Aug. 6] Aug. 15 3 10 12 22 OA PAIS 45 Rowse Aug. 16 2 11 12 23 54} Aug. 5] Aug. 7] Aug. 12 2 6 a 24 35 | Aug. 6] Aug. 8] Aug. 13 2 6 7 25 88 | Aug. 7] Aug. 9] Aug. 16 2 8 9 26 55 | Aug. 9 | Aug. 11 | Aug. 17 2 a 8 27 54 | Aug. 10 | Aug. 12 | Aug. 31 2 20 21 28 27 | Aug. 12} Aug. 13; Aug. 23 1 11 11 29 19 | Aug. 13 | Aug. 17 | Aug. 21 4 5 8 30 47 | Aug. 14] Aug. 16] Aug. 25 2 10 st 31 21 | Aug. 16} Aug. 18 | Aug. 28 2 Tt 12 32 1G) Aes 17 ee sdouss. Sept. 3 1 We 17 33 27 | Aug. 18] Aug. 21 | Aug. 28 3 8 10 34 23 | Aug. 21 | Aug. 22 | Sept. 14 1 24 24 35 15 | Aug. 22 | Aug. 25 | Sept. 3 3 10 12 INSTORE el Bs OL SS eis ele arst sa ee a gage 32 9.4 11.6 Maximum........-- Delis ke Seay emer Sr Bee in 9 24 24 SV Aeriea rane rans eee Roe are Ls Iie ean cen gs Burt Roc “il 2 6 Time of oviposition.—Observations on egg deposition by the sum- mer moths. in captivity were made under conditions already described on page 14 for the spring brood. The results as presented in Table LI show that on an average the first eggs were laid 3 days after the time of emergence of the moths and that oviposition extended on an average to 9.4 days. Within the various cages considerable variation will be noted; in one instance the first eggs were obtained the following day after the emergence, in another instance the ninth day; in one cage the last eggs were deposited the sixth day, and in another cage the twenty-fourth day after the time of emergence of the moths. 59 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. On correlating the above observations with the time of emergence of the moths it will be found that the oviposition period extended from about July 11 to September 25. However, very few eggs were laid during September, and not all of these hatched. The great majority of eggs were deposited during August. Taste LII.—Length of life of male and female moths of the first brood; summary of records of 1,019 individual moths. Male. Female. | Male. Female. | Length | Number| Length | Number || Length | Number} Length | Number of life. |ofmoths.| oflife. |ofmoths.|| oflife. |ofmoths.| of life. | of moths. Days. Days. Days. Days. 1 1 1 1 18 6 18 10 2 8 2 5 19 2 19 9 3 16 3 6 20 5 20 10 4 22 4 15 21 2 21 13 5 22 5 24 22 1 We 9 6 42 6 32 23 2 23 7 46 7 27 25 1 24 2 8 48 8 62 26 1 26 4 9 50 9 46 32 1 28 1 10 41 10 5 RE] | ener ee ee ene eee 29 2 11 30 11 2 SN | Die eae Pel eB aA oe 30 1 12 32 2 5 te | Seapets a em Tal 32 1 13 18 13 AQ see Sa ears 33 ij 14 24 14 ES Mig | eee ee tet| JE Te ahaa 37 1 15 12 15 26 || 16 11 16 22 Total. . 496%, |ooas see eer 563 17 12 17 14 TaBLe LIII.—Longevity of male and female moths of the first brood; summary of Table LIT. Observations. male female Days Days IAVOTAGCH. eee See en 9. 57 11.49 IM aoxdim tH 5-2 os ee ee 32 37 Length of life of male and female moths. —A summary of observations from 1,910 individual moths is recorded in Table LII. The condi- tion under which the moths were kept has already been referred to on page 39. As observed for the previous brood, the longevity of the males was shorter than that for the females. On an average the males lived 9.57 days and the females 11.49 days; the maximum length of life for the males was 32 days and for the females 37 days. It is of interest to note that the results obtained by the writer at North East, Pa., in 1909,‘ are almost identical with those given above; the average length of life for the males being 9.79 days and for the females 11.47 days. 1 Bul. 80, Pt. VI, Bur. Ent., U. S. Dept. Agr., p. 91, 1910. THE CODLING MOTH IN MICHIGAN. 53 The females were found to be more numerous than the males, which was 2lso observed in the spring brood of moths. Length of life cycle of the first generation.—in Table LIV are brought together the average results from observations for the separate stages of the first generation. These data show that on an average there elapsed 53.59 days from the time of appearance of eggs of the first brood to the time of appearance of eggs of the second brood. Com- paring these results with those of the complete life-cycle series (Tables LV—LVI), there will be found a difference of results of less than one day. In the life-cycle tests 75 individual insects were under observation from the time of the deposition of the eggs to the time of emergence of the moths that resulted from these eggs. TasLeE LIV.—Summary of results from experiments on the separate stages of the first generation of the codling moth in 1911. Number of days. Life cycle of first generation. Average. | Maximum.| Minimum. IER GED REIN MORE RE Sey weer yt aa ee ee SI ea ts es 7.94 | 10 4 Reed Wis RerOdO blarvrE ease Oe Sa oe Se ee Se | 21.25 | 29 15 RE AE OH COCOONS eer eee ey ee ee eae See 7.2 | 18 3 LeUy re Sa a = Sa Te ee See Se ee ee ee ne Se =. 14.0 21 6 Rie PelOre CaS! CEROSTEION sae ae ae eee Oe ee | 3-2 9 1 TAGE 8 oe Be Oia ae Se eee NR a ee | 53.59 | 87 29 TaBLe LY.—Life cycle of the first generation of the codling moth, as observed by rearing at Douglas, Mich., in 1911. Date of— Days for— Aue lof ob- | serva| Egg | patch | Latva | papa | Emer-_| patch-| Feea- Making] p, ay Total tion.| deposi- | “jn> leaving As | REED Te ae ea | lift tion. e- | the fruit. = 9) anoth: * | S = |ecocoon. | Ee | cycle = ee a See 1| June 1} June 10} July 4j| July 9} July 22) 9 24 5 13 | 51 Pics een) Cs ee dor = 22). 022522 halve tis po ete 9 24 ales ee ee ede aby 06: -= 4-002... -|---do>.2-- July 27 | 9 24 | 7 16 56 A tme sf Jone tt |. -do..... bly ES) Pe te ee 8 23 AND: eon 5|June 5| June 13| July 8| July 26| Aug. 8| 8 25 18 13 64 Gedo) =: ies ae | July 9] July 14| July 31| 8 26 | 5 17 56 17| June 6| June 15| July 6| July 9} July 23 9 | 21 3 14 AT ei Be ga ler Gi July §| July 11| July 26 9 23 3 15 50 Oe do =a =e Oo =" Si (tees H002s2=2 doses. 9 23 3 15 50 fDi e-—do2"s=-| exdov= =: ado2 22 Tdour- ado= = 9 23 | 3 15 50 ©1t-lo de.s..- mrdotse |. donc July 18] Aug. 3 9 23 | 10 16 58 15 DS EaaG Tee 20 July 9)| July 16} Aug. 1 9 24 7 16 56 ES Ee edor-25- =a Gee eee stecteccea 2July 31 | ene ai | a | a 55 | 114 |...do..... be = Oe == 2 fives Se eee pate coe 2July 25 3 t)| eeae Sed ae ee ee en eee 49 | ist saves pone Is | July 8 | Joly t1).-----..2 10 20 5 Were ete 4 ele ee LES (a AG G ae BOOSTS = July 12| July 24} Aug. 7 10 24 12 14 60 117 | June 9 |}---do...-- July 8| July 2} July 31 9 20 4 19 52 Eisife==do-=- <= i= -“d@--- == July 9/ July 13 | July 30 9 | 21 4 17 51 219" )2 5c dds2—= 1 2. dO5 25. dorx2-: | July 18} Aug. 3 9 | 21 9 16 By) E20) | == 200: 232" done July 12 | July 14} July 31 9 24 2 17 52 21 | June 10 | June 19 | July- 8 | July 13| July 29 9 19 | 5 16 49 Beat dO = 25 dot oly: Wulkolye otis: 9 24 | SOU seal eee Pee eOrsas|-- -dO_=— Airtel 2 a) ees Ce epee 9 25 | Lal econ ee Heese 27. 35 ee 3 (ee HAG eee Ose: July 21} Aug. 5 9 25 7 15 56 JE. | EG fy eed a Ce eee Tine, Cay | |e Li hee) ea ade 9 26 7 i eens nee {= 26 | June 11! June 20! July 61 July 10) July 23 9| -: 16} 4 13 42 | 1 Bagged fruit; average feeding, 20.9 days. 2 Pupated in fruit; average feeding, 21.4 days. 54 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaBLE LV.—Life cycle of the first generation of the codling moth, as observed by rearing at Douglas, Mich., in 1911—Continued. Date of— Days for— No. i of ob- 5 | 7% 5 serva- gg 2 arva _ |. Emer- E Makin Total tion. | deposi- ee leaving vps gence of Hae roe of ;: Vupal life tion. a | the fruit. < moth. = 8- |eocoon. | Pete. cycle. 27 | June 11 | June 20| July 7| July 2].......... 9 17 5 |eseeknn eee 28 O82 OOS aee O=- Oe July 29 9 17 5 17 48 29 do=e2= Sad OC ase July 91] July 13 | Juiy 30 9 19 4 17 49 30 Gree ead Ose2es July 13] July 18 | Aug. 4 9 23 5 17 54 31 dos=n = ..do Ons. a= July 20| Aug. 5 9 23 u 16 55 132 doses. ee doceece July 7| July 12] July 28 9 17 & 16 47 133 doz Eos! os July 9) July 13 | July 31 9 19 4 18 50 134 Gosses- do-.. dose July 12} July 28 9 19 3 16 47 135 Goren noses July 13} July 19} Aug. 4 9 23 6 16 54 36 | June 12 | June 21} July 6] July 9} July 22 9 15 3 13 40 37 dos ~AOsesee | July 8] July 14) July 31 9 17 6 17 49 38 Goxess AO Ose ae July 10 | July 16) Aug. 1 9 19 6 16 50 39 doses Xdo tee = =O O ese se July 15} July 31 9 19 5 16 49 40 dome dose SOW sa-6< July 16] Aug. 2 9 19 6 17 51 41 dom: doze: Heian eae Oke Aug. 9 9 20 5 24 58 42 dos douss: ed Omeeee July 15 | July 31 9 20 4 16 49 1 43 does Gomes: July 9 |--.do- doers 9 18 6 16 49 144 domsae does dle US eee ccoase Aug. 8 9 7A Peers teeta | pod 7 eeabnas 57 1 45 dows Gon eaie ee Sea | ee eee 2July 31 eee let ibet | Lad ae oe 49 46 | June 13 | June 22| July 11]! July 20} Aug. 4 9 19 9 15 52 47 Oleence GOrss- SEO July 18 dose 9 19 7 17 52 48 dos dO. -=- Tuhiypet2 eee domeas Aug. 3 9 20 6 16 51 49 dos douse ~Oscaeq July 21} Aug. 5 9 20 9 15 53 150 | June 14 dostss: July 10] July 15] July 31 8 18 5 16 47 151 does | | Date of— Duration of— No.of | Num- gee obser- | ber of _ | Appear- 3 vation.| eggs. | Egg dep- pee ance of Hatch- | Red | Black | Incu- ee | osition. | jog ring. black ing. ring. | spot. | bation. Ure: spot. Days. | Days. | Days. a ae 1 18 | July 14] July 18] July 20] July 22 4 6 8} 66.96 2 23 | July 15] July 19] July. 21 | July 23 4 6 8 66. 83 3 35 | July 17] July 21 | July 23 | July 24 4 6 7} 66.00 4 59 | July 18] July 23] July 25] July 28 5 7 10 64. 60 5 G7 li Tualye 19) | Ouliyas24 | lyons edossas 5 8 | 9] 64.18 6 Ne eC Ge cllos Os ss sIice-CWsce sl Uwlhy 29 5 8) 10 64. 67 7 64 | July 20] July 26] July 28 |._.do.... 6 8 | 9 64. 35 8 Bo scC Oss osllbecOWOsso\|eo-CWs5e0)| Uulhy so) 6 8 | 10} 64.73 9 5 | July 22 | July 27 | July 29} July 31 5 7 9 65. 41 10 8 |...do “CO s55 c\icocClses ol] ANE Il 5 7 10 66. 47 > hh 27 | July 23 | July 28 | July 30 | July 31 5 7 8 65. 09 12 WS NecCOscc cl-ccOMsosall dik, sil |) Ames a 5 8 9 66. 30 13 NG |) dhebhye GAS) aolbyy 28) CMs a clloec6Oscue 5 U- 8 66. 63 14 17 | July 26} July 31} Aug. 1 |] Aug. 2 5 6 7 69. 20 15 WY |) MN 2 sco lWag Sa |lecoOlseSclleceO Moa 4 5 | 6 70. 33 16 4 |_..do EEO es aes dose INI, 83 4 5 7 69. 76 17 12 | July 28 | July 30} Aug. 2 CMsoc6 2 5 6 70.7 18 4 ) Sp OO aes|aes doze Aug. 4 2 5 7 70. 08 19 14 | July 29 | Aug. 2] Aug. 3 Ouse 4 5 6 70. 23 20 3 do san aco cleceOlsGocl) dw. 4 5 7 70. 22 21 WH) sulky SO esclOooocl| Aue, 4! les eGsase 3 5 § 70. 55 22 12 do aCOEe eS Eee do.. Aug. 6 3 5 a 71.00 23 O5u | uly; ols) |Sesdosees | eAtiey nS domeere 2 5 6 70. 5 24 30 0-02 (Es B55 oloonOMso5 oll, 2 2 5 7 71.07 25 AG | Auge, 10) Aes 3) |—eedoseae GWscec 2 4 6 70. 25 26 22 GWsocolbocCaqoc| AME Gl) Auk 2 5 7 71. 22 27 Py | UN || NE, 9 G2) INEST) cae l@sccc 2 5 G6 71.29 28 4 CWsseclsec do.. =s0Ose Aug. 9 2 5 7 71.01 29 40 | Aug. 3| Aug. 5] Aug. 8 Ones 2 5 6 71.81 30 8 0) IND © leesOW5< Aug. 10 3 5 7 71. 74 31 30 | Aug. 4 |...do Aug. 91} Aug. 11 2 5 7 72. 61 32 1A ATIC 75) PAIS 8) | PAoN ON aad osneer 3 5 6 73. O01 33 | Saaao IMDES Tf Ness 5a5)) Jus 1 2 5 7 72. 20 34 Tg Aus S6nl Aton = Su PAties oii | aedoes 2 5 6 71.95 35 (GO) eS cCWe Sea) SocOleodalsosOe Ss ca|) VNTOYS, 1183 2 5 7 71.00 36 188] Aes 4) S-2dox se Anos 12) Aries 4 1 5 7 69. 97 37 18 @MSGos|iese doz...) Ayo: 13: | Auge 15 1 6 8 70. 39 38 309) | eAtue. (8))|/eAtion Hy | Aico s4s |B edosnc- 3 6 7 66. 59 39 3} ke oGWoouc CMs scolloneGie Aug. 16 3 6 8 69. 47 40 3) Antes 9) | PAuon h20eaadoz Aug. 15 3 5 6 69. 47 41 99) |ba2 done 5 | SasdOne saa do. Aug. 16 3 5 7 69. 49 42 13 doszeee do....} Aug. 15 | Aug. 17 3 6 8 69. 96 43 298 | Aug. 10 | Aug. 13 |.--do-- te) ‘ 3 5 7 69. 86 44 4 CWss6 cllascOMscecllecc dons Aug. 18 3 5 8 69.99 45 310 | Aug. 11 EdOn soe) Aves 16) | Anuigs 7 2 5 6 69. 33 46 130 do Aug. 14 |...do.. Aug. 18 3 5 7 69. 56 47 37 do Sco Aug. 17 | Aug. 19 3 6 8 69.15 48 128 | Aue 125) Anion Wo | Soedozes =| eaie.a'S 3 5 6 69. 92 49 Sie [pee G Ona Rae GO ss sales Coe cl! wey Ne 3 5 7 69. 40 50 130 | Aug. 13 | Aug. 16 | Aug. 18 | Aug. 20 3 6 7 68. 65 51 WO? h.-6Wsh5 cllencOWMsoualisce Ones) Auer 3 6 8 67. 68 52 87 | Aug. 14} Aug. 17 | Aug. 19 do 3 5 7 67.77 53 pac @a5a5|sacdscqn|| AN, Ai) |) Jule, 22: 3 6 8 67.86 BN SG) bes, UGS Nee Casco al) Nw AA loeeClOo sce 2 6 7 67. 07 55 GG les eGObaes bokseeoc| bee does. |) Aued 23 2 6 8 | 66.85 56 8 |...do Roe ae ieee!) Aus Oe 2 6 9| 66.08 57 Seldon sales do....| Aug. 22 | Aug. 25 2 7 10 | 65.40 58 37 | Aug. 16 | Aug. 19} Aug. 23 | Aug. 24 3 0 8 | (65.63 59 N2/ ou One 51552 do....| Aug. 25 3 ul 9| 66.04 60 27 |...do....| Aug. 20 | Aug. 24 | Aug. 26 4 8 10 | 64.23 61 SF leceOs ec aleacO Won salleacCa cu al! ANU 27 a 8 Wl 64.16 62 21 | Aug. 17} Aug. 19 |...do....| Aug. 26 2 7 9 63. 22 63 39 |...do....] Aug. 20 | Aug. 25 | Aug. 27 3 8 10 63.24 64 AD) || SsC Osco clisacCOsod clless do....| Aug. 28 3 8 11 63. 72 65 PANG |) Aires AS | eecC@asoa|| AWS AD lessCs55- 2 8 10 62.99 66 1S |ecOWsocelleec@Ms oe cl! AWE AY || Awe, ZY 2 9 11 62.97 67 26 | Aug. 19 | Aug. 21 | Aug. 28 | Aug. 30 2 9 11 62. 00 68 AS Eee doe Js 50.a\loec COsa5 al) bles Sil 2 9 12 61. 69 69 119 | Aug. 21 | Aug. 23} Aug. 30} Sept. 1 2 9 ii 61. 71 70 28 IOs 5 slloce Goteeslaee do Sept. 2 2 9 12 62. 36 71 32 | Aug. 22 | Aug. 25 !...do.. Sept. 1 3 8 10 61.038 | — ne ———- — 57 Taste LVII.—Length of incubation of the second brood of eggs, and average tempera- ture during incubation, Douglas, Mich., 1911—Continued. THE CODLING MOTH IN MICHIGAN, Date of— | Duration of— No. of | Num- ee obser- | ber of Appear- vation.| eggs. |Egg dep- dae ance of Hatch- Red | Black | Incu- pee osition. red ring eae ing. ring spot. | bation. ; Days. | Days. | Days. oie 72 80 | Aug. 22 | Aug. 25 | Aug. 30 | Sept. 2 3 8 1 61.81 73 50 | Aug. 24 | Aug. 26 | Sept. 2| Sept. 4 2 9 11 61.96 74 Sela GOSS |= OSes 55200 -455| Septaeo 2 9 12 62. 23 75 21 | Aug. 26 | Aug. 30 dots |a22dos= 4 7 10 62.95 76 46 | Aug. 27 | Aug. 31 | Sept. 3 do.. 4 7 9 62. 90 77 Go fe=2d0. = sa)2a2d0n5= 5/5400" --]| epts 6 4 7 10 63.17 78 26 | Aug. 28 |...do..--| Sept. 5 |...do.. 3 8 9] 62.59 79 8) Pe -doss. se =edo. s-=|252d0-- Sept. 7 3 8 10 62.41 80 12 |_..do...-| Sept. 1 | Sept. 6 | Sept. 8 4 9 11 62.39 81 Se|2=sdo.= 2s15"-dor. mS GOEr Sept. 9 4 9 12 62. 84 82 3) | paAue. 30) sept. 20) sept. 8a dol. - 3 9 10 3. 58 83 Gi | Caxe ao clesc sl ee =2d0x Sept. 10 3 9 11 63. 27 84 6 | Aug. 31 | Sept. 3] Sept. 9 |_..do..-. 3 9 10 63. 77 85 Ou | 2asdose =2|=--005=5-|---G0s5—4s|7 pepe. LL 3 9 11 63. 60 86 10 | Sept. 2] Sept. 6 | Sept. 12 | Sept. 15 4 10 13 62.14 7 40 | Sept. 8 | Sept. 11 | Sept. 16 | Sept. 18 3 8 10 62. 46 8§ FAUT ee aE Cpe beatae Sept. 19 3 8 11 62. 85 89 5 | Sept. 9 | Sept. 12 | Sept. 17 .do. 3 8 10 62. 34 90 3 |.--do..--.}.-.do..--| Sept. 18 | Sept. 20 3 9 11 62.06 91 File -G0ss24)2--d05.5-|52-00- = 25! (Septs 25 3 9 16 61.09 92 1 | Sept. 10 | Sept. 13 | Sept. 19 | Sept. 21 3 9 11 61. 86 93 PAN AAC (a yereees| ee do===-|2--d02 Sept. 22 3 9 | 12 61.39 94 ib scales .-do..-.| Sept. 20 | Sept. 24 3 10 | 14 61.09 95 29 | Sept. 11 | Sept. 15 |._..do-. Sept. 22 4 9 11 61. 35 96 GR ed One andes =aeG0-e |) septa 2a 4 9 12} 60.92 97 1 |...do....| Sept. 16 | Sept. 21 | Sept. 24 5 10 | 13 | 61.03 98 ik does. 313. d05= Sept. 22 | Sept. 25 5 11 14}; 61.11 99 3 | Sept. 12° |222do-- - -do. Sept. 24 4 10 By |) GOR zal 100 gL ees (ae es ees dose \es-d0s- Sept. 25 4 10 13 | 60.81 101 19 | Sept. 13 | Sept. 17 -do...-.| Sept. 24 4 9 LPO 102 GE aa doe oe hee do. . ..do Sept. 25 4 9 | 12; 61.27 103 7 al eset G Loy sete ee do. Sept. 23 | Sept. 26 4 10 13 60. 93 104 gi eae (ees ee do. . -dos== =) Sept. 27 4 10 14 60. 43 105 Hel doe doses -do....| Sept. 28 4 10 | 15 60. 47 106 5 | Sept. 14 |...do...-.] Sept. 22 | Sept. 24 3 8 10} 61.68 107 Ae dor soaps doe Sept. 23 | Sept. 28 3 9 14| 60.76 108 7 | Sept. 17 | Sept. 25 | Sept. 27 | Sept. 29 | 8 10 | 12 59. 60 109 11 [priest 0 CO See SdoL=e | Obi a 8 10 | 14 58. 55 110 Dale Ad Oa m0 sere S| MASONS sl OTC | iG 8 10 | 16 57.80 TasBLe LVIII.—Length of incubation of second-brood eggs laid in rearing cages, Douglas, Mich., 1911; summary of Table L VII. Appearance of red | Appearanceofblack| Total incubation ring. spot. period. = Number | +; Number | »,; Number Bumper of obser- Nuae of obser- Noumea of obser- ol days. | vations. YS: | vations. YS: | vations. 1: 2 4 1 6 13 2 27 5 30 7 22 3 41 6 15 8 13 4 24 7 12 9 9 5 11 8 18 10 17 6 2 9 22 11 15 8 3 10 11 12 9 Sp eee sere ae eee 11 1 13 4 SP ene Unease een eee ee arene renee 14 5 5 oi oie es eee | ae eae exes: el vee |S ae a ge 15 1 15 2 58 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaBLE LIX.—Length of incubation of second-brood eggs laid in rearing cages, Douglas, Mich., 1911; summary of Tables LVII and LVIII. | Number of days— Observations. For appear- |For appear- ORnCEe ance ofred| ance of pation ring. black spot. ; AV CLAS Oto: < 8 | July 28] Aug. 19 22 00 |'5-s@Wvenae Sept. 18 S4 |" 144°\-= 2do--=-- Sept. 26 | 36 Oo Rex dOneeee SAGO Ae lena TCE KG KO eee sept. 199} 935 || 145 |--2do: ee COS ae 36 103) S2adosee== ATs. 20! |" 23 TS. oealOen se | Sept. 26 42 WA es OO} coer OCH Th rar: 1H) |sseCl@secce Aug. 21 24 19) |-=-d02----| Sept. 28 AAG || eel Aes dose. | Oct. 3 | 43 1D} |eseCl@esase a6\Qbece- 24 0) iccaG@sccse dou: 44 HAST eed Olena | Oct. 363) 5846 1B} 4 cee sence dose. 24 81 |._:do...._| Sept. 29 | 45 149-|...do.....| Nov. 13 | 84 TAS ed Oeseee Aug. 22 25 82 | Aug. 16 | Sept. 12 27 150 | Aug. 22 | Sept. 29 | 38 5 | ae Osean Aug. 26 29 BB} [cals ose Sept. 14 29 15 1G SesGouee leaeClOsecoe 38 Gh Sead O=== Aug. 27 30 845 Saad Olea BOK See 29 1b 5 Ol aose oacGQueeee 38 fl ees 88s Aug. 28 31 SI NeooGK bones Sept. 17 32 1535) end Osea ROC 7a ee 4G ASE Reed Osee=- sed Osesee 31 SG ecaCkOeoose Bd Oeeee 32 1S ee Oseeee | Oct. 8 |) "47 1G) |e se@Oscoee Aug. 29 32 BY eac@@escac [Ors 32 1 De|aeeGOssse= OCS 4s) 53 PAD eee GKOe ose Sept. 1 35 SSiieed Omens Sept. 24 39 1565 onseee MOCtanIGrie55 Mil |PesCOrsaae Sept. 2 36 SO Se KOO Shee Sept. 26 41 lSy/ Wests 2S} | Ores al || a DPN coOOasne aGOSe ses 36 SON aed ores Oct. 26 71 158y 2220 02s s- | Oct. 3 41 oe | Re OSS ee Sept. 4 38 91 | Aug. 17 | Sept. 8 22 PS On Eead one Oct. 6] 44 24 | July 29) Aug. 21 23 COR eas Ose Sept. 15 29 16OR Es dotes | aedosene 44 5 oO GaSe Salome Se 23 OSE end. Oleees Sept. 17 31 TGs eadoressp Octs 16) 54 26g een Osmo Sdorey-= 23 OEE ad Ose do 31 162 | Aug. 24 | Sept. 29 | 36 2 Wow eOKcese = LO¥sace 23 OH le aeOWObcse Sept. 19 33 OSes Onse= ~-d02222 36 XS Ise Ua acae Aug. 24 26 OF |oca@lecsse Sept. 22 36 G45 ee Goeeee Oct= 137/40 78) Nl eeCO pec oe Vee (LONeae= 26 OP \cocGOhesse WECLO Nee 36 UGS Wes aG sense asCObsece 40 30) ee doles Aug. 29 31 OS ise aC aane EedOs2s= 36 166 | Aug. 25 | Sept. 28 | 34 31} July 31 | Aug. 28 28 SO ead Ose ee Ee dOteeee 36 IOV Woon ose - sa6Osacee 34 52h |eadoueee| exdOvese 28 10D) eecClO,355— Sept. 23 37 IGS || Ol See Oct alee4s 8B) leocOWb cone Aug. 31 31 LOTS) Sea COsseee || aaa Ofeee= 37 INGE) eo OO OCt205 956 Soa Oeeeee Sept. 7 38 L025 Sedo dos 37 170 | Aug. 26 | Sept. 28} 33 35 | Aug. 4] Aug. 28 24 NOB Neel sas Sept. 24 38 Ale enG@ea aoe Oct e6n | 4l 36) == dows Aug. 29 25 104 ae dossa oe | Ree Gosseee 38 UP 15 eG Ox 5 Oyo, 1)" BY Ne ca ecnee Sept. 7 34 105s |S Ones Sept. 26 40 178} eceGlOco5e Octs 165/51 3S leceOOnn ake Sept. 9 36 OS |cecG@sacoe||sce OOsssac 40 (Ae eee Cdosaens Rad OLseae 51 39 | Aug. 6] Sept.- 4 29 UOY/ Noee@Oss oe dora AD |) = GS No oe@WOucone Oct Lai 52 AQ eS 0222s =O. - 29 1OSs |S GOLR Ee |= = dor 40 Ged OF eae) OC 208) a50 AIG |=dosess- BOWsee5e 29 IO) Se Cssceanliace donee: 40 WG NacaO@ssace Oct 25 R5S 4D) || een asac Sept. 11 36 WHO) Ne seCOscnee Sept. 29 43 178 | Aug. 27 | Oct. 8] 42 Ads lnc d Osea Sept. 16 Al I Wee 3COssenalicee doe 43 OG eed Obese Oct= 9) ) 43 UN) ere 0 Co eaes Sept. 26 51 HWP |e eCOeaas Alle doe 43 1800 2d oss Oct. 15 | 49 45 | Aug. 7} Aug. 28 21 LlSa eee does Octal 45 IDE |i eaOOso ce 2 Oct. 16} 50 46 |...do..... Sept. 4 28 THE SCR ee

este ys eee 4 13} July 31 22 Oe Maa eet. 13 36 | Oct. 8 Fl eae ie Meine Nee 3 14| Aug. 3 20 Gh lege hese 14 Sal Octe all ANCE AD UR Ge) 4 15 | Aug: 6 28 Leiicoe a Sa hbe 27 33 | Oct. 14 Day | Eee ey ns 5 16 |} Aug. 9 iN eo eens baie 44 || 39) Oct 17, Yn ets el Mae 5 17} Aug. 12 41 rls ereheee 33 40 | Oct. 20 Ce ees Se Soe 4 18 | Aug. 15 57 Oa eee ee 54 41 Oct. 23 Ouie eee a aeltaresaeee 5 19 | Aug. 18 59 Telecare 53 42 | Oct. 26 iL else ancl eae 1 20 | Aug. 21 60 A Nie oy a ee 58 43 | Oct. 29 te AI een te | Le iene 1 21 | Aug. 24 AD tiie avers es oe aac ie 42 22 | Aug. 27 49 Lal eu eee 48 Motels 1, 567 441 35 | 1,091 23 | Aug. 30 Gea eee or eee 67 62 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. The results from the above band records are presented in Tables LXIIT and LXVIII, in so far as same could be completed in 1911. The time of appearance of larve and their relative abundance in the respective localities have been graphically shown by curves in figures 18 and 19. It will be noted here that there is practically no differ- ence in the time of appearance of the first larve in the five localities; nor is there any difference in the time of appearance of the earliest second-brood larvz, so far as this could be determined. In account- ing for this uniformity in time of maturity of larve it should be remembered that the seasonal conditions during 1911 were quite Fic. 17.—Mailing case used for shipping codling-moth larve. (Original.) unusual. The spring opened up suddenly and uniformly over the entire fruit belt, and the prevailing high temperature must have started the development of the insects more or less at the same time in the different sections. During 1910, it will be recalled that in these localities a slight difference was observed in the time and rate of appearance of the first brood of larve and practically no difference in the time of appearance of the second brood of larve. We may deduce from these observations that the seasonal development may in years become more uniform in the different sections of the fruit belt than is generally the rule, and that these differences are more in evidence during the early spring than during the rest of the season, while at midsummer conditions are more or less uniform for the whole belt. ) THE CODLING MOTH IN MICHIGAN. 63 TaBLE LXV.—Band records at New Richmond, Mich., 1911, larve collected by G. W. Tibbits. | | Emer- | Num- ; Emer- | Num- NGL Of Pate es ee per gence of ber of Now On Date of | Num- Seaae gence of ber of TECOLG. |e eee vy ; moths, | P27 | WIM |i record.| Collect- | ber of (rooths, | Para: | win- ing. | larvee. 1911, | Sites, | tering || 3 ing. larve. 1911.” sites, | tering | : 1911. | larvee. a 1911 larvee. | | H | LE PTI TIC Pe 25 eee eee teen Ree Ie hE RE EY Se | 24 | Sept. 2} . De Meh ses ere tes aed ste | 7 2| June 28 12 fii | Ps 1 || 25 | Sept. 5 1 Oy Ree ere Meee eerste 3 | Yioilsy al 8 2 1 5 || 26 | Sept. 8 Kodi scree eereael Ik Spee a 8 4|July 4 6 Dh iieeee e 4 || 27 | Sept. 11 1a em Reaeees eee eee ese) 5| July 7 17 10 1 6 || 28 | Sept. 14 TO ae sea erat 1 i 6| July 10 1 10 4 | 4 || 29 | Sept. 17 fol Ses pat eA he leet 7| July 13 17 5} (Gece cee. | 12 || 30 | Sept. 20 UA eee et Seley sa | 14 8 | July 16 21 Peal eee Bees 14 | 31 | Sept. 23 iLL Bp ce seen NE 11 9 | July 19 16 NOM Geers 6 | 32 | Sept. 26 NG} Ge ea [pee 2s 16 10 | July 22 19 11 a) Op i > BBY Seyotin 28) TIDUS Pete ek Dee ial 11 | July 25 17 5 iol 11 || 34) Oct. (2 AG cebieao we Was. 12 | July 28 fl 4 HI 2 |! Soni LOcte 25 EU aoe tal, a 4 133 |) dfiliy Bil Ohi | saeeated ees) Ales 5 30! O@is 3 Shel eee | eee 3 14| Aug. 3 9 le kar an! A 37 Oct. 11 Lad sae loner 5 15 sae: 6 14 Delle ee 12 | 38 oe 14 Geel Nites: eal eae 4 16 wg 9 11 Syl eer ee 8 39 lig. ald 7 el lene ies oe eel ae 4 17 | Aug. 12 20 Soe e eee See 17 || 40 | Oct. 20 Ue ores be ei ea 1 18 | Aug. 15 SAS ete eeoneers one cee 14 | 41 Oct. 23 Sai ese ee ee Sele ly 3 19 | Aug. 18 Pel Fess ee eeu leer 12 42 | Oct. 26 ig Ss sexier pce aE tags 1 20 | Aug. 21 NAF | Seats Bll peace ee 12 43 | Oct. 29 aS eects ea ienctanen 2 1 21 ee 24 1B ANS are Me |e ae 13 |} 44 | Nov. 1 ILS rae a eta etre 1 22 ug. 27 (Oe Petes ripe nner 10 — 23 | Aug. 30 INS | ers poesia abate 11 MOU soos 434 90 9 335 } The band-record curves in figures 18 and 19 are of further interest in that they show a marked irregularity in the rate of appearance of larve in the different orchards, and none of the curves show any natural demarcation between the two broods of larvee which could be used as a basis to separate the two broods. TaBLE LXVI.—Bamnd records at the lake shore near Douglas, Mich., 1911. Emer- | Num- Emer- | Num- Date of | Num- Hmer- gence of} ber of |) .; Date of | Num- | BT gence of) ber of No. of Galt gence of, ae No. of ber of |8e2ce of : it record.| Collect- ber of moths, | P2ta RAEI record collect- ser Of |Shoths,| Pata: | win- 3 ing. larve. 1911. sites, | tering a ing. larve. 1911. Sites, | tering : 1911. | larvee. || : 1911. | larvee. i | June 25 (afer ke eee are 0 | 26 | Sept. 8 SUA pareve ic See ey 15 2} June 28 12 4 5 3 |i 27 | Sept. 11 ZO ae easier ee eet 25 3 | July 1 11 8 1 2 28 | Sept. 14 hot ares ree leer 28 | 4|July 4 14 DF eer: 2 29 | Sept. 17 Oye eer aa eG. ee 28 5| July 7 57 DZ) ewes 25 30 | Sept. 20 32) [Ree saws eeeeeee 32 6 | July 10 23 12 1 10 || 31 | Sept. 23 20ers eee 26 7 | July 138 19 il hig ee eee 4 | 32 | Sept. 26 PAS UH Eis tee Caen eas epee 28 8 | July 16 23 IN (ral eget 6 | 33 | Sept. 29 Ifa fs oes A ae | NEN ee 17 9} July 19 49 Dis || ae 24 | Mil Olen, Til aeeet ee rent ee 7 10 | July 22 48 Gho)i | are tec eae 10 3) || OG TD LN eo ete ee eens eee il 11 | July 25 38 31 1 6 || 36 | Oct. 8 Aa ge Roe NERC FM 4 12, July 28 43 PRM sao Se 21 30 1 Oe 1M TN Hs mes ere tee A Aah bce 12 13 | July 31 44 PX estas cate 18 38 | Oct. 14 ESC Se eRe Ie pa 5 14 | Aug. 3 43 | 19 | iH 23 39 | Oct. 17 1 | ess Sel [ener ete | 13 15 | Aug. 6 09 | dyer we ae 44 40} Oct. 20 (150 | Sere ee eer ere 4 16 | Aug. 9 44 Oils See eee 35 41 | Oct. 23 EY Ne eee Nae eS il | Aves 12 On yee ered ieee 53 4D" | Oct: 26 SUT) | Pes eacen re Seater ay ae 1 18 | Aug. 15 42 Dah vor sell 40 43 | Oct. 29 Oy Leeeaemeleariec esa 0 19 | Aug. 18 Be Ee Sli eee 32 44 Nov. 1 sl eset Se ee 1 20 | Aug. 21 BAN Wicweeietee = aed oo ke 34 45 | Nov. 4 Ol ies Aree ee 0 21 | Aug. 24 Di |Prseyerty 2s | ee ees - 27 46 | Nov. 7 Q lsccsseceescensos 0 22 | Aug. 27 Malice ie ee ae Vie 2 cre pe 28 47 | Nov 10 PR te se aeloeeerees 2 23 | Aug. 30 SN lass |e al.) 32 24 | Sept. 2 AAG et eee | Meee ese 44 VOM sscose 1, 125 287 9 829 25 | Sept. 5 AGM Cel eal pees are 46 | 64 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. Some of the band records might even become misleading were they not supplemented by observations from the rearing experi- ments. For instance the great drop in the curve of the Benton Harbor record (fig. 19) was due to the exposed condition of the apple trees and to severe storms during the latter half of July. Owing to the dropping of over half of the apple crop that resulted, a large number of larvee failed to reach the bands, and many immature larvee Te TTT TTT THT LETT ea ae a PO al ===0 i i ASA { AA AN Lt Ly Iaeasassts Lilt 25 30 5 10 15 20 2530 5 10 15 20 2530 5 10 15 2025 30 5 10 15 20 2530 5 10 15 UURENG AUGUST SEPTEMBER OCTOBER NOV. Fig. 18.—Curves made from band-record experiments in orchards at the lake shore near Douglas, at Douglas, and at New Richmond, Mich.,1911. (Original.) were materially delayed in their normal growth in apples on the ground. There is also to be noted a marked difference in the relative abund- ance of first-brood and second-brood larve in the different localities. Of the total number of larve of the Douglas band records 50 per cent were of the second brood, while of the Pentwater records only 31 per cent pertained to the second brood. [or a comparison of the details of the results for the five band records reference is made to Table LX VIII. et acai ; THE CODLING MOTH IN MICHIGAN. 65 Taste LXVII.—Band records of 1911, at Pentwater, Mich.; larvx collected by S. J. Taylor. | | | Emer- | Num- | Emer- | Num- is Emer- + Emer- Lr Date of | Num- 'gence of} ber of + -| Date of | Num- gence of) ber of joo collect- | ber of eS f para- | win- eel collect- | ber of see oh ara- | win- | | ing. | larvee. |“jo1,.’| Sites, | tering Came. | Jarwe: ere ies sites, | tering | =) |) 19tt | laryvee: > | 1911-- | larvee. | | | | | 1 | June 25 6 1 eee 5 | 27 | Sept. 11 Rol keene ere paar: 18 2| June 28 10 Di aeteae 5 28 | Sept. 14 ey ere fa her eateae 2 | 3|July 1 56 44 2 10 29 | Sept. 17 file oe eedln ae Pot 14 4} July 4 24 Guerre 15 30 | Sept. 20 The caf el oa 16 5| July 7 18 PL (et tees 7 31 | Sept. 23 Vial ee eet Oe 17 6 | July 10 17 Biles eres 13 32 | Sept. 26 tl Wa ci oil We ee 22 7| July 13 37 31 ht eee 6 || 33 | Sept. 29 Gl eee, 2 Sil ese a 23 8 | July 16 46 Bia (are ene ae 12 34] Oct. 2 1S \o) ee ete eee ca 13 9| July 19 o7 Sho ae ceed 19 30 TOCta oO TOR Pea se aD oe ee 10 | 10 | July 22 73 (37) (eek eee 6 36;|"Octs 78 Ei Sel heared 1 ec ares 5 11 | July 25 38 | DUS eat ces 9 || a6 | Oer wh di eee eee reiee tee 13 12} July 28 | 39 | SA ae 8 | 38 | Oct. 14! 11 Ss) ae eee aan ae | ll ff uly 3k |... 52>| 2 eee 27 II 39 | Oct. 17 | oie dks Paseunw | Seen 14} Aug. 3 | 45 Pd il Glee 24 40 | Oct. 20 LG es egtecroetes ees: | 15 15 | Aug. 6| 38 | 1) Sl sara | 27 4] | Oct. 23 PAs Vie Se aS eae er 2 16 | Aug. 9 | S| Dye iva eet 27 || 42} Oct. 26 By | Hees Meme ren| eee mae | 3 17 | Aug. 12 | 16 Doles eu aat 14 43 | Oct. 29 i ent ea 3 lee | 2 18 | Aug. 15 | 42 | (al fegge epee 3 44| Nov. 1| 7 sigs a | ec oO | 19 | Aug. 18 | Aon eer eee epee oes | 28 | 45 | Nov. 4 (7 (ee eae EAL Ae | 0 20 | Aug. 21 7 eee ae sae | 26 }| 46. | Nov. 7 1 Pee asl OS lee 21 | Aug. 24 Gal eee atte Pus alagalea Se 17 47 | Nov .10 Ones Epstein 0 | 5) | LASTS || aap eae Euete pee 250 peese Nowels (cs ollse. se eS oe 0 23 | Aug. 30 ZO eee sae ee ee 26 | 49 | Nov. 16 | CON ies a a be 0 24 | Sant. 2 Doe teeta oan as | 25 || 50 | Nov. 19 | 1 5) (Ere ee a Ss ee | 1 25 | Sept. 5 ey) ees ee 15 || | fe ! | | 26 | Sept. 8 AGg eel GaN estes | 46} Motalis nee | 1,044 pu 2) 670 Tasie LX VIII.—Band records of 1911; summaries of Tables LX III-LX VII. New Rich- Benton Wisk oe Douglas. | Lake shore. | Sn. le cea noe Pentwater. | | Aver- Observations. - | 1 | | age per Total Ren | Total Pare Total re | Total Per Total Pee cent. num- eS ant ee eens a num- Ron cent. | ber. cent. | ae: cene. | jer. | cent. hon cent. | | —— | —_—_____ _ Larve collected from | | ei ithe bands=-2 oe * 517 | 100.0 | 1,125 | 100.0 434 | 100.0 | 1.567-} 100.0 | 1,044 | 100.0 100. 0 Moths emerging, 1911.. Seti 6h 280 te 25.5" SO 20.7 | 441 28.1 3/2} 35.6 | 29.5 Parasites emerging 1911) LOEW 3: 0 | 9 | -8 | 9 Zags) 39 2.3 2 2 | 1.8 Larve of the first | | | DROOGS eae ee eee 261 | 50:5 779 68.9 | 268 61.7 | 1,008 | 64.3 717 68.7 | 62.8 Transforming larve of eae | YS GeDROOO Ss ee. = 91} 34.9 287 | 37.0 $0 | 33.6 441 43.7 372 | 51.9 40.0 Wintering larve of | | | first-bro0ds.. = 170 | 65.1); 488 63.0} 178 66.4} 567 | 56.3 345 48.1 | 60.0 Larve of the second | | | IDRQOG es Se ee a 256 49.5 350 5 | 166 38.3 559 35. 7 O28 | -oLsouli oh. Wintering larve of | | | first and second | DEOOUS 22.222 Seer 407 | 78.7 | 829 13.7 Sih (ers |) Wa ED! | 69.6 670 64.2 | Tet! The averages for the different observations show that from the total number of larve only 25.5 per cent transformed and issued as moths in 1911; adult parasites issued in 1911 from 1.8 per cent of the codling-moth larve; 62.8 per cent of the larve were of the first brood and 37.2 per cent of the second brood; of the first-brood larve 40 per cent transformed and 60 per cent wintered; of both the first and second broods 72.7 per.cent of the larve wintered. SUMMARY OF SEASONAL-HISTORY STUDIES OF 1911. The prevailing high temperature of the season produced a marked shortening in the time of development of the codling moth. The deviation from the average conditions is only slightly noticeable within the separate stages, but becomes. strikingly marked for the 66 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. whole life cycle. Thus the time of hatching of the earliest larve of the second brood came 21 days ahead of those for the previous year, and the time of hatching of the second-brood larve extended over an unusually long period of two and a half months. The second-brood larve were exceptionally abundant, being in some orchards equal in numbers with those of the first brood. In figure 20 a summary is given in a graphical form to illustrate the progress of the development of the codling moth in the course of the whole season of 1911. Li oc ANCA A a Aaa AAT A A ic mn i eA ie A Hil APD SCAN nn A ie oo0 Ma IEAM WVHA FALUN RLU Nn cA ae A NLU ct adda a A cnn Li AAA ec cc x LC a a oN IANA MEET NATTA 89 mu 0 LAM UL TE CT NTT PHT HUH UTNE INN Wear vA a CU EL Le Lac ee in ANH a HK i AM can : ih A i i Ms AA A A A | | ANDAs CN Hh “OnHTT ETE EH HE PHRTEC ECT eRe 25,3075. 10 15 20°25.30) & 10 15 20°25 30) 5) 0) 120,25) 80) SO. 1b 2025 Oe Oba CHENG AU GUST SEPTEMBER OCTOBER NOV. - Fiqg. 19.—Curves made from band-record experiments in orchards at Pentwater, Douglas, and Benton Harbor, Mich., 1911. (Original.) WEATHER RECORDS FOR 1909, 1910, AND 1911. Considering the variation in the time of transformation of the cod- ling moth during the three years of observation, it becomes evident that the insect is largely governed by climatic conditions. This is only natural, since phytophagous insects, depending upon the development of their host plants, must to a certain degree be governed by the same phenological laws that govern these plants The earliest codling moths of the spring brood generally appear at a THE CODLING MOTH IN MICHIGAN. time shortly after the blooming period of apple, so that the early lar- ve will hatch after the setting of the young fruit. A full considera- tion of climatic conditions during the years 1909, 1910, and 1911 is therefore given for a better interpretation of the life-history studies. 10 15 20 &5 NOVEMBER (Original. ) 5 10 15 20 25 nd brood 4 SEPTEMBER | OCTOBER 5 10 15 20 25 brood! moth C) 10 15 20 25 5 = s) ae & Ae) o>? = = Leora ees ere VU aa ra Diagram illustrating seasonal history of the codling moth as observed during 1911, at Douglas, Mich. 20. cen 5 10 15 20 25 5 10 15 20 25 5 10 15 20 25 A self-recording thermometer of the type generally used by the United States Weather Bureau was kept in the rearing shelter throughout the seasons of 1910 and 1911, and the records of the tem- perature conditions are given in Tables LXIX and LXX in degrees Fahrenheit. The average daily temperature in these tables repre- sents the averages from hourly readings for each day. The readings 68 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. of maximum and minimum degrees of temperature were taken from a special maximum and minimum instrument. Daily record was also kept on the general weather conditions. For the preparation of the following account of climatic conditions the writer has in addition made extensive use of thereports of the United States Weather Bureau. The season of 1909 was characterized by a cool and wet April, by heavy rains during July, and by an exceptionally warm Novem- ber. During the month of May rather cold and dry weather pre- vailed. During June the temperature as a whole was seasonable, although there were an unusually large number of rainy days. The temperature for July averaged slightly below normal, and the pre- cipitation was far in excess of normal. During August the tempera- ture averaged several degrees above the normal and the rainfall was slightly in excess in the southern parts of the peninsula. September, on the contrary, was marked by a somewhat low temperature and a deficiency of precipitation, October was unseasonably cool and rather dry, while November as a whole was unusually warm. The spring of 1910 in many of its features was unprecedented, as is well stated by the United States Weather reports for March: The excessive warmth, the extreme dryness both as regards precipitation and rela- tive humidity, the large number of clear days with bright sunshine, the early disap- pearance of snow and ice, the light wind movement, and the absence of serious storms makes a history for the month (March) without parallel since the beginning of the official records. Never since the Weather Bureau was established has there been such an early opening spring. As a whole, the conditions that prevailed at the close of the month were those usually experienced from three to five weeks later. The warm weather of March continued through the first two weeks of April, when many deciduous fruit trees were out in full bloom. Following this warm weather, at a very critical period for the orchards, a drop of temperature occurred, which was accompanied by a storm with rain and snow and severe freezing. The cool weather which prevailed during the latter half of April continued with slight interruption throughout the month of May and the first half of June. Vegetation was not merely greatly retarded, but badly damaged, and the season was exceptionally backward. In striking contrast to this low-temperature condition came warm weather, which was rather above normal, extending over the latter half of June and all of July. August was fairly normal. During these last months precipitation was below the average, and clear bright weather prevailed mostly throughout. The weather conditions during September and October were fairly normal. A marked drop in temperature set in during late October, which brought most insect activity to a standstill for the rest of the season. The month of November, in striking contrast with 1909, was cloudy and cold. The uniform spring of 1911 was very favorable for the development of fruit and leaf buds, which were not unduly forwarded. The weather during April was rather more severe than usual until the last THE CODLING MOTH IN MICHIGAN. 69 week of the month, when a pronounced warm spell set in, which advanced rapidly the growth of vegetation. The mean temperature for May was decidedly above normal, and an abundance of sunshine prevailed. The United States Weather Bureau pronounced the heat for the month unprecedented. Thunderstorms were frequent, accom- panied by high winds and excessive rainfall. This weather condition continued without interruption throughout the greater part of June, when severe storms occurred, which caused great damage to orchards and the fruit crop. During the period from the 11th to the 18th, at the height of the emergence period of the spring brood of moths, a markedly low temperature prevailed, accompanied by frequent rains, which caused a sudden and prolonged delay in the appearance of the moths. The weather conditions during July were also very excep- tional. The first week of the month was marked by excessive heat and great dryness, while during the latter half of the month decidedly cold weather prevailed, with frequent local showers. August in most respects was normal, while September was marked by sharp alterna- tion of warm and cold periods and a frequency of rainfalls. During October, and particularly during November, cool weather prevailed, which delayed considerably the time for the maturity of many second-brood codling-moth larve. TaBLE LXIX.—Temperature records taken in the outdoor rearing shelter, showing maxi- mum, minimum, and average daily temperatures, Douglas, Mich., 1910. April. May. June. July. August. |September.| October. | November. ees el a al Let et lel el lee! ldlel-. =} (0) = 2) = 3 oO 3 3 2) 3 Oi1Ssisio;sis|ois ) ee gee a See | Slee | Slee | SP lBle| flele| f\sig|¢ Sees eosin mio fs | a | oe lie la | ole lol Olek ia) Oo | Mia] o a icc |e asia | icp ete tet cate ies aN tn| eS et fous ics est ete | coiest b= Vacs pest) US | cgi alsiel2|slsi2lel|s/4jels\=|3/5| 4 l2/s| 4 j2|s| 4 |S |8| < | rises col tar ace Pe Os Pees OP a | OSPAD cu Fins | OUP es Outre Oo FAN |: OUP | OAT SP 1h. BRIS SY Byt 112 Fe | OUT Bee oP da? A a 20 Wa db no 1..| 61) 39/49.9| 64) 48/54.5) 51) 41/45.2) 87] 59)72.5| 74) 5668.2] 70) 5059.5] 65) 44/58.0) 50) 3846.9 2.-| 71) 42)55.7| 54) 43/50.5| 46) 39/42.5) 94] 61/77.0| 80) 6269.3] 74) 46)61.5) 66) 4455.6) 42) 3437.4 Baal ete 48/59. 0 54{ 40/45.3| 54!) 42/46.7| 81 62,71. 1) 78| 66:72. 5| 72 62/66. 4 83| 5868.2) 44 28 35.5 4..| 72 5969.0} 49) 36/43. 4 64) 47|56.0; 80 58 69. 0} 71) 5065.2) 67 60/64. 0 66) 6364.5) 46 26 33.4 5.-| 74! 50/64.6} 53) 33/43.8] 58! 44'51.8) 86 54/70.4) 72) 5063.3] 72] 64/70. 4] 72| 57/65.0} 40) 32/36.0 622), 58) 33/44: 1) 58) 33/47. 7 56) 43/47.1| 82 62|72. 6; 74) 48 62.2) 73) 60/67. 4) 57) 39 47.7) 32) 3030.2 7--| 41} 30\36.0 60; 38/53. 0 o7, 44/49. 9| 77 60,69. 6 75| 5664.6] 81) 54/69. 0) 62) 34/47. 8) 46) 31/37.0 8--| 69} 29/51.2} 53) 46/49.9) 67) 42/56.9| 88 58|/76.6) 79) 5466.9) 7é| 61/68. 6 61) 40 53. 8| 46 3437.0 9..| 59} 43)/49.7| 60) 41/49.5) 74) 5363.7) 89 65)74.2) 74, 6469.6] 60) 4254.6) 58 4451.7) 56) 4048.5 10--| 71} 38)56.2} 60) 40/50.5} 73) 5062.2) 72 6568.7) 72| 5667.2] 64) 39)52.9) 58) 36)/49.0) 44; 3037.0 11 58| 35)50.0} 54) 36/44.8] 66 50,56. 4, 81, 6773.4 77) 5064.2) 77| 43/62.5) 66, 54,61.2) 36) 30/32.7 12 57| 32/42.2) 48) 32/42.6) 70) 46/60.0| 78 6469.6 82) 5267.9) 74) 5060.8 60) 4253.1) 38) 3436.0 13 59| 29145.0} 47) 34/40.9| 78) 5364.0) 76) 5667.0) 81! 5970.1] 64) 46153. 6) 69) 40/53. 9} 39) 33)35.2 14 76, 41'60.2 53) 29/41.8} 76) 52/65.6) 82) 58/71. 7; 78) 6068.7} 64) 4554.5 71) 52,60. 4) 33. 3031.4 15 73) 61/67.2} 65, 37/51.5) 73) 54/64. 7| 82} 68)75.0| 84, 63,73. 4 70) 43 56.7 61) 50/55. 2) 34 31/32. 9 16 74| 39/58.9| 70} 46)58.0! 80) 55)69.8) 82 64/72. 5) 80) 6872.6) 72 47/59. 4 73\ 58/64. 3) 33 28/30. 7 17 52] 37)/43.1]) 58] °47/53.6) 80) 67 73.1) 77, 5867.7, 80 6472.3) 66 52/60. 3 78 52/62. 0} 30) 28/28. 2 18 492) 34/38.0| 62) 46/54.3} 80) 62/70.1! 76 5363.6 74) 5968.0) 74) 55/63. 7] 81) 53/64.9) 31) 29/30.0 19 45; 3940.9 rat 52/61.3) 74) 60/68.3) 76) 51/64.0) 76) 5363.9) 68) 53/57. 7) 78) 58)/66.9] 38) 24/29. 4 20 48) 3843.7) 68) 54/61.0) 74 60/67.8 77, 5669.8 74 5566.0 67) 5060.2 57) 4650.4) 43, 2332.4 21 62} 34/46.9| 77; 54/62.3) 87| 63)/76.6 79, 65\72.3, 83 6073.4 74) 4959.5 53 4649.4) 36 30/33. 0 22 66; 3953.4) 74 5262.4) 86; 66)75.5 7 66,68. 5) 83) 70, 76.0) 72) 45|59.3 52) 46/48. 8) 40) 30/34. 8 23 37 313 -8| 62) 4552.8) 86] 72/75.7| 84! 66)74.2) 78] 63)70. 7 66) 5760.0 61, 39|48. 4 47 32/38. 5 24 43) 3237.4 58| 4552.3] 84] 60/73.3} 80 64/70. 8) 82) 7376.9) 68) 5760.4 62) 45/53.9! 42) 34/38.0 25 42) 36/38.9) 56) 438/48.5) 84) 55/69.5) 79 62)71.1) 78) 58 68. 4: 57 48 54.7 58 40/50.1) 40) 30/36.1 26 57| 36/44.2) 50 42/46. 2 81} 55/70.2; 85) 59 73. 4 68) 5060.4 65 45|57.1 60, 44/51.0 44| 24.33. 2 27 54| 4045.6) 60) 3950.4) 74 61/67.8 77: 64/70. 2 71| 48 60. 8 58| 53/55. 1 50 34/42. 6] 38 32/34. 1 28 63} 42/53.5| 74) 40/62.1) 78) 53/66.2; 82! 59/70. 9 75| 5364.1) 64) 4352.6 34 30/32. 0 36 32/33. 3 29 74, 56/65.2|) 62) 46/54.5) 80) 56/69.9) 80 61/72. 8 76; 5867.0) 66) 42/55.0) 35) 30/31. 8) 31) 28/29.8 30 56} 44/47.7| 47) 43)/45.0) 83) 60/72.3, 72) 60/67.2) 81) 60,70 4) 72| 51/64.0) 52) 29/43. 4] 33) 28)30.3 ike iree | ata 49) 40/41 O---- a | ae | 72 48/02. 3 76 59,66 3. eral | 53 32/47. 4)... vee]eses Notr.—The records from Apr. 1 to 20, inclusive, were taken from Mr. Tillinghast’s records at Douglas, Mich. T0 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaspLteE LXX.—Temperature records taken in the outdoor rearing shelter, showing mazi- mum, minimum, and average daily temperatures, Douglas, Mich., 1911. | May. | June July | August | September. October. November. ' | | a alas leaulaes al ss ala ira (= glal eldlal a lelel ele cele See | 2s | se She Ee \= a | 8:)-e:b 2 8 Pe | 48 sabe ee ees tS hei hs ey fe (= ai ee ice S a c= 5 | iy |= Sha eee i= 5 2 = = es) a = > re — > oS = > 3S — Ss [ia — > 3 — > 3 = > ei fey rm ese ams Wd Pee r= ed at eg Pi (cee) ew et cs) Ome | ee 4“ /ate/]4 _——— —— | —_} —_ | } eS SS poe Zl Ni or |e Fler Se FEI TT “ror | °F | °F. be Pi eat 2s are ag ag Ga ee A ee 1... 58) 32) 41.5) 70) 49) 61.0) 89) 7| 79.2) 76 66) 70.8) 83) 55) 69.5) 54) 50 51.8 41) 28 35.3 2.-- 44) 33) 36.5) 69) 48] 63.0) 89] 75) 80.8} 73) 59 66. 2) Té| +54) 67.1] 60} 46) 52.7; 33} 25) 29.7 3--- 52) 35) 42.9) 80) 60) 66.9) 92 73) 81.2) 76, 55) 66.3) 70 49} 59.8) 69 44/ 54.0 41) 30 342 4.... 59 38) 43.3) 84) 62) 70.8) 94 88 83.1) 81) 63) 70.2} 81 47} 65.2) 60 49) 55.4 40) 31 35.9 d--- 59 31) 43.6, 75) 52) 65.2) 95 78) 86.0) 85 69) 73.7) 75 61) 65.7, 50 37| 46.7, 48] 38 41.8 6... 72) 26) 51.9) 70) 59) 63.2) 79, G68) 73.7) 86) Gl] 74.3) 63) 59) 60.8 62) 46, 52.3. 50) 42) 49.5 (hea Gye ac Bik ey 63) 54 60.8) 85 65) 744 88 64 77.0 73 57| 62.2) 53) 36 46.0 44) 40 41.8 sees) 7A) Sear Cee: 75) 53] 65.9} 89 65) 78.9] 74! 69) 69.4) 70) 56] 67.9} 56) 31] 44.5) 50] 33) 40.2 922] 16) 551/62. 4 St 62) 75.3). 89 73) 79.7) 84 57) 70.7, 64 53} 60.1) 63 38 49.6 47) 33) 41.3 10..-| 82, 54) 68.9) 86) 67) 74.9) 89 73) 77.2) 87, 62) 73.1) 71 53) 61.9) 60, 48) 52.7, 59) 48° 52.4 11... 64 53) 60.3 78) 64 66.2) 87 71/ 78.2) 78 G64 67.4 7 08, 64.9 60 46) 52.0 72} 46) 62.4 12..-| 68 42) 52.5) 64) 53} 59.2) 78 | 67.1 73) 57, 65.3) 62 52) 55.4. 59) 43) 50.0 39) 1 20!23.4 13 65) 36) 48.5 66) 51) 58.8) 78 59) 70.8) 78) 60) 67.0) 67) 48) 56.3) 64) 42) 51.9 25)120!23.2 14 75| 47) 61.4 72| 53) 61-2} 79 68) 69.1 81! 67) 73.4) 70 50) 60. 6 59 48] 53.2) 33) 24) 27.2 15a) ON Sor 687 72 53 63. 3) $2: 57] 70.6) 7 67| 69.6} 72) 61 66. 2| 63 47) 53-0. 34, 26 30-4- 16..| 79} 58) 6&8 68) 60) 63.4) 72 63) 65.7; 81) 69 73.3) 73) 50) 62.8) 76) 50) 63.1; 34) 21) 27.0 ee 79, 64) 71-9) 69] 60) 62.3) 72 54) 61.9) 77| 67) 70.9) 82) 53] 68.5| 57 42 53.7; 48] 30} 35.5 18. 841 64 74.7; 73] 5a) 63. 7 79 54) 68.4 78 65) 66.31 74 61/ 66.7) G4 41/ 53.3) 34) 26 28.5 19.-{ 8& 72) 79.2) 78) 55] G8.1[ 75 64) 67.7; 69) 51) 60.0) 64) 48] 59.2) 54) 46 50. 2 2 27, 29.8 20. 85, 59) 70.0 76) 62 69.5) 77 53) 66.4; 70) 49 60.9 68) 45) 57.9) 53) 45) 47.9 34) 28) 31-6 Fie 74 61) 69.8, 79) 55) 70.1) 72 64) 66.0) 80) 53) 68.5) 68 47| 56.3} 51) 43) 45.9 34) 28) 31.3 22. 76, 60} 65.0| 85; 69) 76. 9} 7 53) 68.0} 72); 66 65.3) 70) 44) 56.2) 48 42) 44.3 37| 2S 33.0 23% 70, 60 61.4 87) 67| 77.3) 76, 56 63.7) 71) 51) 59.9) 72) 50 62. 4 46 42| 44.5) 38) 28] 32.6 2A. 72) 54) 58.0 82) 59 69.7) 68 53) 59.6 70) 56) 59.3) 67; 59 62.0) 51) 41) 45.3, 31) 26) 28.0 25 82, 57) 70.3 80) 69) 73.1) 66 53) 59.8 72) 45) 57.9) 60) 50) 56.9) 57 41) 47.4 39) 30 34.7 26 82) 63) 72.1) 83) 68) 74.9) 71) 51) 62.3) 78) 49) 63.4) 63) 43) 53.9) 50) 32) 39.1) 48) 34) 38.4 27..| 89 64) 78.2) 77} 67| 68.6) 77, 49) 64.2) 79) 59 68.5) G68) 47) 61.0) 44) 30 35.3 47| 32) 38.6 28 68 Gl) 62.9, 64 58; 60.3) 78 56) 69.2; 69) 59 62.7) 63) 42) 54.2) 47 33) 40.7; 38} 26 33.6 29 74- 55) 64.5 74 48) 63.1) 78 61) 63.3) 66) 46 55.7; 62, 47) 53.9) 51) 2 46.5} 32) 21) 27.7 30..| 75) 52) 65.3) 83] 47) 74.3) 82) 62). 73.7| 74) 44 58. 2| 56! 46) 50. 6 48) 41} 43.9 34 24 Bl ST hal GY EE 6020/4 86 63) 76.0) 74) 53 59. 5) een ee | Lee 4 25) A012 ee 1 Temperatures below 20° F. not recorded. COMPARATIVE LIFE-HISTORY STUDIES FOR THE SEASONS OF 1909, 1910, AND 1911. On considering the seasonal variations in the time of transforma- tion and the relative abundance of the codling moth it is evident that the climatic conditions, and mainly the temperature, are the direct governing factors. Sometimes a scarcity of fruit may mate- rially reduce the normal abundance of the codlng moth. The effect of climatic variations upon the life of the msect is particularly noticeable in the spring, when the relative earliness of the season is followed by a corresponding change in the time of emergence of the moths. From the curves of figures 1, 6, and 14, which represent the time of emergence of the spring moths for the respective years of 1909, 1910, and 1911, with temperature records for the last two years, it will be noted that under prevailing uniform temperatures the emergence for the main portion of the moths becomes limited to a short period, as occurred in 1910, while on the other hand under fluctuating temperatures the emergence is very irregular and extends over a much longer period of time, as observed in 1911. THE CODLING MOTH IN MICHIGAN. 71 The time of the emergence of the earliest moths has closely fol- lowed the time of : GeeCe of apples and occurred from 5 to 10 days after the blossoms noord (Baldwin apples). By adding. to these figures the time of flight of the moths previous to oviposi- tion and the time of incubation of the eggs 1t was found that fully three weeks elapsed before the hatching of the earliest larve of the first brood. In 1909 the moths commenced to appear at a normal time, but were somewhat delayed in reaching a maximum of emergence. The season as a whole was fairly normal. The late fall, together with MAY JUNE JLILY AGUEEST |SErPTEMEE Se omar 2005. lO l5e2002501 51 10. 15 20:25 | 5 10 15 20.25 | 5 10 15 is. gb oad Alogi hg rr i ty Gf) OF Jes INiiahia it Vali | ANAL Fic. 21.—Diagram showing time of emergence and relative abundance of spring-brood and summer-brood codling moths, and blooming period of apple trees, during 1909, 1910, and 1911 at Douglas, Mich. (Original.) other favorable influences, produced a development of a very large second brood of larve. Of the total number of larve for the year, 43 per cent were of the first brood and 57 per cent of the second brood. This occurrence was perhaps directly due to the unusual rate of emergence of the moths of the summer brood. These com- menced to appear at the normal time, but already reached a maxi- mum during the early part of August (fig. 21) instead of the latter part of the month, which is the general tendency as shown for 1910. In the band-record curves of figure 22 is shown a corresponding rate in the time of maturity of larve of the second brood. The maximum in the first brood of larve occurred comparatively late, ee, DECIDUOUS FRUIT INSECTS AND INSECTICIDES. which in turn reduced the percentages of transforming larve as against the percentage of wintering larve of the same brood (see Table LX XT). The occurrence of an early maximum of larve in the second-brood larvee was due to the early rate of emergence of the moths of the summer brood, and to favorable climatic conditions. During 1910 the codling moths of the spring brood were delayed in the time of emergence of the earliest individuals. The larger number of moths, however, emerged very soon after the first appear- ance of moths, so that for the rest of the season the dates for the occurrence of the separate stages were about normal. The summer moths commenced to appear July 26 and reached a maximum of SEINE of) EN? AUGUST |SEPTEMBER| OCTOBER |INOVEMBER 5 10 15 2025 | 5 10 15 2025 | 5 10 15 2025 | 5 10 15 2025 | 5 10 15 2025 | 5 10 15 2025 Fic. 22.—Diagram showing time of leaving the fruit by the first-brood and second-brood larve of the cod- ling moth during 1909, 1910, and 1911, at Douglas, Mich. (Original.) abundance during late August, which has been observed to be the general rate of emergence for the brood. In 1910 the codling moth was naturally limited in numbers as a result of the small crop of apples, and to this must be ascribed the reduced size of the second brood. Of the total number of larve from the band records, 73.2 per cent were of the first brood and only 26.8 per cent of the second brood. In some sections of the Michigan fruit belt the apple crop was so limited that only one brood occurred, the fruit having dropped before the second brood developed. The spring of 1911 opened at a normal time. The temperature during the latter part of May and all of June was on an average exceptionally high, and this condition forwarded the development of both plants and insects In a very unusual manner. The moths commenced to emerge at a normal time, as comnared with pheno- THE CODLING MOTH IN MICHIGAN, 73 logical developments. In the course of the emergence period part of the moths of the spring brood were hampered by cold rains, which set in during the middle of June and caused a somewhat pro- Jonged delay for about one-half of the moths. This irregularity in the development of the insect produced an unusual effect upon the time and rate of occurrence of the separate stages for the rest of the season. This is noticeable from a study of the curves of figure 21 for 1911. In the summer brood there occurred an abundance of moths at the very start of the emergence, which was followed by a decrease in number as a result of the delay found in the spring brood; then again an abundance of moths appeared during the first half of August as a result of the emergence of the later half of the spring brood of moths. The prevailing high temperature advanced the earliest developing insects to the extent that the second-brood larvee appeared three weeks ahead of those of 1910, and further prolonged to a very unusual extent the time of emergence of the summer moths, the period of egg deposition, and the period of hatching of the second brood of larvee. The large fruit crop, together with the high temperature, favored the development of a large second brood of larve. For the total number of larve collected at the Douglas band records 50.5 per cent were of the first brood and 49.5 per cent of the second brood. TaBLE LXXI.—Summary of results of band records for 1909, 1910, and 1911, at Douglas, Mich. Percentages for— Observations. aE 1909 1910 1911 Mo insiemenrinre nemsamesseason: seek eke ee os Sg oboe: Veet S4 Osean O525 17.6 Mothsremenrcineahesfollowimpseasonens. 2] se oe ee. 55s 0 | SOR (al eco eee Motalkemenrcencewoiemo tnSesets eye eo ee ae ee ee eee Serra OS=1574 |S O0E 27 | exes ence Wiiitterincsanycortotabandrcollection= <2 22-225... = .0 22.5. knee ence oe SEE) ee 78.7 Wigiatenincglaiguce Kalle daly (tOS tes seni nee sn ee Se 246 SOR Wea ee ALASTGIZe Cal Aine eae ees ens es eee At SU eek ako coe ee ee] 6.6 | CL fon ie er Rela iivesproporilon-omest-pLoodslanyce...- 222. 2.2.2. eee oe ee ee) | 43.1 Wane 50.5 Relaiivepropornonctsecond-prood lanvices 25-22... 228) ee | 56.9 26.8 49.5 (ransionmiMnesarviesOtmarStHONOOM se the ee ee a) we uk ee Piero 34.8 34.9 NanierineslamvecotentsteprOOdsn, saree oe ee a ae eo 2g ee | 66.8 65. 2 65. 1 The results from the band records for the three vears at Douglas show that of the first-brood larve about one-third transformed the same season and two-thirds passed the winter in the larval stage, as do all second-brood larve. (See Table LXXI.) INSECT ENEMIES |! PREDACEOUS INSECTS. Several predaceous insects have been found to attack the larve and pup of the codling moth. Of these a small black beetle and its larva, Tenebroides corticalis Melsh. (P]. III, figs. 4, 5), belonging to 1 For information relative to the bird enemies of the codling moth, see Yearbook of the Department of Agriculture for 1911, pp. 199-208, ‘‘ Bird Enemies of the Codling Moth,” by W. L. McAtee. TA DECIDUOUS FRUIT INSECTS AND INSECTICIDES. the family Trogositidx, has been found to constitute one of the most important predatory imsect enemies of the codling moth. The slender and flat form of the larva and also the depressed shape of the beetle enable the insect to penetrate into narrow cracks and crevices in search of prey. Both the larve and beetles have been found in the cocoons of the codling moth, having penetrated the walls of the same and destroyed the host. Full-grown larve and beetles have been collected in the late fall and in the spring, which would indicate that the insect passes the winter in both stages. The white and deli- cate pupa was once observed under the bark in a small cavity, which must have been made by the larve previous to pupation. There are several species of carabid beetles that have been found under the bands on apple trees. Of these Pinacodera limbata De}. (Pl. III, fig. 3) and Platynus placidus Say were seen to destroy the larve of the codling moth. Mr. W. Postiff collected in 1910 one specimen of Tenebroides castanea Melsh., which also was destructive to codling moth larve. These specimens were kindly determined by Mr. E. A. Schwarz, of the Bureau of Entomology. In wind fallen apples the codling moth larve are sometimes attacked by wireworms (species not determined), which have been found in wormy fruit. In confinement the wireworm larve fed freely upon codling moth larve, even after the latter were removed from the fruit. The larve of a lacewing fly (Chrysopa sp.) were often observed in the act of absorbing the contents of the eggs of the codling moth. In the rearing shelter these insects were regular pests, in that they would destroy the eggs in the cages under observation whenever the egos were left exposed. In the orchards the larve of the lacewing flies are very common and no doubt they play there an important réle in checking the codling moth. PARASITIC INSECTS. Among the native hymenopterous parasites of the codling moth Ascogaster (Chelonus) carpocapse Vier. (PI. III, figs. 1, 2) is the most commonly observed. It has been collected in the States of Michigan, Pennsylvania, Maryland, Virginia, and Nebraska, and will probably be found in most localities where the codling moth occurs. The species was originally described by Mr. H. L. Viereck + from specimens col- lected at Douglas, Mich., in 1908 by Mr. R. W. Braucher. The writer also reared the insect in abundance at North East, Pa., in 1908 and 1909. The band records in 1909 at Douglas, Mich., showed that 6.6 per cent of the codling moth larve were parasitized, and in 1910 the sep- arate band records showed the following extent of parasitism: New Richmond, 7.7 per cent, Saugatuck 4.7 per cent, and Lake Shore 7.25 per cent. 1 Proc. Ent. Soe. Wash., vol. 11, p. 48, 1909, Bul. 115, Part |. Bureau of Entomology, U. S. Dept. of Agriculture. PLATE III. INSECT ENEMIES OF THE CODLING MOTH. Fig. 1.—Ascogaster carpocapsx,a hymenopterous parasite of codling-moéh larve. Fig.2.—Cocoon of Ascogaster carpocapse within a cocoon of the codling moth, enlarged twice. Fig. 3.—Pin- acodera limbata, a predaceous beetle destructive to codling-moth larve. Figs. 4, 5.—Tene- (Orie eae beetle and larva, which feed upon the larva and pupa of the codling moth. riginal. ER RE TE St pre eee oa ee THE CODLING MOTH IN MICHIGAN. Cs) The time of emergence of the adult parasites coincides with the time of emergence of the two broods of the codling moth. (Tables LXXII and LXXIII.) Like the host, the parasite is evidently two- brooded or possibly has a partial second brood. TaBLeE LXXII.—Time of emergence of the spring brood and the summer brood of Asco- gaster carpocapsx at Douglas, Mich., 1910. SPRING BROOD. T i Number | Date of | Number| Date of || Number} Date of | Number]! Date of of para- emer- of para- emer- of para- emer- ] of para- emer- sites. gence. sites. gence. sites. gence. || sites. gence 2| June 22 9 | June 27 4} July 2 Ll edialyen 9 9 | June 23 2} June 28 ee July 3 1| July 15 5 | June 24 14} June 29 5| July 5 11 | June 25 5 | June 30 3| July 6 86 10 | June 26 3 | July 1'| 1| July 8 SUMMER BROOD. ; | 1] July 26 | 2} Aug. 11 | 1} Aug. 19 || 3 | Aug. 29 1| July 30 | 3 | Aug. 12 5 | Aug. 20 1} Aug. 30 2| Aug. 2 || 3| Aug. 13 | 6| Aug. 22 || 2 Sept. 5 db Aus 47} 3 | Aug. 14 2} Aug. 23 1| Aug. 5 || 6 | Aug. 15 2| Aug. 24 || 72 a0) ANE viel 4} Aug. 16 3 | Aug. 25 2} Aug. 8 || Sel ALIS 7a) 1| Aug. 26 |iee 4| Aug. 10 || 2| Aug. 18 | 1| Aug. 27 || TaBLE LXXIII.—Time of emergence of spring and summer broods of Ascogaster car- pocapsx at Douglas, Mich., 1911. SPRING BROOD. Number | Date of | Number| Date of | Number| Date of || Number | Date of of para- emer- of para- emer- || of para- emer- of para- emer sites. gence. | sites. gence. | sites. gence. || sites. gence. cS ae eas I EE ene | eee 1| June 2 | 3 | June 12 | 3 | June 19 | 2} June 28 4/ June 5 || 2| June 13 | 7 | June 20 1 |. June 29 7| June 6 |! 4} June 14 | 4} June 21 1 | June 30 1] June 8 || 5 | June 15 ! 2| June 22 4| June 9 | 2{| June 16 | 6 | June 23 83 | 7 | June 10 | 4 | June 17 | 4| June 24 1) June 11 7| June 18 ! 1 | June 26 | SUMMER BROOD. | | ! || 1} July —9 || 6 | July 21 | 5 | Aug. 4 | 1) PA gs) 15) | 3 | July 11 || 1 Sully. 23 ;-| 1 | Aug. 6] 2| Aug. 16 | 1| July 12 2| July 26 | 1} Aug. 7 De PAC eon 3| July 13 || 2'| July 28 | 4| Aug. 8 1} Aug. 18 2) July 14 2| July 30 | 2| Aug. 9 1| Aug. 20 2} July 165 || 5 | July 31 || 1} Aug. 10 2) Aug. 22 4) July 16 | Po eAug. Li 2 | Aug. 11 2) Aug. 27 1} July 17 || PAA INS Keee a | I weAti oa 13 1| Sept. 3 2| July 19 || 1| Aug. 3 | 5 | Aug. 14 | | 74 \ } 1 j The time and stage of the development when the codling moth larve become parasitized are not definitely known. Probably many larvee are parasitized after they leave the fruit and while in search of suitable places for the spinning of their cocoons. It is very evident that many larve are parasitized while still in the fruit. since adult 35215°—Bull. 115, pt 1—12——6 Ne PAO pe na = ee Pi 76 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. parasites have been obtained from codling moth larvee which were collected in windfallen fruit and confined in cages. At the time the parasitized codling moth larve leave the fruit they may readily be recognized by their inferior size and the absence of the pink color, which is characteristic of the full-grown codling moth larve. In the orchard on the grounds of the station, where numerous adult parasites had been liberated in the course of the season of 1911, fully 40 per cent of the band-record larvee were parasitized in the late fall. The average measurement of the head of full-grown codling moth larve is 1.5 mm.; the parasitized larva at the time of leaving the fruit has an average head measurement of only 1.3 mm. In the spring of 1911, 15 undersized larve, lacking the pink color, were confined in a separate cage; of these, 10 proved later to be parasitized, while the rest died from other causes. The parasite passes the winter in the larval stage within the host. The following spring feeding is terminated, and the host larva is completely devoured, except for the skin and the chitinous parts of the head. Within the cocoon of the host the parasite larva makes a small oval cocoon, white in color, within which it pupates shortly after. In 1911 one parasite pupated May 21 and issued as adult May 28, having remained 7 days in the pupal stage. So far as has been observed, only a single parasite develops in each host larva. The parasitized codling moth larve that winter do not modify the cocoon in the spring as does the normal larva, which provides an exit for the issuing moth. The parasite fly is therefore forced to gnaw its way out’through the walls of the cocoon. NEMATODE WORMS. On September 1, 1910, the writer collected a windfallen apple with a full-grown codling moth larva which was found to be infested with minute, white-colored nematode worms (species not determined). The entire body cavity of the larva was filled with the worms and quite a number of worms were also found in the burrows in the apple, where the mass of worms had the general appearance of mildew growth. . MISCELLANEOUS OBSERVATIONS. NUMBER OF LARVAL INSTARS AND MOLTS OF THE CODLING MOTH. The codling moth, like all arthropods possessing an exoskeleton, must shed the skin from time to time in the course of its growth. The process of casting the skin is called “‘molting’’ (ecdysis) and the stages between the molts are termed “‘instars.”’ The determination of the number of instars of the codling moth becomes difficult because of the small size of the larva in the early ley) (7 THE CODLING MOTH IN MICHIGAN. stages and its’ habit of feeding within the fruit, where it can not readily be located for observation without great care and labor. Mr. E. L. Jenne,! in his studies of the codling moth in the Ozarks, determined the number of molts of the larve by rearing them on small pieces of fruit in glass vials. The vials were frequently exam- ined for the cast skin of the head, and on this basis the number oi molts was established. Jenne encountered great difficulty in preventing the fruit from rotting and in maintaining the larve in a healthy condition. His records from 12 larve showed that 9 larvee passed through 7 instars and 3 larve passed through 8 instars. At Douglas, Mich., the writer, in determining the larval molts, made use of Dyar’s? method of head measurements, on the basis that ‘‘the widths of the head of the larva in its successive stages follow a regular geometrical progression.’ By this method the necessity of finding the cast skin was eliminated and the larve could be reared in entire fruit or in large pieces of fruit. On the other hand, this practice involved a considerable amount of labor and additional difficulties both in the finding of the larve and the taking of the measurements. TaBLE LXXIV.—/IJnstars of the codling moth larvx of the second brood, and head measure- ments in millimeters for each instar, Douglas, Mich., 1910. First instar. Second instar. Third instar. Fourth instar. Fifth instar. No. of ob- servation. . ; Hatch- First | Second Third Fourth ing. Mni. molt Min. Pale Mm. woh Min. rl Mm. jp Seer ee Aug. 11] 0.33] Aug. 15| 0.50| Aug. 22/ 0.66] Aug. 27] 1.00| Sept. 8 1.40 Dee ee Aug. 12 .33 | Aug. 16 .45 | Aug. 20 OO per COesen= 1.03 (8) ai | ae ae Seopa ae se a6 Wssuee S33) ees0 Oscaue .00 | Aug. 23 .63 | Sept. 5 1.00 | Sept. 1 1.30 GU cee ea ed Aug. 16 .33 | Aug. 21 .48 | Aug. 27 . 66 (3) .91 | Sept. 12 1. 20 Gages ee eC Os sa: 5O8 oc aGlonsase Hoo) | Alig. 25 xD (Caan eee ema (ee omg es 8 Sete ct Gate sae Se “20 Osea6s 8B) lg eaClOsc5se sD Ne SeO sauce . 70 CSN fl Pe ea SUE RA NE Gate ee Ucel Ra Tf otter a SOs aees vee leceOl@cbce . 46 Gye ties ech [pe 3 eat eel enc Spey Opal ee ese Seen ee pS Ob ea: 388) |e aOOssae5 .50 | Sept. 1 70 (2 hells oes eel Deira See allimeee oe Oe oes ee Aug. 20 .33 | Sept. 3 40 | Sept. 7 65 | Sept. 22 87 SD rosea AQe2 cso ae Ose yoo sept. .48 | Sept. 5 65 | Sept. 12 .83 | Sept. 21 1.06 Sixth instar. Pupation. ‘ Days duration of instars. No. of ob- pea One pbs Sixth | First | Second | Third | Fourth | Fifth | Sixth molt ; molt. instar. instar. instar. instar. instar. instar. {Neaeer ee eres Sept. 20 1.60 eh 4 7 5 12 12 2 SS seco Ss MS ee fods= clos seecc asses is 4 4 7 pecroocececlisococgaesscs Se | Sept. 18 | fe 538\) ws 4 7 4 5 17 << pice ee Sept. 22 1.50) Sep 5 6 9 7 10 g Lee Salo ee ae ae ee a= 5 AGP oases wan |vatinec 2 Seas Gee. i Ge et ee eR | Se a 5 ZA apo el LE pe er a Pees Be ee = Gi ee eee a ea ia Be ee eeer eaNNE ee aL ce a Seem eee SES = 5 i ee AR SR Sallie ne = et Rek tee hee gees eee eee a 14 4 TGS al epee eral 2 ence Oe ee eae Orbs ee a oy 12 4 a 9 (4) 1 Bul. 80, Part 1, Bur. Ent., U.S. Dept. Agr., 1909. 2 Psyche, vol. 5, p. 420. 3 Died. 4 Wintered. 78 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaBLeE LXXV.—Larval instars of the codling moth; head measurements in millimeters for each instar; duration of instars. Summary of Table LX XIV. | | a nts in mm. per - : | TERE ere ia Ber Days duration of instars. | ee es 5 - 5 poss : Observations. [skews ies s = 5 a H ees Poe 5 3 = & 2 i Z z = Ee, g 3a 2D = ss) om) eos § ceed Gee= ee eto) ce. ia q | & = S Tepe eee f= =) = = z = is] Gg 2 S = a ests ee ees a fp S a 3 = = = 3 er eae pe A = = S ) = 4 = DD eS | & | = wD = we a = = n | ae ea — Anveragel ss. <2 53: Se ee ee! 0.33 | 0.48 | 0.67 | 0.94 | 1.24/1.54) 63] 5.7) 7.9} 8.2] 13.0] @) Maxcmium sco 22222 aoe i S88 gh 73 | 1.03 | 1.40 | 1.60 | 14 ll 15 12 LZ (1) Minimum ess sas 32 40 GSE epsco. pe OGs el oOn iat = a 5 10 (4) | | 1 Winter. The head measurements were all made by an ocular micrometer of a compound microscope. It was necessary to bring the larve to a perfectly quiet position before the readings could be made. In 1910 this was accomplished by placing a cover glass over the larve during the early stages. The larger larve were held in place between two broken pieces of glass and by a small glass cover placed above. The results of these readings are given in Table LXNXIV. Four larve out of 10 reached maturity and entered their winter cocoons. Three of these passed-through six instars and one larva passed through five instars. A summary of these readings has been brought together in Table LXXY. The average length of the entire feeding period was evidently prolonged beyond that of the normal. The records for the minimum length of time of each instar represent more nearly the normal. In 1911 similar observations were again made for both first-brood and second-brood larve. To quiet the larve for the necessary read- ings they were held over a piece of ice under the microscope. The exposure of the larve to the ice was made as brief as possible and in most instances extended to a few seconds. It was found that the larvee would resume their normal activities within a minute after the exposure, and this treatment seemed to have no material effect upon the larve so far as altering the normal numbers of molts, since the results of these tests are identical with those of 1910. THE CODLING MOTH IN MICHIGAN. 79 Taste LXXVI.—Observations on the instars of the first-brood codling-moth larvex at Douglas, Mich., 1911. Date of hatching and molting, and larval head measurements in millimeters. Number First instar. Second instar. Third instar. Fourth instar. Fifth instar. of obser- vation. | | Hatched.| mm. By mm. eoeone mm. | ee | mm. | poe mm, | i Lata June 19 0.35 | June 26 0.46 | July 1 05667) July 5 | 0583} July. 9 1.10 DSi ees a ..do. .35 | June 27 Be WY BS oe oe 265)| Jiulys) 167] . 88 |...do. 1.30 Soe ee June 27 8 |p ditties 9S -o0 | July 6 .68 | July 11 -90 | July 16 1.18 rh Sool June 28 E358: do. 49 | dow). 700 Mulys 29" 21210 b July. 13 | 21550 Bat pe SdOn Sa eee al Rouen July 9 60 | July 11 .85 | July 17 ile 155 Gee ee AdO=s .30| July 4 46; July 8 65a ed One| So |s=2d0=.. tt5 ta Mess July 2 .35| July 6 .46| July 9 TOE | tise weet Be. Seer ctea July 12 1.30 Skee eee donee S035) |leeaGkOe a= 3405 pee Ome= 65 | July 24 .80 | Aug. 1 1.08 Cease mdOer. E815) een genes ie eeee July 11 62 | July 17 BOIM | n 2 ao. Silesia LOResee 30 June 7 .35 | July 10 46 | July 14 CRO) | = ec eal FS ae ea iN re oe (AE IE tLe eee res | ee apna oe oll eae Wh st July 15 70 | July 19 LOOM Sse is |e RR Me ee Me are | bie TS PSG ae July 14 65 | July 20 .89 | July 28 1.19 TIB32 seed Hie SR cs ar Bee a | eee ae | eae “dos 70 | July 18 THOSE | avs Ser ee eee eee jE oe Sse ae leis teal [are eh opel Pe ant eee (eR ce] ome July 14 1.00 | | Date of hatching and molting, and lar- val head measurements in milli- Days duration of instars. meters—Continued. 3 No: of observa- . a aire | on: Sixth instar. =a uae First | Second | Third | Fourth | Fifth Fifth Loft sixt instar instar. instar. instar. | instar. molt _ fruit. molt Te SS oe July 13 UTA) hl pane cae i ae 7 5 | 4 4 | 4 Usd Se Sas Bee ae ae = eee Aug. 2} Aug. 8 She eee fees c= se 3 1 30 See oe July 20 1.50 | July 27) Aug. 4 6 | 3 5 5 | 4 QR le Sa ee seers | de to ao July 23 | July 31 5 | 3 3 4 | 118 Ns Wes meer July 29 UA GUAT ON se al Att sel 2 alee Seek ye 2 6 | 12 O85 eS July 20 1.46 | July 27 | Aug. 4 6 | 4 3 6 | 3 Tears July 29 TRS Ue eA oe LOR ees = 4) Sis) eee eee ee ee lS 117 Sas kine Aug. 22 11.19 |! Aug. 30 11,29 4 | 3 te) 8 | 121 (NBT AE See rl bees SSE oe eel POP ee oe Saeed (eae Gare Le (Sau oseeee | CGY |i Se PS LEAS co Salle Satie Bet Neate ie Oe | (aye ee ee ear (ee ee 3 | Ae Sn Seis Sua Secs ate yee fie eee July 28 eS ielalys Sei: sete ee SEN as Ween eae | Al eng ee 1 dae ean nee aes Aug. 6 ThE ein 5 il | oe a (es ee | eee 6 8 9 1G ae eet ee July 25 1.50 | Aug JNO Se Oe | es tec sacente apc te A pecs Lm | nem re ea TA ioe Se July 19 Tee O Mail vamr od [uP AN Opel. |S eens Aree oe (ee eRe renee 5 | Days duration of instars—Continued. No. of : : observa- Sree astat- Remarks. tion. Total I “ite. : n co- ife. Feeding San Total pai Paces, | iene pers irs STi Ss See ks Ss Died in sixth instar. BS are See Pee ae A ieee (i eer ee) ee a Moth emerged Aug. 21; below average size. er oo 7 8 15 50 | Moth emerged Aug. 19; below average size. LE Ok tae Re Ee a |e ee ae eee 33 | Moth emerged Aug. 13; below average size. nie eos 7 7 14 45 | Moth emerged Aug. 25; average size. i Ai ies 7 8 15 37 | Moth emerged Aug. 16; below average size. Users OF | eee re ie oe SC IE See yet 2 Normal size; larvee wintered. Soe eal ee etn Ol ee. ee 59 | Deformed; died Sept. 9. Te Sh a IRE i ee er eee Deformed; died July 24. 1D. Ge ae aa ei AS a es ree es eee ae Died July 18. 1 ie ee Bra | Meer | we eer ae sie Died before pupation. i areca Caterer Me ee eee See Moth emerged Aug. 21; normal size. 1 cee tee 10 4 1 Fel ele as aa Se Died Aug. 20. 1 AS ae a 8 5 TS |e apace. | Moth emerged Aug. 12; normal size. | 1 Abnormal and not included in the summary. Seas ne pews Sere eT ee 80 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaBLeE LXXVII—\Larval instars of the codling moth; head measurements in millimeters for each instar; days duration of instars. Summary of Table LX X VI. Observations. Maximum...-- Head measurements in mm. per Kirst instar. Second instar. instar. Third instar. Fourth instar. 0.66 | 0.89 -70 | 1.08 -60 | .80 Fifth instar. Sixth instar. Virst instar. Second instar. Days duration of instars. | s Sixthinstar.| & = aS a a 3 > = a a gS | $ S > = = 2 = 5 = = fare i=. = S = Ze) = = o= 2 = 5 = = = S $s cia ec sil eel & = = = Si aS 4.1) 5.5] 61] 83] 64] 448 6 8 12 | 12 es 59 2 3 3 7 | 4 33 } I In the course of these studies there was a rather high percentage of mortality, but this was mainly due to the difficulty in properly remoy- ing the larvee from the fruit. TaBLE LXXVIII.—IJnstars of the codling moth larvx of the second brood; head measure- ments in millimeters; days duration of the instars; Douglas, Mich., 1911. _ | No. of | observa- | tions. Hatched. mm. 1 [ee ae eyede July 29 Vea eed tae doezes- Se eet eee dorii<: Lee re joe doseiss DP Seses ae | Aug. 2 | ee seer ae doss= ( eee 8 Rr } Aug. 6 Stes ese closes Oe ese edo ates 10a Aug. 7 Tee Ses Aug. 11 1 eae eee Aug. 12 Sick See ae see dole: 1 Bie eee aes ae dol Up ees 8 ae doz=- 16 tee os GOs: AV Rn eee Aug. 14 1 bee ee es ae do ==: 1 eee oe Aug. 15 | DO se eee oe Aug. 16 | 7A eee nee Aug. 18 | I eal ee dose A ee ee Aug. 24 A ee eee eae dows: Date of hatching and molting, and larval head measurements in millimeters. First instar. Second instar. Average 0.35 mm, | First | Second | molt Tee earls | | | | aie ot ap ae | Ate oe Aug. 3 | 45 | Aug. 7 PAGO sss ee -49 | Aug: 8 POs .54 | Aug. 6 Aug. 7 | .46 | Aug. 13 Aug. 8 | -46 | Aug. 15 Aug. 10 | ay Bel Ee a OO Le= o AG: Sek eee AREY IRE eee ee Aug. 20 | Aug. 20 | .50°| ; Aug. 17 | -46 | Aug. 25 s2d022253 .46 | Aug. 24 Aug. 28 | SOON Eee wee Aug. 26 -49 |. Aug. 28 Aug. 23 490 Se Ore Aug. 19 Sly sardou see Oe Beets ee ere: Aug. 25 .00 | Sept. 2 Aug. 28 DA Meet i Be Aug. 25 -46 | Sept. 2 Third instar. | Fourth instar. Fifth instar. | Third Fourth. m | molt. ee molt. oe } 0.75 | Aug. 11 OSE Ss ees 24°00) SAugs. 120) 122 0. ee eee Pia kota] oy een ee ae {2S ee ek eee (6 oe 3. oe a eee eee ee Te |e ee es erg Pr 1.22 66 | Aug. 27 | 11.08 | Sept. 2 ol (6n\5-2d0s5— 14.19 | Aug. 31 sa teas | 168) |o 2 toon | to es eee ee .67 | Sept. 1 Sse Bil Besa aees |------=- ir «te een en Eten ess 266) Sept. Welsaeee- | or ea je See iy i Bae eos eh [5228 Rew aren aie eee | oe tl ae eee Sept. 1} 1.19 siBT NCS couse ah eee Ben beess< == 260s]. 2.2 cet IE Se es ee : -80 | Sept. 15 | 1.08 Ques -81 | Sept. 18 | 1.08 | 1 Abnormal and not included in the summary. eee ? «> ie 81 THE CODLING MOTH IN MICHIGAN. TasLe LXXVIII.—Insiars of the codling moth larvx of the second brood; head measure- ments in millimeters; days duration of the instars; Douglas, Mich., 1911—Contd. | j , Date of hatching and molting, | and larval head measurements Days duration of instars. in millimeters—Continued. Noe of observa- - Se eA Cees Sas. Sixth instar. Same | Sixth instar. tion, | First Second) Third Fourth) Fifth Fifth | Left orn eo | instar. | instar. | instar. instar. Feed- | Winter- molt. | fruit. Ing] anes | | | 1 be eee ee ee eee eee bs ee es - 4 Gai] es ees onl is eee ee (oe Oe [ee hee DN Es oth lay es fle te | eee Te 5) 4 UG) raced rel (ens) fener y yeyaeel [oa he #3 SRS co Shel eee ales ae el (Ral Eee eee 5 Os eae eins [= ees ea me [Ey ee cee | Se arte Eis Sey Sl So rok (OR We eee eg on 5 oe ere Ns eee a ee A? se aie Sepa! hae Se cial bel ered ene ea ue s 5 Gee re a ee eee eee ee | ee Gee ee ees lake in| oe eh a 6 Te | et ee ene eae | ee ri ie iss | Neen | RHE S ye ee - Bi ins as, | ES en | a a fhe ele: oa eee Spee fl ee ES (EP ae peer eee a Aa Ee ieee [ec p eg en ayee Ret tet are a | ae Re Qasr Ae Aug. 26 | 1.81 | Aug. 31 Se | eee ee eS ee ee ee Ay Pe 8 5 (2) LD 2a ore Sor (RSX ee eal eee Sept. 18 = Speer ar Aue 7 6 (2) Seal] bees 1 ae UL oo ect ees, ok ia! hee as Sept. 10 Be) |S becoan Bese e nel eves 4 (yee eee [SN cea) Ro eee [ee ap eee = Ch (RE Ee ai Ciera F< as aoe Ka Pee WEE Tae, ery Yen [RiGee wene (fans [are Se ee ae = 5 | ge Sees eR EL Sayan WO re Fe N iS yeh laee 4 es ees Coates BL Sree g 5 | 7 Salas Shea |i oe |S a ee Pee ee as PRE [Er ieee ae Git ee Seite) Ce eae i el Uae eee! oem RR eI oS Loe eee ee eee eee gS 14 PA tec eg te ey Eek etn pn alte no ies ey Ge ke os (Roe Cae a=) 9 5 10) [ees ea ky, 8 See TEs eS ES oe ee cai (a eee a 5 (Ohh ae ge ee ng ee al ere = Neg Ne Se AQ re Foye Sept. 6 | 1.57 | Sept. 18 ap a Se seo eee ee) (een (mh er ee | 5 12 | @) ese Ser bade ee Sedeene |e ane ae F 9 | tS] 8 alente (ee cc [sa ee eres [ses een 5 IS gee | poe cee | bea | (oe ea LOR eRe eect a [at tne 8 ae aba eo ral Pdi ti eee POPE SIE Si care (See oa, a [eee gage 7 1 fee Ce eel ere eS ee Pee 7 ee Sen beot eno Oke 20s ae oe lee Se ce a [ees ae 7 12 25 G) Ee ee | Oct. 1 | 1.52 | etme e e|Ss —- He m10r lglg 1S le ee ae 1 Abnormal and not included in the summary. 2 Wintered. TaBLeE LX XIX.—Larval instars of the codling moth; head measurements in millimeters for each instar; duration of instars; summary of Table LX X VITTI. | Head measurements in mm. per Te Days duration of instars. - Observations. Kirst instar. Third instar. Fourth instar. Fifth Re Sixth instar. — Kirst instar. Second instar. Third instar. Fourth instar. Fifth instar. Sixth (feeding). Second instar. AW ETAL Hae = soe en 0.35 |-0:47 | 0.70-} 0.81 |-1.14 | 1.63 70\) GE 7 el 955 14.2 IM acini eee ee ee foe SSA Sole aol tt08) | 1 8 16s 29 10 10 | 13 23 MTA ae oe ee ee ee PAD Tes OO) a80) et s225 5 too AN 5 Asi 5 5 The records for the time of molting and the head measurements for . the separate instars for the first brood are given in Table LXXYVI. Of a total number of 14 larve, 8 attained full growth. Of these, 2 passed through five instars and 6 through six instars. A single larva (No. 8) that appeared stunted in its growth had seven instars, but failed to reach maturity. One full-grown larva of this brood wintered, while 7 resulted in moths the same year. Larve Nos. 11 to 14, inclusive, were left undisturbed during their early stages in order that their development should not be unduly delayed. 82 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. The observations on the molting habits of the second brood of larve (Table LX XVIID) were not all completed, as at times some of the larve were neglected on account of the stress of other work. TaBLE LX XX.—Head measurements of first-brood and second-brood codling moth larvx, - collected from banded trees at Douglas, Mich., 1911. a aS necond | Fuh || - | Seeond = roo roo + broo Joke brood Ne ee larve. any a larve. Ne a larve. | Ne 2 larve. * | eollected * | collected | * | collected |) * | eollected July 13. Sept. 17. | July 13. |, Sept. 17. | mm. mm mm mm. i |p abs 1 L578 16 AE G2Se al 16 1.783 2 | 1.509 2 | 1.626 17 | Picsszen | 17, plore 3 1.565 || 3 1.849 18 1.51¢ 18 1.7383 4 | 1.709 || OMT SO. | 19 | 1.809 19.| 1.62¢ 5 1.700 5 1.579 20 1.62¢ 20 1.739 6. 1.62¢ 6 1.849 21 1.5670 21 eS 1ie | AeSeO 7 | 1.689 22 | 1.629 22 | 1.783 18 1.299 8 1.62¢ 23 1.679 23 1.783 9. 1.629 9 1.789 24 1.62¢ 24 1.62¢ 10 1.7070 10 1.849 25 1.709 25 1.899 ata | 1.79¢ 11 1.68 ¢ 26 1.7028 26 1.789 12 1.562 12 1.68¢ 27 1.622 127 1.279 13°41) MEV? 13 | 1.689 28 | 1.629 28 | 1.673 14 1.56¢ 114 1.299 29 1.809 29 1.679 15 1.569 15 1.739 30 1.659 || 3 1.89¢ = 1 1} Parasitized larve. The results from these observations are, however, similar to those previously obtained. The pink color which is characteristic of the mature larva first appeared a few days after the final molt. A number of mature first and second brood larve collected in the field were measured for a comparison with those maturing in the laboratory. The records of Table LX XX show no material difference in the size of head of the larve of the two sets except that the field larvee are sheghtly larger, which is to be expected, since the latter have developed normally and without any interference. TaBLeE LX XXI.—The average widths of the head of the larva in its successive instars and the rate of increase at each molt; summary of Tables LX XIV-LX XIX. | : Average 1910, sec- | 1911, first | 1911, sec- increase Instars. ond brood. brood. ond brood. Average. at each molt. mm. mm. mm mm mm LINE AS Feat secs eck tig es RA eR EE SUN ile lee Sere 0. 33 0. 35 0.35 0. 34 0.13 TSLELOLON KG hapten el me ten er ye aL et .48 47 47 47 20 ARTE GE eee ld BU a: SP aes . 68 . 66 70 67 21 OUTER emcee ee eee ose oe eee eee ae . 94 . 89 81 88 30 | OT] Bg eet pS rae eta ak ah Cnet RA ote Sn 1. 24 1.16 1.14 1.18 37 SUE gH obese sleew fag Nas Ne saa 0S Re a Ne Sl ee > Se 1. 54 1.47 1. 63 1555) |: 22 sae THE CODLING MOTH IN MICHIGAN. | 83 The laboratory observations at Douglas, Mich., show that the num- ber of molts of the codling moth may vary even under uniform con- ditions. The great majority, however, have six larval instars, a few only five, and very exceptionally seven instars. Head measurements, when used in a series of consecutive tests, will bring out the number of molts of the larve, but this method can not be relied upon in determining the instars of any given larva, owing to the variability in size. The final averages as shown in Table LX XXI bring out the average widths of the head of the cod- ling moth larva in its successive instars and also the rate of increase of each molt. In 1881 Edwards * pomted out that the number of molts depends largely upon climatic conditions, these molts being more frequent in warm climates where the growth is rapid than in cold climates where the growth is retarded. ‘The present records on the number of molts of the codling moth in Michigan and in the Ozarks corroborate Edwards’s statement. Jenne found seven instars in the South, while in the North the writer found six instars. CANNIBALISM AMONG LARVZ OF THE CODLING MOTH. In confinement, when a large number of mature codling moth larvee are kept together, it sometimes happens that certain larve will attack and kill weaker ones and later devour them. After such a feast the cannibal larva assumes a dull, turbid color and can be readily recognized from the rest. It is evident that cannibalism among the larve also takes place under normal conditions. It has frequently been noted that a number of newly hatched larve have entered the same apple, but only a single or a few larve matured in the same fruit. Occasionally larve have been collected from bands which had the characteristic appearance of cannibal larve. CODLING MOTH LARVZX REMAINING TWO SEASONS IN THE LARVAL STAGE. An unusual observation on the duration of the larval stage of the codling moth was made in 1909 and 1910 by Mr. R. W. Braucher at Douglas, Mich. In the fall of 1908 a number of larvee were collected for rearing purposes and for studies to be made the following spring. Two of the larve failed to transform in 1909 and both were alive the following spring, 1910. On April 30 one larva had pupated; the other larva died June 24. The pupa, too, finally failed and was found dead July 18. Considering that the larva left the fruit about Sep- tember 1, 1908, or possibly much earlier, we find that one of the insects 1 Psyche, vol. 3, p. 159, ae 84 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. remained 20 months in the larval stage without taking food or water and that the other specimen remained 23 months in the cocoon as larva and pupa. The two larve had made their cocoons in a large glass vial. They came under the writer’s observation in 1910. The ability of an insect to remain dormant for a whole season and to transform subsequently the third season may possibly occur more frequently than has been actually observed. Such an adaptation would be of particular advantage to the species in surviving adverse seasons. CODLING MOTH LARVZ FEEDING ON APPLE FOLIAGE. To test the feeding habits of the codling moth larve on apple foliage three branches from which the fruit had been removed were bagged and on each 10 newly hatched larve were placed June 10. When examined July 20 it was found that in all three bags feeding had taken place, and particularly had the tender growths at the tips of the branches been eaten. In one of the bags, at the place where the same had been tied around the branch, one half-grown dead codling- moth larva was found ina cocoon. In one of the other bags one dead pupa was found, which was hardly two-thirds the average size. In the third bag no insect was found, though there was evidence of feed- ing. It may thus be suspected that in cases of total crop failures the insect can subsist on foliage in sufficient numbers for the perpetuation of the species. SUMMARY. The present account of the life history of the codling moth in Michigan is based upon a series of studies made in 1909, 1910, and Ouale In the course of a year the codling moth in Michigan pe one full brood and a partial second. In the field the earliest moths cf the spring breod commence to appear from 5 to 10 days after the apple blossoms drop, and the ear- liest larvee of the first brood hatch from 3 to 4 weeks after the petals drop. The earliest larvee of the second brood hatch from 10 to 11 weeks after the petals drop. During exceptionally warm and for- ward seasons the second-brood larve may appear considerably earlier, and were, in 1911, observed 8 weeks after the petals dropped. This record, however, should be considered very exceptional. The time of appearance and the periods of occurrence of the differ- ent stages of the codling moth are shown in figure 11, which, with the exception of the spring pupal stage, closely represents the seasonal progress under average conditions. Figure 20 similarly shows this progress in the development of the insect under prevailing warm and exceptionally forward seasonal conditions. THE CODLING MOTH IN MICHIGAN. 85 Kge deposition commenced in the cages from 3 to 9 days after the emergence of the moths, and most of the eggs were laid within 5 days after ege deposition commenced. In one instance eggs were laid 23 days after the emergence of the moth, but as a rule the great majority of the eges were laid within 8 days of the emergence. The number of eggs per female varied considerably in the cages— on an average, 57 eggs per female were obtained. A single female deposited 161 eggs. Under normal conditions in the field the average number of eggs is unquestionably higher and probably approaches 80 to 90 eggs per female. The average length of life of the moths was found to be 9 days for the males and 11 days for the females. Instances occurred when one male lived 32 days and a female lived 37 days. The length of the meubation period of the eggs varied greatly under different temperature conditions. For the first brood the av- erage length was7 days and for the second brood 8 days. The range of variation extended from 4 to 16 days. The effect of the temperature upon the length of the incubation period is shown by a plotted curve in figure 15. The length of the feeding period of the larve of the first brood varied from 17 to 45 days and averaged 25 days for the “ transform- ing” larve and 28 days for the “wintering” larve. Still larger variation in the length of feeding was observed in the second brood, ranging from 20 to 84 days and averaging 36 days. On an average the larve spun their cocoons and pupated in 7 days. This period varied, however, from 3 to 18 days. The pupal stage varied greatly under different temperature con- ditions, as is illustrated in figure 13. The average length of the pupal stage was 18 days and ranged from 1 week to 2 months. The length of the first generation, from the time of the appearance of the eggs to the time of emergence of the moths that resulted from the same, averaged 51 daysin 1910. During 1911 the duration of the life cycle varied from 29 to 87 days and averaged 50 days. The relative abundance of first-brood and second-brood larve varied from year to year. In 1909 the second-brood larve surpassed the first brood in numbers and constituted 57 per cent of the larvee for the season. During 1910, owing to the wide-felt scarcity of apples, the second brood only reached one-third the number of the first brood. During 1911 the second brood almost approached the first brood in abundance. Of the first-brood larve only a portion transformed the same season, while the other portion passed the winter in the larval stage. During the three years of observation the ratio between transforming and wintering larve of the first brood varied from 30: 70 per cent to Ye f 86 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 51:49 per cent, respectively, and averaged 36 per cent transforming larve and 64 per cent wintering larve. The larvee of either brood shed the skin (molted) five times, and had thus six ‘instars.’ A limited number of larve molted only four times. A hymenopterous fly, Ascogaster carpocapse Vier., was found to parasitize from 6 to 7 per cent of the larve of the codling moth. Hibernating codling-moth larvze succumb extensively to the cold during the winter. From 25 to 35 per cent were found to be killed. From the foregoing records of the life history of the codlng moth and from the variability of results obtained, it is evident that reliable data can only be obtained from a large number of observations. From the point of view of mechanical control of the codling moth the most important observations of the habits of the insect relate to the time of emergence of the moths in the separate broods. Such observations should preferably be made from carefully conducted band records. It is essential that the collecting of larve from the banded trees should commence sufficiently early in the season so that the first-appearing larva may be secured. It is also of importance to make the collections at regular and frequent intervals (three days) and for the entire season. Apple trees of late varieties should be selected whenever available. On applying the results of this investigation to the present methods of controlling the codling moth in Michigan it will be found that the poison-spray applications should be most effective when applied at the following periods: First—Shortly after the petals drop, to fill the open calyx cup and thus destroy the larvee which hatch later. It is the habit of most of the first-brood larve to penetrate the apple through the calyx end. Second.—From three to four weeks after the petals have dropped, when the first-brood larvee commence to hatch. Third.—Ten weeks after the petals have dropped, when under normal seasons the first larve of the second brood commence to ’ appear. During advanced seasons the above period may be short- ened to nine weeks and only very exceptionally to eight weeks, as noted in 1911. eee COPIES of this publication may be procured from the SUPERINTEND- ENT OF DOCUMENTS, Government Printing Office, Washington,:D. C., at 15 cents per copy. - Ma A Os U.S. D.A., B. E. Bul. 1155 Part Tf. D. F. J. I., November 4, 1912. PAPERS ON DECIDUOUS FRUIT INSECTS AND INSECTICIDES. THE ONE-SPRAY METHOD IN THE CONTROL OF THE CODLING MOTH AND THE PLUM CURCULIO. (Second Report.) By A. L. QuatntTance, Jn Charge of Deciduous Fruit Insect Investigations, and E. W. Scotr, Entomological Assistant. INTRODUCTION. The present paper constitutes the second report on the ‘one- spray’? method in the control of the codling moth in comparison with the usual demonstration treatment of from three to five appli- cations according to locality. The previous report on this subject will be found in Bulletin 80, Part VII (Revised), pages 113 to 146 (1911) of the Bureau of Entomology. The experiments herewith reported are in continuation of those detailed in the publication cited, and have been done in connection with other experimental work at several of the bureau’s field stations. In addition to the insect questions investigated in a given locality, attention has also been given to the control of certain diseases of the apple, this latter in cooperation with Mr. W. M. Scott, then of the Bureau of Plant Industry of this department. These tests have been made, as in the work previously reported, in widely separated States, repre- senting a considerable range in climatic and other conditions, and were carried out as closely as possible according to a uniform plan, for the most part by different members of the force engaged in Deciduous Fruit Insect Investigations. The experiments in Virginia in 1910 were carried out by Messrs. J. W. Roberts and Leslie Pierce of the Bureau of Plant Industry and Messrs J. F. Zimmer and J. B. Gill of the Bureau of Entomology. The work in Michigan during 1911 was under the immediate direction of Mr. E. W. Scott, and in Delaware was done by Messrs. W. B. Wood and F. L. Simanton of the Bureau of Entomology and Mr. W. B. Middleton of the Bureau of Plant Industry. Iy Kansas, in 1911, the work was carried out by Mr. J. B. Gill of the Bureau of Entomology and Mr. Leslie Pierce of the Bureau of Plant Industry. Since the appearance of the first report of the Bureau of Ento- mology on the one-spray method, additional information on the sub- 87 } i } i I ' ' 88 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. ject has been published by other workers, notably by Prof. W. E. Rumsey, in West Virginia Experiment Station Bulletin 127, and by Dr. E. P. Felt, in Circular 40 of the New York State Department of Agriculture and in the Journal of Economic Entomology for 1911 and for 1912. The information now available seems to warrant the conclusions given in the present paper. EXPERIMENTS IN VIRGINIA. The experiments in Virginia were carried out during the season of 1910 in the orchard of Mr. W. F. Gilkeson near Fishersville. The entire orchard consists of 30 acres, but only about three-fourths of this was used for the experiments, the remainder being sprayed by the owner. The experimental part comprised three plats, as shown NORTH RAKE KEK KK KOK AERC EX x > Koha Kock eo KK I CEN X N XX 2s XP EXD MOCEX bxldX BX x SS MEK REX OM KOC LRG Kad) EX x NS KaXOX Xa er eX EX CHG DEX x “8 MeO XIX a eG EEX x NX KK KOC OX KEK Oe. KO UX x \ BX ROK XOX eK XX IK x = NY HK TK Kon EK EEK T x ys N xk& KEK OCRIRT IOS aap CEE EEX x NS XX KKK Kae x x NN XX XX XX XXX XV ® x NY OPK “Xe HEXEN IR x X? KKK OX NR x S CONTINUATION OF APPLE ORCHARD -~ABOUT 15 ROWS. SOUTH Fig. 23.—Diagram showing arrangement of plats and trees in the W. F. Gilkeson eied: near Fishers- ville, Va. Trees counted are indicated by circles, the numbers agreeing with the numbers of trees in the tables. Variety, York Imperial. (Original.) in the accompanying diagram (fig. 23). The trees of each plat from which the fruit was counted throughout the season for records are designated in the diagram by the same numbers which these trees bear in the table. The orchard is on a hillside gradually sloping to the southeast. It had a good cover crop of June grasssand clover and was kept clean of dead limbs and rubbish, and the trees are headed rather low, thus facilitating spraying. The principal variety is York Imperial. There are a few Early Harvest trees scattered throughout the orchard, but none of these latter was included among the count trees. Plat I included 150 trees, Plat II 64 trees, and Plat III (the unsprayed plat) 10 trees, this last plat bemg in the center of the orchard. The treatments which the respective plats received are shown in Table I. ONE-SPRAY METHOD FOR CODLING MOTH, ETC. 89 TaBLe I.—Treatments and dates of applications for the codling moth and the plum curculio. One-spray method. Fishersville, Va., 1910. Plat I Plat II. | Plat II. : (One-spray method.) (Unsprayed.) | First application, Apr. 16-18 | Not drenched. Vermorel | Drenched with arsenate of | Unsprayed. (as soon as petals fell). nozzles. Mist spray. Ar- lead, 2 pounds to 50 gal- senate of lead,2 poundsto | lons commercial lime-sul- 50 gallons commercial phur (13-50). Bordeaux Dates of application. lime-sulphur (13-50). nozzles. Pressure, 200-225 Pressure, 200 pounds. pounds. Second application, May 16..-.|.-.-.-- GOs eee eee ane Commercial lime-sulphur Do. oniy (13-50). Not drenched. No arsenical. Third application, June 22--- ses2-- GO 28) Sst es as ee eo doweuct 32 528-2 ee Do. Plat I was sprayed thoroughly three times but was not drenched. Commercial lime-sulphur wash and arsenate of lead were used for each applicatom. Plat II (one-spray method) was thoroughly drenched, Bordeaux nozzles and high pressure being used. This plat received one application of arsenate of lead and commercial lime-sulphur and two subsequent applications of commercial lime- sulphur only. THE CODLING MOTH. In Table II is shown the total wormy fruit and fruit free from injury by the codling moth for the entire season for the eight count trees of each plat, the number of the trees in the figure agreeing with those in the table. TasLE I].—Number of sound and wormy apples for each tree from demonstration, one-s pray and unsprayed plats. Fisherville, Va., 1910. PLAT I. LIME-SULPHUR DEMONSTRATION. | | Total | Total | PeF Condition of | Tree | Tree | Tree | Tree | Tree | Tree | Tree | Tree | Tree | Tree a cent fruit. fe 7p one fo 5. 6. t- 8. 9. 10. 1 of | | Plat. | sound } fruit. Wonmny. —-=-- 141 29 47 80 35 27 31 72 22 12 496 ipa eee Sound:: >=: = 21,324 | 9,131 } 9,221 | 9,445 | 8,749 | 6,560 | 6,373 | 6,980 | 5, 622 | 2,566 85,971 |..._._- Total.....|21, 465 | 9,160 | 9, 268 | 9,525 | 8,784 | 6,587 | 6,404 | 7,052 | 5, 644 | 2,578 |86, 467 |._...-- Per cent sound.| 99.34 | 99.68 | 99.49 | 99.16 | 99.60 | 99.59 | 99.51 | 98.97 | 99.61 | 99.53 |_...__- 99, 42 PLAT Il. ONE-SPRAY METHOD. i [ | | Wormy.....--- 82 sg} 63 | 63 6 290) Sigs | 77 41 23 | BOS fete ae Sound..........| 7,282 | 6,543 | 8,044 | 7,539 | 2,023 3,372 3,7 | 5,87 3,065 | 35127 (50,645 |-=-<-=- Total..... 7,364 | 6,631 | 8, Le 7, 602 | 2,029 | 3,401 | 3,810 | 5,950 | 3,106 | 3,150 51,15 eee Per cent sound.) 98.88 98. 67 99.2 99.17 | 99.7 99.14 .13 | 98.70 | 99.68 | 99) 27 eae | 99.01 | | | PLAT Ill. UNSPRAYED WOEMY 522= 5. 5- 781 423 487 480 300 296 812 188 421 776 | 5,019 | eee Sound..........| 5,159 | 1,908 | 3,067 | 2,935 | 1,874 1,329 | 4,413 | 1, 168 | 2,285 3, 227 127, 365 (ee = Total. .... 5,940 | 2,331 | 3,554 | 3,415 | 2,229 | 1, 625 | 5,225 | 1,356 | 2,706 | 4,003 |32,384 | ee Per cent sound. + 86.85 | 81.84 | 86.29 85. 94 | 84.07 | 81.78 | 84. 45 . 61 | Seeeeee | 84.50 86.13 | 84.44 90 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. ~Plat I, which received all three applications of arsenate of lead, gave 99.42 per cent fruit free from codling-moth injury, the per- centage for individual trees ranging from 98.97 to 99.68. The total number of apples counted from this plat was 86,467. Plat II received the one-spray treatment and shows a total of 99.01 per cent of fruit free from codling-moth injury, the percentages for individual trees ranging from 98.67 to 99.70, and the total number of apples examined being 51,150. This shows a difference of only 0.41 per cent in favor of the demonstration. Plat III, the unsprayed plat, shows 84.50 per cent fruit free from codling-moth injury, the total number of apples examined being 32,384. This shows a gain in sound fruit by the demonstration treatment of 14.92 per cent, and by. the one- spray method a gain of 14.51. As will be noted, the percentages of sound fruit from the check trees is rather high. This is probably very largely due to the fact that these were located in the center of the orchard, all the surrounding trees being sprayed. In Table III are shown the places of entrance into the apple of the total larve for the season for each tree of each plat, and also the percentage, by plats, entering the fruit at the calyx, side, and stem. There was a total of 496 larvee on the demonstration plat, as against 505 larvee on the one-spray plat, a difference of only 9 larvee in favor of the demonstration plat. On the unsprayed plat there was a total of 5,019 larve. Comparing the percentages of larve entering at the calyx end of the apple on the different plats it will be noted that the demonstration plat shows 33.06 per cent entering at the calyx end as compared with 13.46 per cent on the one-spray plat. The unsprayed plat shows 63.86 per cent of larve entering at this point, which may be taken to indicate the normal behavior of the larvee. Table IV shows the comparative efficiency of the demonstration and one-spray treatments in preventing infestation at calyx, side, and stem. By comparing the figures for the different plats it will be seen that the one-spray treatment was more effective than the demonstration in preventing entrance at the calyx, and less effective in preventing entrance at the side and stem. The demonstration treatment saved a total of only 0.41 per cent more of the crop than the one-spray method, most of this saving being due to prevention of side entrances. ONE-SPRAY METHOD FOR CODLING MOTH, ETC. om Tasie III.—Places of entrance of fruit by total larvx of the codling moth for each tree of Fishersville, Va., 1910. Total nuinber of larvee and place of entrance of fruit for each tree, first and second Place of entrance. | Tree ale First and second broods: First and second each plat. PLAT I. LIME-SULPHUR DEMONSTRATION. broods combined. eug age of | | larvee | Total | | Total) enter- | num- | for | ing at | ber of Tree | Tree | Tree | Tree | Tree | Tree | Tree | Tree | Tree |plats.| calyx, | larvee. 2: 3: aa en 5: 6. te 8. Quail Om side, and stem. Bi Tes he | ial a al) Gale se Ae) 3516402233406: eee 20 26 40 22 12 11 14 12 | 9 |. 226 | - 45: 57 oseege. 3 7 15 8 5 4 26 6 0 LOG HPA 23 7s hee 29 47 80 35 27 31 72 22 | 12 496 | 100.00 496 | PLAT II. ONE-SPRAY METHOD. ] | i eeOM Te eae. 12) 11 4a a niggling eG: ene 49 42 30 4 14 17 40 | 26 13 2805|5 =< 5Ds4 55 asaseae 28 15 26 1 11 f | 20) ear telen 6 NOY BIRO Ne ooaoee 88 63 63 | 6 29 | 33 77 | 41 23 |; 505} 100.00 505 | | PLAT III. UNSPRAYED. | | | | 252 | 297| 296] 244| 196] 561] 111) 251) 510 (3,205 | 63.86 sees 78 88 | 100 60 58 93 43 62; 105; 819 165323 eee 93; 102; 84 51 42 158 34 108 | 161 | 995 19582) eee coe — ——~-||——- | | ——| ——— 355 | 296 | 812] 188; 421] 776 5,019 100.00 TaBLE IV.—Efficiency of the demonstration and one-spray treatments as shown by the percentage of wormy apples. Plat No. I. Demonstration OM@lS prayers se cine oo Sse sled e- (UmSprayedse nat amiann ahiccco ee Lo III. punctures.’’ Fishersville, Va., 1910. Percentage of wormy apples. Calyx. Side. 0.19 0. 26 518} .54 9.89 2.53 Total Total pun ber number co) wormy | Stem. Total. apples. apples. 0.12 0.57 496 86, 467 qoL . 98 505 51, 150 3.07 15. 49 5, 019 32, 384 THE PLUM CURCULIO. Table V shows the effect of the treatments in the W. F. Gilkeson orchard in controlling the plum curculio on the three plats. and feeding punctures are combined in the table under ‘“ Number of 59743°—Bull. 115, pt 2—12——2 Keg 92 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaBLE V.—Injury by the plum curculio for entire season. Plats I, II, and III. Fishers- ville, Va., 1910. PLAT I. LIME-SULPHUR DEMONSTRATION. Number of punctured and sound apples, etc., per tree in each plat. Total per cent of Total | of fruit Tree | Tree | Tree | Tree | Tree | Tree | Tree | Tree | Tree | Tree for free il: 2. 3. : De 6. Ue 8. 9. 10. plat. | from injury Number punctures... .. 1,333) 677) © 618) 747) 864) 757) 885) 819) = 369) 210) 7, 229). 2-2 ee Number fruit punc- GuULed ese ee es 987) 321-397 TAT 5221) 483) 476, 542! 21239) 123 4 belle eee Number sound fruit... ./20, 478) 8,839) 8,871) 9,054) 8,262) 6,104) 5,928) 6,510) 5,405) 2,455) 81,906)........ INtimibertrulteecse. seen = 21,465) 9,160) 9,268) 9,525) 8,784] 6,587] 6,404) 7,052) 5,644) 2,578) 86,467).....--- Per cent free from in- JUBYsas- sete eee 95. 40) 96. 49] 95.71) 95.05) 94.05} 92.66} 92.56] 92.31} 95.76) 95.22).......- 94,72 PLAT Il. ONE-SPRAY METHOD. Number punctures. .--. 855) 1,025) 563) 744, 113) 271) 231) 314, 149} 223) 4,488/........ Number fruit punc- CUTCOS cet sees 428) 584) 544 516) 107; 156; 143) 202 OO) 2 2 882e once Number sound fruit... .| 6,936) 6,140) 7,563) 7,086) 1,918) 3,245) 3,667| 5,748] 3,015) 3,037) 48,355)......-- Number fruit-.-..-.--- 7,364] 6,724) 8,107) 7,602) 2,025) 3,401} 3,810) 5,950) 3,105) 3,149) 51,237).......- Per cent free from in- JULY Secrest ae Sees 94.20) 91.31) 93.28) 93.21) 94.71) 95.41) 96.24) 96.60) 97.10} 96. 44)......-. 94. 37 PLAT III. UNSPRAYED. Number punctures. - -.. 917, 311) 332) 483) 231; 168 683 146] 342) 620) 4,233/........ Number fruit punc- : CURE Sea nee 673 246 297 344 165 128 463 81 283 434 3) 114 oe eoe: Number sound fruit....| 5,267] 2,085] 3,257] 3,071| 2,064] 1,497] 4,762] 1,275] 2,423] 3,569] 29,270|........ Number fruit...02. 0.1) 5,940) 2,331) 3,554] 3,415] 2,229] 1,625) 5,225] 1,356] 2,706] 4,003) 32,384|........ Per cent free from in- JURY one ee Ree: 88.67} 89.44) 91.64) 89.92) 92.59) 92.12) 91.13] 94.02} 89.54) 89.15)........ 90. 38 On the demonstration plat the percentage of fruit uninjured by the curculio was 94.72, and on the one-spray plat 94.37, which shows only 0.35 per cent in favor of the demonstration plat. The unsprayed plat shows 90.38 per cent free from curculio injury. As has been noted, the check trees were in the center of the orchard and sur- rounded by sprayed trees, which no doubt accounts largely for the high percentage of sound fruit on the check plat. EXPERIMENTS IN MICHIGAN. The experiments in Michigan during the season of 1911 were carried out in Mr. Edward Hutchins’s orchard near Fennville, Mich. The entire orchard, consisting of 205 trees, was used for the experimental and demonstration spraying, the experimental part being located in the western portion of the orchard where the principal varieties are Baldwin and Rhode Island Greening. The plats were laid off across these varieties in order to have both represented in each plat. (See fig. 24.) The east side of the orchard is composed of a general mix- ture of many varieties. ‘Trees of each plat from which the fruit was ONE-SPRAY METHOD FOR CODLING MOTH, ETC. 93 counted throughout the season for records are designated by the same numbers which these trees bear in the tables. The orchard is almost level, sloping slightly toward the west. It was kept clean, cultivated throughout the summer, and sown to oats in the fall for cover crop. The trees are 30 years old and medium to large in size. Plat I included 18 trees; Plat II, 17 trees; Plat III, 19 trees; Plat IV, 12 trees; Plat V (the unsprayed plat), 21 trees, this last plat extending across the orchard near the center. The treatments given and dates of application are shown in Table VI. YOUNG APPLE ORCHARD. af AeA Sel ath ae = HAY FIELD. On vuUxaxnononNnsAHeE AE OnO 1G cloth Ox =. 0 HUA WOODOWIOOD RHAQMVOAwATMNHA Aa ~* - (e) A YW) + YOUNG APPLE ORCHARD. wn + fe) FLAT 1a W. WD GJ Gao DD WJ G K S K S K S K GK FQ Cle ©® G G GO MRaAaQOZzox~ oc VUTUHaO CMU) NIE - July 23 21 180 | Aug. 17 | Sept. 3 17 i2y es sdos doses. 21 181 Qeces dors 17 128 July SY eee 20 182 dos:<: dora 17 Summarizing the above records we find the earliest pupa on June 25 and the latest August 17. The first adult emerged on July 13 and the last September 3. The shortest pupal period was 13 days, the longest 31, and the average 19.84 days. No record with regard to the sex of larve or adults was taken. Table IV shows the length of the pupal stage summarized. CODLING MOTH IN SANTA CLARA VALLEY. 117 TasLe 1V.—Pupex of the first brood. Variations in the pupal period. Summary of Table ITI. Number Number Number x Number | of pupe. DAYS illo pupe. Bays lot pupe. Days. ol pupe. | LESS: iI 13 31 19 4 24 1 29 1 14 39 20 3 20 gril eee eae 30 3 15 35 77 As |e cee ape 26 1 31 2 16 13 22 ital eee oe 27 8 7 6 Pea ji | eles 5a 28 182 34 18 1 FIRST BROOD OF MOTHS. Time of emergence—Larve and pup were collected from under bands on apple trees on June 21, June 28, July 6, and thereafter twice a week until September 20, when the last collection was made. Figure 27 shows graphically the adult emergence of the first-brood moths from this material and figure 28 the percentage which passed eae tl en Hl a ee a es a it a fe oe Hae it In anit 6 cae ah aaa ait : rs : Hee in aa 1H a ‘cc Ta it il ete Benes HN NAN ret Hl Fe (TENA tint I Ht cht TT JE ai Av ANU August September === SAX JERE RE Ayrep abeuany Fic. 27.—Diagram showing emergence of moths, derived from band-record material collected in 1909. (Original. ) the winter in the larval stage. They also record the daily emergence of these moths from July 12, 1909, to June 9, 1910. Table V shows the adult emergence for the total number of moths of the first brood, including both those from the general band record and those from the individual pupation records. 118 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaBLE V.— Moths of the first brood; total emergence. | | | Number | : Number ; Number | Number Date. | emerged. | Date. |emerged.|| Pate- |emergea.|| Date | emerged. July 12 55 July 31 124 Aug. 19 48 Sept. 8 2 July 13 111 Aug. 1 130 Aug. 20 68 Sept. 9 8 July 14 27 Aug. 2 199 Aug. 21 38 Sept. 1 a July 15 101 Aug. 3 168 Aug. 22 27 Sept. 11 8 July 16 68 Aug. 4 130 Aug. 23 30 Sept. 12 13 July 17 60 Aug. 5 144 Aug. 24 45 Sept. 14 28 July 18 28 Aug. 6 101 Aug. 25 34 Sept. 15 78 July 19 56 Aug. 7 76 Aug. 26 29 Sept. 16 14 July 20 65 Aug. 8 96 Aug. 27 22 Sept. 17 10 July 21 107 Aug. 9 148 Aug. 28 25 Sept. 18 ie July 22 87 Aug. 10 114 Aug. 29 12 Sept. 20 3 July 23 183 Aug. 11 87 Aug. 30 4 Sept. 23 1 July 24 105 Mnf 1 108 Aug. 31 5 Sept. 25 2 July 25 32 Aug. 13 74 Sept. 1 8 Sept. 26 2 July 26 41 Aug. 14 106 Sept. 2 9 July 27 25 Aug. 15 119 Sept. 3 6 4,359 July 28 Aug. 16 92 Sept. 4 2 July 29 101 Aug. 17 134 Sept. 5 15 July 30 | 160 || Aug. 18 103 Sept. 7 8 sererisriisct?' a e i | i ULL HII ees secemmetneete ee TTT th ttn eee TTT nl a NAAT LS THT bp tt i fill i Hat iH S UaRTaTEi| PriMERARETien HLT NEUEN ST Ly UTA nA TACT eA EE ! il ce - Ith Wi LH a THe tit at it HUMAN | tT INIA Hhratt UUVANANETA a fe [ af |] IM weil wal IVLNUIAL AU LATA : ; a LUUATTATAEAAATAHT AM HN i NAMATH i ITLL mt CE IA LTTE * April =, © p abeuaay — om. Mre 7 pleyuauye 4 — aunyeuadwie, i o Number of Moths Fig. 28.—Diagram showing emergence of moths, gest ved from band-record material collected in 1909. (Original.) It is therefore apparent that maximum emergence took place dur- ing the period of from July 13 to August 18, and that thereafter the emergence was drawn out all through the balance of August and up to September 26. SECOND GENERATION. SECOND BROOD OF EGGS. No further observations on the life history of the codling moth were taken in 1909. CODLING MOTH IN SANTA CLARA VALLEY. 119 SEASONAL-HISTORY STUDIES OF 1910. SPRING BROOD OF PUPZX. Time of pupation.—The earliest pupation observed during the spring of 1910 in the breeding jars was on March 3 and the latest pupation April 25. Considering the time when the first adult emerged on March 30, and adding the average length of the pupal stage, or 40.7 days, the earliest pupation must have taken place about February 18. As the latest adult of the spring brood of moths emerged on June 9, the last overwintering larvee must have pupated about May 1. Pupz were therefore in evidence from February 18 to June 9, a period of 111 days. Figure 29 shows when the first, last, and maximum pupation took place in the rearing cages, as well as the daily mean temperature, and HH a Ll | “ | fe cn ieee REE ae My if 22 il ~ No I a od &. it | tt i HIN aL ek UE TEA AE A HERE ei i Qo +. oi) jloyuea eae Mep abeusay (os i=} ee ina ONE na th Mi Hen QUANTA “ACN nN il vis uN NAM fil Fic. 29.—Diagram showing time of pupation of spring brood of pups, 1910. (Original) == | N Mae ane 26 A pril that the overwintering larve pupated from March 3 until April 25. Most of the larvee pupated during the period from March 8 to 25. An examination of figure 29 shows that the sudden increase in daily mean temperature after February 20 probably started overwintering larve pupating. The high daily mean temperature from March 8 to 20 explains the maximum time of pupation, and shows that a drop or increase of 5 degrees in mean temperature usually influenced accordingly the number of larve pupating. The period of low mean temperature from March 20 to 27 stopped pupation to some extent, but it was started again in the remaining days of March and in early April. By this time practically all of the larvee had pupated, and the warm period following has no bearing on the time of pupation. 120 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. Length of spring pupal stage-—Records were obtained on 229 pupe which were kept in vials under natural conditions (see Table VI): TaBLE VI.—Spring brood of pupx. Length of the pupal period for overwintering larve collected during 1909 on banded trees. Date of— Date of— No. of | Sex Sex | Length|| No. of | Sex Sex | Length indi- of of jofpupal|} indi- | of of jofpupal vidual. |larva.| Pupa- Emer- |moth.| stage. || vidual./larva.| Pupa- Emer- /{moth.} stage. tion. gence. tion. gence. Days. Days 1 é Mars coueAprelG roi 44 Alls) Re a eee Mars sisi Areg24atse te 42 Dialer Mle=s Orcs =sdOlee oS 44 U2 \Bsaee 4 ae doves Base pes Bo 42 3 Ge Jee OO Rese a| se do. roi 44 (6) Beeeee ee dow OO ees) ene 42 4 OW eee Goes. Apr. 18 2 46 (25 Baoan Bee Gove eri dot eee 42 Dial besee ar Mars, 40 MAipraek Oni se se 46 79 BY WEERGORascal sore 2S oS 43 Guile suena Mars oll Maven Oni argy | 34 76 e) =dose- does Q 43 7 3 Mar. 6) Apr. 19 So all 44 || 77 rot adore Apr. 23 roe 44 Sei Op speedos. Apr. 20 Qo | 45 Us| eeeeel eee does? PADS |H5_2 41 Sh 3e (0 Ko eee Apr. 22-5) || 47 || 79 Q =xdOz= Apr. 23 Q 41 LOM es doe Sos Sarl 47 80 Q ee dOss5. 4) 2Apree25 Q 43 il Q IIE Yrs 27 ee Oe ce] Q 46 || Coal) ees fee does PCO Li ee meee 43 4G (eine ene Mar. wdaunes peers. 45 82s Tic |e ce sens oor ae 43 TS yh aoeeee == 002 aL Osos se | ere 45 83 Q |...do sedors Q 43 ig, Sh pe een doz EROS RE stay 45 84 o |Mar. 14 | Apr. 24 Jo 41 1D) ane ..do. May Quire. 31 85 Q ado doz Q 41 HOSEA Ee ced O.e= ApEn aes | 44 86 3 dor doe Be 41 17.) ¢@ |Mar: 9 | Apr. 22; ¢ | 44 Sy | Bere ban Cees (MA Eb Da; yk BEANS Pe 41 Shae ..do. IN Sees 49 8Sojeeeeecl= HdOr53 5) PAprar2so [pee ee 40. 19} 9Q ..do. ADE 225 aa 44 Sone eae SAGO 5551 SG OSS eae 40 20) scGMesce Apr. 23 |. o 45 90 Q 20022525) Alprs 929 Q 42 21 Q ..do.. =O Q 45 91 Q Ed Oee es Apr. 24] Q 41 22 Q S50 (55 Apr. 22 Q 44 92 Ss dor. 2 Apr. 27 fo 44 PBS seceel oc do.. SRC OSES EE ee 44 93 Q EC OS es ep Ee 4 Q 41 24 2 exdoze Apr. 23 Q 45 94 Qo PEG Ona Prag 2o Q 42 D5 ere al eee do.. REG (pAb teed (RSE eis 45 | Oot Reea te dow Goa) eA praise eee 41 26 oo Ore S20 022 Jo 45 OG) | Sasa Obes SAO ses rut eee 41 27 2 Mar. 10 | Apr. 24 Q 45 97 ea ESdOze. SEGO2 9220 uave 41 28 Pe eae Suess sel!) ZNjorrs 97-8) ly shee 44 98 2 eLdoti ea Apr. 25 Q 42 29 Q LzdOe LeGbene || 44 | OOM EE Hees 5 [ee dot e= Apr azou|eeeeee 40 30 o ..do. Owese= |) os 44 100 Jo = Be Xo (oes ADE ReZ4G FINNS | 44 2 ae es oe eudOeeene Apres 257 |B ece 40 ayaa Baas 2-002: ADT 2 Les ee 41 122 rei “Cd OS=8 3 BEKO C0 ees fof 40 eh eee OSs ln Oss. o| eee 41 1230 eee 230 O222%2 AGG ptess 40 Oia eaeee Adotsc24| Apr 23 liege 43 124 é Edo te Apr. 27 rol 42 BS On kde. sar Aipr--24 | 0 44 |" Eo ee tdeta. Kp 40 AGT | Rieric]e| eee dose ING) Fs ZB) ee aes 43 126 Jo Mar. 17} Apr. 28; ¢ 42 Oihlkeeecaee Gol PAprs 24 ees ee 44 P20 dower ApPre2o fs: 39 58 Q dose e-Oeoeea|) © 44 TERI Ee Sn dasseey APE. 27 Ps 41 59 | @ S3d022222| “Apre 23 Q 43 E29 aie Ae Bs dona. APES Zon |se sees 39 it tea Pree do. Ges aus besece 43 130} Q = 60s 56 May 2 Q 46 GItives doz | Apr. 24 3 44 | 131 Shalit Re Oks Bae Apr. 29 o 43 62 Jo Mar. 12 | Apr. 23 J 42 eye Pet Be SedOLztsc Apr n28hle ssa 42 Odie sae eee doves s|s 2d Of eee ae 42 ESS ate Cuma Owen Apr. 29} @ 43 64 BAGO A Be) H eG 0) Rar 2%! Q 43 134 a Je (oer Apr. 27 rot 41 65 § SA (oer | Sao i4| ee ae 43 1S) Beeass Boe GOse-- Apr 305 see—— 40 66 ref NdOe=555 52800: ret 43 U6.) seme shee does ce £00s2.-2 kee 44 ye | Ee Mar. 13 |...do. oo 42 1S Y Os fete eee Le dol ies Apr. 28: |Es- Se" 42 68 | dos =5)=2-d02 Op 42 138 8 G05 5 3c Apr. 29 § 43 69| 9 doueaes do 6) 42 139,| © | Mar. 18 |...do..... 42 (AUR Pees = Blac GO. SS HPAIDE a20) ||Peeeee 43 | AOR eee ere? poe Apre-27. [Sassen 40 ! — =. .--” - ——_ CODLING MOTH IN SANTA CLARA VALLEY. At TABLE VI.—S pring brood of pupx. Length of the pupal salle for overwintering larvx collected during 1909 on banded trees—Continued. Date of— | Date of— No. of} Sex Sex |Length|| No. of | Sex Sex | Length] indi- | of of jofpupal|} indi- | of of jof pupal vidual. |larva.| Pupa- Emer- |moth.} stage. |] vidual.|larva.| Pupa- Emer- |moth.} stage. tion. gence. tion. gence. Days. Days 141 Q Mar. 18 | Apr. 29 42 I'S Gy see Ware 127. | Miaiyine 4: ||2 a= 38 1D |e ncaoclleue dow GOneere|e caus 42 | 17a) Ge|) Marss29 Goeesee é 36 1283 Heo eee doess- LDR, ASN seosne 41 | AS Se eee | ane doseee WEN? BY eo oeSe 37 144} Q CO castllocnO Oeesae Q 41 189} Q | Mar. 30| May 6]! Q 37 145 rot CWecadallos-G se rot 41 | 190 Q Goer May 5 Q 36 4 Ge ears: dows INO ZB |lenecoe 38 | ES eee Maresle | MaveenG sheer. 36 WA Teco. 5: dozs-=- Mie. .gbileesees 47 | 192| @ doses: May 7 Q 37 148 o doles Apr. 28 & 41 193 roe dow May 6 So 36 149 10) dOssse- May 2 ° 45 194 | Q dozeee- May 8 Q 38 150| oS Goma | Aprar29) eg 42 195 Q Apr. 1| May 7 Q 36 151 Q Gowen: May 2]; 9 45 196 Q Apr. 2|May 9 Q 37 152 ree Gossee Apr. 28| ¢ 41 | 197 o domes: May 7 3b 35 153 ree dosss- Apr. 30| ¢ 43 | 198 Jo doles May 9 o 37 1545 | eee Gasol WETS}. keeace 46 | NOD Noweetielicce Goseene Maivanrie ae 35 155 Q Mara 93 | peedosse=- Q 45 200 Q aa Osea May 9 Q 37 156 12) ONena bend Oenne< Q 45 201 Q TAD ES el sae Osea Q 36 157 12) Mar20)|s250052-.- Q 44 202 a Oss eee May 10 3 37 INS ia seciSe GOS=222|s=- 00 Meese | 44 203) |e POR ZEW he) Oy eae 32 159 ref anes ese May 2/ ¢ | 43 204 ref Apr. 5| May 9 rei 34 160 | 9Q dome-- May 3 Q 44 205 | @ Pedomere May 10 Q 35 161 Q doses | sa dokes Q 44 206| Q BAO (eee May 8 Q 30 G2 eee ee doe Jy ne 748) eee 40 207 Qe Apr. 6] May 10 Q 34 163 Q doze May 3 Q 44 AVS | ssboe- INGO Rs Mtoe saC Onan a Eee eas 32 164 3 doz May 2 rea 43 209 ea dos=== doe ree 32 165 roe Gore Apr. 30 41 PAD See ctooe dose Wey TI eee oe 33 GGG eee OWL dee ERC OE see: 41 211 Q doa May 10 Q 32 167 | o | Mar. 21 5635 54- fof 40 | 212 Q Apr. 9] May 13 Q 34 168 ref dows May 4 rch 44 213 rch Apr. 11 | May 14 ee 33 169| ¢ doi ac 9.14 0) cats 10 are 40 || 214; 9Q doe May 13] 9Q 32 170} gS | Mar. 22} Apr. 29} ¢ Soe a lon ao dows May 14} Q 33 ITZ ee ar oe dowree Matyi eur 2BVe le ONG | besee dow: Withy Alb ie oeese 30 UCP || sees Oss. AT 245056 Ae 2h Q dowe=- May 14 Q 33 173 So domes Apr. 29 3 B8ael|l me 22l8 Qo doses May 12 Q 32 174 ie) Mar. 23 | May 3 Q AN TORE ae Apr. 12 dos o 30 (Onley Orie Mar 25 qleApre 30) |) 2 36 220| Q | Apr. 13 | May 15 Q 32 176 2 do: May 15 i) 51 22 lea ee OO basse Maye sean 30 Nidan eee |e dos2= IGA aria Zab Eee nae 38 222 3 7M Or dee eS eC hcase ea 29 178} 9Q Pad Os s2.5 May 6] 9 42 || 223 Q | Apr. 18 | May 17 Q 29 7 | ee | ee dose WEN Gi lee sobs 40 | 27 AG | eee Sad Ouse SDE Ques | eterno 29 ASOsSo tes leas do2: Noes Gl eee S6unliin moe lee near pr 20s | uiia ye 20) |e ee 30 181| 2 | Mar. 26|May 4] 9 SOMa e226 ON Adon PG ingaae Q 30 182 ° Gore: Apr. 30 2) SH) i 12 BRUTE tees ADT 24 | Mayer 24 eee ee 30 183 Q dOnea2= May 3 é 39 | 228 Q ed OFSaa= May 25 Q 31 184 2 SO Orso May 2 37 | 2295 ao Apr. 25] May 24) ¢ 29 185} © dais May 3| 9 38 | The variations in the length of the pupal periods, as shown in Table VI, extended from 29 to 61 days. - Taste VII.—Spring brood of pupx. Variations in the length of the pupal period for 229 pupex as recorded in Table VI. Number : Number Number - Number athe of pupe. Days. |! of pupe. Days lat pup Days.” |) of pupe. Days. 4 29 4 35 28 41 3 47 6 30 8 36 28 42 1 49 2 31 8 37 28 43 1 51 7 32 8 38 34 44 i 61 5 33 4 39 18 45 4 34 | 22 40 5 46 An examination of Table VI shows that larve pupating in March usually required several days longer for the pupal periods than larve pupating in April. 122 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. Table VIII shows the summary of observations recorded in Table VI and that the average length of the pupal period was 40.7 days for the 229 pupe. TABLE VIII.—Spring brood of pupe. Summary of pupal periods of Table VI. Observations. | Days. | Maximum....... 61 Minimume=s-22- 22 29 IASC. Cane 40.7 Comparative length of pupal periods of male and female larve.— An attempt was made to ascertain the sex of the future moth while in the larval state, by the occurrence of two black spots on the dorsum of one of the posterior abdominal segments, the presence of which indicated a male. Records were kept on each individual that could be observed well in its cocoon, and in each instance the moth issued true to the sex ascribed to it while in the larval state. In comparing the total pupal periods for 64 males and 87 females, the average length of the pupal stage for males was found to be 40.5 days and that of the female to be 40.6 days. This difference was not sufficient to warrant any conclusion during the 1910 season as to the respective lengths of the pupal periods of the males in com- parison with that of the females. Temperature conditions.—The temperature conditions influencing the pupal periods of the spring brood of pupe are summarized in Table IX: TaBLeE 1X.—Spring brood of pupe. Temperature conditions influencing the pupal period. Departure Maximum. | Minimum. Mean. rom normal. | IE Son a. ny iMarchite- eee 66. 2 44.5 55.4 +1.7 Acorilecees 0s hae 70.2 46.0 58.1 41.4 i eee tee nae e 75.9 48.7 62.3 +1.6 Averages: o-meeae ee 70.7 46. 4 58.6. so aoe aaa SPRING BROOD OF MOTHS. Time of emergence of moths in the spring.—F igure 2 shows graphi- cally the time of emergence and the relative abundance of moths of the spring brood with the corresponding daily mean temperature in degrees Fahrenheit. The records for these observations are given in Table X. CODLING MOTH IN SANTA CLARA VALLEY. Me TaBLeE X.—Emergence of spring moths from wintering material collected on banded trees during 1909. | Number Number | Number Number Date. | of moths. Date. | of moths. Date | of moths. Date of moths. Mar. 30 1 Apr. 17 0 May 5 28 May 23 56 Mar. 31 2 Apr. 18 60 May 6 | 329 May 24 5 Apr: i 0 Apr. 19 23 May 7 | 36 May 25 28 Apr. 2 0 Apr. 20 8 May 8 | 127 May 26 12 Apr. 3 0 Apr. 21 87 May 9 | 136 May 27 21 Apr. 4 0 Apr. 22 99 May 10 185 May 28 0 Apr. 5 0 Apr. 23 307 May 11 97 May 29 0 Apr. 6 0 Apr. 24 333 May 12 84 May 30 27 PTD Tf 1 Apr. 25 152 May 13 127 May 31 0 Apr. 8 0 Apr. 26 61 May 14 74 June 1 0 Apr. 9 0 AND PY 125 May 15 102 June 2 0 Apr. 10 0 Apr. 28 58 May 16 122 June 3 8 Apr. 11 0 Apr. 29 130 May 17 118 June 4 2 Apr. 12 0 Apr. 30 121 May 18 77 June 5 1 Apr. 13 1 May 1 45 May 19 25 June 6 6 Apr. 14 1 May 2 76 May 20 30 June 7 0 Apr. 15 7 May 3 48 May 21 32 June 8 0 Apr. 16 | 18 May 4 | 1i1 | May 22 21 June 9 20 The emergence of the first moths on March 30 and 31 was undoubt- edly caused by the sudden rise in mean temperature about this time, as will be seen from figure 1. Also the period of low mean temperature during the first 12 days of April stopped emergence to a minimum. A rise in temperature from April 12 to 18 brought forth moths again, and the high period of mean temperature about April 22 to 24 caused the first absolute maximum of emergence, then a drop in tempera- ture and a corresponding cessation of emergence, and finally the second absolute maximum emergence on May 6, which was caused by high mean temperature about that period and the rest of the month. After May 18 practically all of the moths: had emerged and no further conclusions could be drawn of the influence of tempera- ture on the emergence of spring-brood moths. Most of the moths emerged during the period from April 15 to May 20 and the maximum period thus embraced about 35 days. The whole period of emer- gence of spring-brood moths extended from March 30 to June 9, a period of 72 days. Time of emergence of moths in the spring versus the time wintering _ larve leave the fruit the preceding year.—In Table XI is given a detailed ~ account of the band collections of 1909, including the dates of collec- tion, relative number of pupe and iene. daily emergence of the first brood moths for that year (1909), and the daily emergence of the spring-brood moths which came from the overwintering larve, the latter being both first and second brood larve of 1909. In Table XI is given also the relative percentage of moths emerging from each separate band collection for the years 1909 and 1910, including totals for each year and a summary of the total moths emerging for both years. As previously recorded by Mr. Hammar,’ the time the 1 Bureau of Entomology, Bul. No. 80, Part VI. 56602°—Bull. 115, pt 3—138 2 AP 124 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. larve leave the fruit in the fall has no bearing upon the time of emer- gence of the moths in the following spring; in fact, some of the larve which left the fruit the latest in the fall of 1909 emerged as moths the earliest in the spring of 1910. The division line between broods probably occurred about August 12 to 16, and by examining the table of the emergence record of 1910 no difference can be seen between the respective dates of emergence of the moths. . Relative percentage of larve wintering from band material and per- centage emerging as first-brood moths the year the larve were collected.— An examination of Table XI shows that 65.3 per cent was the highest number that emerged in 1909 for any single band collection and 6 per cent the lowest. No moths emerged in 1909 from band collections later than August 31. Of the total number of pupz and larve collected from all the bands for the entire season only 28.31 per cent emerged as first-brood moths for the year 1909. One curious fact of the per- centages that emerged in 1909 from each band collection during that year was the sudden rise in percentage to 39.6 for the lot collected August 19, after the percentage column had begun to dwindle to smaller proportions. It will be seen from a glance at the table that the moths emerged from this collection from September 11 to 16 and this may be explained by the very high mean temperature during this period. Just why the high temperature influenced this one collection and none of the earlier or later collections is difficult to explain, except that this particular collection was the first important collection of second-brood larve. A very unfortunate thing happened during the winter of 1909-10, in that the first three jars and also jar C-10 were nearly filled with water and consequently all of the overwintering larve were drowned before being noticed. This caused to a great extent the small total percentage emerging in 1910, or 21.25 per cent, which might have been 30 or 35 per cent. The total percentage emerging for both years 1909-10 from the total amount of larve and pupz collected was 49.56 per cent, the re- mainder haying died naturally or were in the four jars filled with water. It will be noticed that the highest total percentage emerging for both years from any separate band collection was 88.4 per cent and was from the previously mentioned collection on August 19, 1909. CODLING MOTH IN SANTA CLARA VALLEY. 125 TaBLE XI.—Adult emergence of the first and spring broods from band material collected in 1909. wm Number col- Emergence. Dae lected. Jar No. ealieetiqn: Total. Larve.| Pupe. | 1909. 1910. 1909-10. | Num- Per Num- | Per Num- Per 1909. ber. cent. | ber. cent. ber. cent. C-3 | June 21....; 1,602 215 1,817 403 DOTS Seater a ete oe 403 2328 C—4-5 | June 28 2,276 79 ZOO | 678 PASSAT SAIGE AES SECO e 678 28.8 CE7/-l| dibthy Gosek 946 159 | 1,105 722 GOMS i eet tamer Em pra E220\GnGoaS C-8 | July 9...-.- 804 93 897 427 47.6 122 13.6 549 61.2 C-9 | July 12 761 59 820 295 35.9 121 14.7 416 50.6 C-10 | July 15 885 68 953 496 HZAQ | eae st | een 496 52.0 C-11 | July 19 919 48 967 433 44.7 141 14.6 574 59.3 C212 haliy7 22 536 37 573 260 45.3 74 Iaigal 334 56. 4 C-13 ; July 26 505 30 535 148 26.5 143 26.5 291 53.9 C-14 | July 29 350 22 372 79 PAGS? 133 30.7 212 56.9 C-15 | Aug. 2 297 22 319 48 15.0 115 36.0 163 51.0 C-16 | Aug. 5 180 16 196 4 220 42 21.4 46 23.4 C-18 | Aug. 9.... 185 7 192 26 13.5 47 24.4 73 37.9 C-19 | Aug. 12... 115 10 125 9 | lew §2 65.6 91 72.8 C-21 | Aug. 16... 112 4 116 18 | 15.5 55 48.2 73 63. 7 C-22 | Aug. 19 262 2 264 105 | 39.6 129 48.8 234 8. 4 C-23 | Aug. 23 383 0 383 18 4.6 193 50. 4 211 55.0 C-24 | Aug. 26 403 3 406 3] LY 223 54.9 228 56. 1 C-25 | Aug. 31 477 4 481 3 -6 267 55.5 270 56. 1 C-26 | Sept. 2 371 4 aod bewseossl asso sear 210 56.0 210 56.0 C-27 | Sept. 6 580 0 ‘HeVe lbaao case seseaone 257 44.3 2 44.3 C-28 | Sept. 9 381 0 Stoll lll Sperm eee Sem ese 258 66.9 258 66.9 C-29 | Sept. 13 253 0 PERN oot aes clscasesoe 328 72.4 328 72.4 C-30 | Sept. 16 359 1 BUM lace Santa seeenace 157 43.6 157 43.6 C-31 | Sept. 20 290 0 Pe Eee sl Eee eras 116 40.0 116 40.0 | | Total 14, 232 883 | 15,115 4.177 27.63 3, 213 225 7,390 | 48.88 Time during the day when moths emerged.—No tabulated record was kept to show the time during the day when most of the moths emerged, but observations showed that they issued in numbers after 4 p. m. and supposedly during the night. Few emerged during the period from morning after 9 o’clock until in the evening. The emergence record was therefore usually taken each morning before 9 a.m. and included moths of the evening and night before. This seems at variance with the records obtained in 1911. Period of oviposition.—The first moths that appeared the latter part of March failed to oviposit since only a few individuals had appeared until April 18. No difficulty was experienced in obtaining eges in confinement when a number of moths were placed in a cage at a time. No eggs could be obtained from single pairs of spring-brood moths as was possible later with those of the first brood and hence no data was obtained as to the number of eggs a single female can deposit. The first eggs were obtained April 26 or about from 3 to 4 days after moths began to emerge in numbers. The period of low mean temperature from April 26 to May 5 (see fig. 28) caused very few eggs to be deposited, but by May 7 and from then on until the end of the month large numbers were obtained. Oviposition in the field prob- ably extended from April 10 to June 20 (about 10 days after the last moth appeared), or a period of about 80 days, this giving a wide 126 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. range for developing first-brood larve. Maximum oviposition oc- - curred from May 7 to 20, or from 15 to 30 days after full bloom on most varieties of apples. No records were kept as to the length of the oviposition period for individuals. Oviposition was observed throughout the day, but chiefly in the evening and at night. FIRST GENERATION. FIRST BROOD OF EGGS. Incubation period.—Practically all of the spring brood of moths that emerged were utilized for egg records and were placed in Riley cages, where they oviposited on apples suspended from strings. The apples were removed each morning and transferred to jelly classes and kept under serial numbers. It was found necessary to cover the glasses with a fine piece of cloth in order to keep out hymenopterous egg parasites. Table XII shows a complete record for 720 eggs deposited from April 26 to May 17. TaBLE XII.—First-brood eggs. Incubation period of eggs laid in rearing cages. | | Red ring. | Black spot. | Hatched. | Nowot Num- | Date of SSS Leen apple We of Gaposy Date of | Num- | Dateof | Num- Num- of 86 88S. : appear- | ber of | appear- | berof| Date. ber of Be. ance. eggs. ance. eggs. eggs. Days. May 1 5 | May 10 1 1 8 | Apr. 26 tMay ; 3 May \May 13 8 17 ay 9 4) Ma = y 16 6 | May 17 1 10 2 18| May 7 {May 0 { (May 17 4| May 18 Serpent May 10 1 | | ay 18 3 10 3 20| May 8 May 11 2 |\\May 17 9 May 19 Sieh May 12, 9 (May 18 7 M 20 1 12 May 13 7 | ay May 12 6 | ay 20 6 11 May 13 8 ||May 17 3 ||May 21 2 12 4 22 |May 9 }May 14 1 }May 18 15 |;May 22 6 13 May 16 1 ||May 20 3 ||May 23 1 14 May 17 7 | May 24 2 15 5 2| May 10}| May 13 2| May 18 2| May 20 2 10 6 3 | May 11 May 14 2 | May 20 3 | May 22 3 11 ay 13 18 | May 19 3 é May 14 4| May 20 ea eee UO ean - 218 | May 13 May 15 71 | May 21 68 y Ny ~ l>May 24 30 | 11 May 16 53 ; May 22 102 ieee OE 42 12 May 17 25 | May 23 | ts 66 13 Moy 18 6 | May 24 all saad ay 19 5) May 20 1 ||May 26 van bye Be eae 8 186 | May 18 |{May 21 17 |\‘May 27 50 hee 30 30 12 | May 24 34 ||May 28 30 |lTuee 1 14 14 ay 26 7 May 21 3 | 9 16-| May 19 {May 24 6 May 28 9 \yune 1 14 12 May 26 6 May 29 6 | av 24 W May 26 30 | May 28 25 8 10 52 | May 20 May 2 jl \\May 27 16 | May 30 15] 10 as sa 28 4| June 1 10 11 May 22 3 ay 28 2 u 26 | May 21 {May 23 2| May 29 ie | eee wt aaaer May 24 4 | May 30 3 1D tel May: 422 Faroe tees lees cos May 30 1 | May 31 1 9 CODLING MOTH IN SANTA CLARA VALLEY. Mo TABLE XII.—First-brood eggs. Incubation period of eggs laid in rearing cages—Contd. Red ring. Black spot. Hatched. Num- | Date of aoe GOT PCM No. of A 8 apple. nee ees Date of | Num-| Dateof | Num- Num- of we 885. * | appear- | ber of | appear- | ber of | Date. | ber of | 5°48 ance. eggs. ance. | eggs. eggs. May 14 12 pas May 2 May 15 13 ||May 20 1 || Bed Ble Mae May 16 29 |{May 21 23 y ; 13} 132 | May 14 se iiaMlay, 2509 80h) vit May 17 16 |(May 22 61 NA OG 16 12 '|May 18 36 ||May 23 30 |laray 37 ie ; May 19 2 J HE 3 May 20 | 1 ee 16 3 ||[May 21 3 ||May 25 25 | 10 14 69 | May 15 M May 22 15 |}May 26 23 11 ee a : May 24 31 ||May 27 13.|.. 2 ; ay 25 14 ay 17 1 re oe 2 Mey 24 2 8 2 = ye ay 5 | May 26 2 10 15 24 | May 16 {Mav i. I May 24 9 | May 27 Bihan May 26 | 3 | May 29 | 22 13 Mon i “3 ||May 24 | 1| May 27 it 10 16 100 | May 17 May 20 16 May 26 32 | May 28 | 55 1a May 22 8 May 27 | 48 | May 29 | 10 12 | | ! i In all 897 eggs were deposited and 720 hatched, or slightly over 80 per cent. The maximum length of the egg stage was 17 days, the minimum 8, and the average 12.4 days. (See Table XIII.) The red ring appeared after from 1 to 8 days but averaged trom 2 to 5 days. The black spot appeared from 6 to 15 days after the eggs were deposited but usually appeared after 8 to 9 days. An examination of Table XII shows that after the first lot of eggs had been deposited the length of the egg stage was fairly constant throughout the oviposition period of the spring moths. As has been observed by other writers, eggs which were deposited on the same day sometimes varied from one to three days in the length of the egg stage. This was due to differences in embryological development of the eggs within the body of the female. TaBLeE XIII.—Jncubation period of first-brood eggs. Summary of Table XII. Days of Observations. incuba- tion. Average..... 12.4 Maximum....... 17 Minimum........ 8 A summary of the incubation periods for the total number of eggs deposited by the spring-brood moths is shown in Table XIV. 128 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaBLE XIV.—Showing the variation in the length of the egg stage as recorded in Table XII. able : | | Eggs Days. || Eggs Days } | 27 8 96 13 ol 9 15 14 181 10 | 2 15 209 tte 0 | 16 | 131 12 | 8 | 17 | | | FIRST BROOD OF LARVA. As has been already stated, a number of the first-brood larvee do not transform with the rest of the brood, but cocoon for the winter and hibernate with second-brood larve. In rearing the codling-moth larve to obtain the time spent in feeding and the life cycle of the first generation, apples were used upon which several eggs had been deposited, in order to insure some of the larvee living. A number of the larve transformed within the half-dried apples and consequently only partial records can be given concerning them. Time of hatching.—The first larve in the rearing cages appeared May 13 but these did not come from eggs deposited by the earliest moths on account of insufficient numbers of the latter. It is very probable that the earliest larvee appeared in the field from about April 20 to 25 if the time of emergence of the earliest moths, from March 30 to 31, is taken into consideration. As no effort was made to secure data as to when the latest larve hatched in the rearing cages this can not be given, but the latest hatching larvee of the first brood probably appeared from about July 1 to 10, consid- ering the time when the last moths emerged. 7 Number of larvx developing in one apple.—In practically all of the rearing work to obtain a record of the time of feeding of the larvee apples were used upon which a number of eggs had been deposited. In some instances as many as 20 eggs were laid on one apple but in no instance did a large number of larve mature. An examination of Table XV shows that usually one larva left the fruit, two larve left the apple in five instances, and three larve in one instance. In apples Nos. 11, 12, 13, 14, 15, and 16 a number of larve transformed, the number varying from 2 to 5. This seems to have been unusual according to the writings of other authors and was undoubtedly abnormal. Period of feeding of larve in fruit—In Table XV is recorded the feeding period of 46 larvee which entered 16 apples, of which 27 left the apples, the rest remaining in the fruit; 31 larve transformed, 13 wintered, and 2 died. Of this number 25 transformed in the fruit, and 9 spun their cocoons, evidently intending to winter in the dried and shrunken apples. CODLING MOTH IN SANTA CLARA VALLEY. 12 9 TaBLE XV.—Larve of first brood. Feeding period of transforming and wintering larvex; length of life cycle of first generation. = Larveentered| Larve left eB apple. fruit. S ~~ a ~ « 2g gs s8 & | Date. — ES Date Es Z As Zs 1| May 9j| 4] June 11] 1 June 13] 1 2 .--do....| 2 June 19} 1 Slee dOssa = 2p suney One 2 AWE do seet | edo. ws: 1 5 | May 11 {| 1 | June 22; 1 | 6| May 13| 2/ July 1] 2| 7|..-do....| 2|/July 5] 2| 8 | May 18] 5| June 19] 1 9) |Bzdots. $2 4| June 22] 1 10| May 19| 3| June 9} 2| | SAS doss-- 5 | June 22} 1 | sJune 30) 1 12 | May 28] 3 {suly Sulbia ifsialye. Ae ok 13| May 2] 34ny 3] 4 14e une tel eSsebuly, Sloss = June 30] 1 | 15 400: 2. 4 {rary 1 ze AG? |e do2 == PAN AR Tih 19. 2 | 1 Wintered as larvee. fruit. Time spent in Larve spun Larve cocoons. pupated. a) Da Hey se IOI Locality.|& | Locality./& & As AS | Inapple.|....| Inapple.}.... BC Ce eee) ee ee ieee Aleese ROS eel aealees doz Be Besa ae oe booeoe ese I ai9z = do: ..| Inapple.!_-_-. HOS. seis EAE ees lee hs 8 do: 2 ‘Inapple.}.... #200 S252) 2 25 sles. Ones (2224 SR eae eae 23d0:22 sedate eLe do See Pate LEGO. s..|552 doses lees eados Aug. 11 1 Se sel eee Inapple.|..-.| Suilyaele ee eaalyee eles ot Silygs Siig leer eA Suly. Seat sulye 285) 0 July 22 1 |eomoe Sesce July 2] 2| July 22] 2 Iaalys eS |p Sal yaec on | iel al |iememe ee Hide. 4s 1| July 14] 1 July 12) 1] July 22] 1 2 One wintered as larva. Adults emerged. Length of pupal stage. Total time spent in cocoons. Number of larvee. iS} © os © ‘Days. Days. | 3 Two wintered as larve. | Theoretical length of life cycle. Hee He He He He (HUalVESZOF |. LL eee ee (2 | See ie | act {ruly Dhl vyds | eye daee ee ak (Be ee eee Sc 8 July ig) Pes Soemeg |e 2 A = AUR ANE Nh Sal eee ee oe FulivsS LOR eee | ee eee VN CG oe el bel (eee as es PNY ell’ Sh el (ae em en Rae eB uly, WG ne i eee eee Sulypisy | iy ete ee eee Siuly, 1a Ds eee ee dual seelO) | Een || Sess eres ANTON TST iene erent ee ID TIX6 Page sae eso on) |scsoss bo slen iethiyens S| ee |e eee eee Saky iON le eee See ee Silly; UO be oe: | es eee TOUR ort sat eed bul ors Se eee duly, AON 9 9 Aug. 19 1 22 42 (Cae tel (geet I Se dee eo Ate = 52 14 34 @z® |2O | 4284) Bes) pee July 28} 1 14 20 Aug.15! 1 24 34 In Table XVI a summary is given of the time spent in feeding by the larve as shown in Table XY. TaBLE XVI.—Feeding period of larve of first brood. [ Time Observations. spent in | fruit. Days. AtveTage 254-5 = 5 38. 1 Maximum =--.---— 53 Minimum oss 29 Larval life in the cocoon.—Individual records were kept upon the time of cocooning, time of pupation, and emergence of the moths on Under this heading would be placed the post-larval stage or the period between the first 141 larve. spinning of the cocoon and the time of pupation. (See Tables XVIII and XIX.) in the length of larval life in the cocoon are given in Table XVII. The variaticns 130 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaBLeE XVII.—Larve of the first brood— Variations in the length of the larval life in the cocoon. Post- Post ost- Post- Number Number Number Number of larve. aoe of larve. ets | of larvee. ee of larve ae \| | Days. ' | Days. || Days. Days. 3 2 1 10 2 21 1 31 2 3 3 11 3 22 i 36 12 4 3 13 3 23 1 39 ibe | 5 3 Gia 2 25 1 39 38 6 4 17 | 1 26 1 40 7 7 2 18 2 27 1 41 4 8 1 19 4 29 1 50 12 9 1 20 3 30 From Table XVII it will be seen that the average larval life in the cocoon was 11.7 days, the maximum 50 and the minimum 2 days. The average post-larval stage is considerably longer than given by either Mr. Jenne? in Arkansas in 1908 or by Mr. Hammar? in Penn- sylvania in 1909, in their studies of the codling moth. The former obtained an average of 7.2 days, a maximum of 19 days, and a mini- mum of 3 days, while the latter obtained an average of 7.09 days, a maximum of 19 days, and a minimum of 3 days. FIRST BROOD OF PUPA. Time of pupation.—The first pupe observed in the field were col- lected from under the bands on June 6 and from then on weekly to August 15. The first pupa observed in the cages was on June 25 and the last on August 20. Pup appeared in maximum numbers in the cages throughout the month of July. Considering the date of the emergence of the last moth on September 22 and subtracting the average length of the pupal stage, the date of the last larva pupat- ing must have been about September 3. Length of the first-brood pupal stage-—The larve upon which the pupal records are based were collected from banded trees in 1910. One collection was made June 10 of 46 larvee and one June 20 of 95 larve, making a total of 141. In the first collections 11 larve were males and 35 females and in the second 27 individuals were males and 68 females. The sex of the larvee was determined in the same man- ner as was that of the overwintering larve. (See p. 122.) Table XVIII shows a detailed record of the 38 male larvee which had an average pupal stage of 19.5 days; Table XIX shows a detailed record of the 102 female larvz which had an average pupal stage of 18.8 days. From records of the overwintering larve and similar records for 1911 it was apparent that female larvee required a longer pupal period. The above record seems to contradict the other records as 68 female larve, or 66 per cent of the total number of 1U.S. Dept. Agr., Bur. Ent., Bul. 80, Part I. 2U.S. Dept. Agr., Bur. Ent., Bul. 80, Part VI. CODLING MOTH IN SANTA CLARA VALLEY. Kall females, were collected on June 30, the second collection, while 27 male larve, or 71 per cent of the total number of males, were taken on the second collection. It is evident therefore that a larger per- centage of the total number of males was influenced by a higher mean temperature (on account of later collection in June) than females, which would naturally lead one to expect a shorter average pupal stage for the males in comparison with that of the females. Possibly a few individuals with a long pupal stage in the male series of 38 individuals caused a greater influence on the average length of the stage than the same number of individuals in the female series of 103 larvee would do. The average length of the pupal stage of all the larve was 19.04 days, the maximum 55 and the minimum 11 days. (See Table XX.) Asummary of Tables XVIII and XIX is given in Table XX, showing the variations observed in the length of the stages during the entire period when pupe were found. TaBLE XVIII.—Pupe of the first brood—Length of the pupal and cocoon periods of 38 male larve collected in 1910 on banded trees. Date— 5. S28 Date— 5 BAS 3 SP ss Se | ss Ss ~ ~P e aise (NO ga | 3% ee opr tel 0) cepun Pupated. Emerged. aia 28 codoon, | Pupated. |Emerged. fS,| 28 4 =) 4 4 Days. Days. Days. |Days. 1] June 21 | June 25 | July 11 16 | 20 20 | July 1] July 7| July 22 15] 21 2 Osea: June 27 | July 14 17 | 23 PAY Woe eGWOB esa: Ones July 20 13 9 3 do..... June 25 | July 17 22 | 26 DPN ea Gea as Aug. 9 | Aug. 28 QE ast ee 4 do..... June 27 do..... 20 | 26 23 | July 1) July 7/1] July 23 16 | 22 5 do..... RCO see! do..... 20 | 26 QA ee dolane Aug. 11] Sept. 2 32 | 63 6 | June 22} July 1 | July 19 18 | 27 2 Dad Oseeee July 5] July 20 Typ ag) au do..... July 9| July 27 18 | 25 26 mesdoseaee July 23 | Aug. 16 24 | 46 8 do..... July 19 | Aug. 9 21 | 48 Di NE eC hae Aug. 10 | Sept. 4 25) 65 9 | June 24 | June 30 | July 17 17 | 23 28 edosss: July 27 | Aug. 15 19 | 55 10 OVE June 20 | Aug. 10 21 47 ZO MeeOneaee July 7] July 21 14} 20 LS Senorita July 12 | Aug. 1 20} 38 OME IsCoOyes se. July 28 | Aug. 25 28 | 55 12} July 1] July 30/| Aug. 24 25 | 54 SU eS OK sees July 7 | July 20 13} 19 13 (ees July 24 | Aug. 13 20 | 43 32 | July 2] July 9 July 27 TSse 125 need ones): done: Aug. 16/ 23] 46 331 dow sae! Sally) vSe |) July, 24eye alonlnn oo 15 do..... July 19 | Aug. 10 22 40 34 |...d0....: July 7 Goss 17 | 22 16 do..... July 51} July 20 15 | 19 BON aed ouee Aug. 1] Sept. 1 31} 61 17 do..... July 7 | July 23 16 | 22 36 | July 4) July 14 hes. a3 20} 30 18 do..... One? July 27 20 | 26 37 | July 11) July 15 dow 19 | 23 TONER uty ae Gog UDA PE (Te 3 i 38 | July 12| July 16| Aug. 7| 22] 26 #32 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaBLe XIX.—Pupz of the jirst brood. Length of the pupal and cocoon periods of 103 female larvz collected on banded trees, 1910. — . Ss 5 i} _-. — | | Date— of | cm] | Date— of8lo = sf | <= | 8 | ‘No. | S21 SE || No. || S= =e | Spun | ea | @o | Spun | eg | &S | cocoon. | Pupaied. oral == gg | cocoon, |/ Upated.|Emerged A) gg ee] | fea eal | | uy Ae | | | | | i | Days. | Days. | | Days. Days. | 1) June 21-| June 25| July 13| 18 | 22 || 53 || July 1] July 7] July 21 14] 20 (ab MOS ee June 27| July 15/ 18] 2 ]) 54 |j_--do..... | July 9] July 23] 14] 22 ee 4 des ot do. | July 17 20) 26 || 55 ||-.-do____. July 7 | July 24 / fl ees > 4 dos June 26 | July 15 19{| 24]) 56 |]_.-do_...- | Aug. 20 | Sept. 18 29. «79 Cech eee June 25| July 17| 22 |_....- 57 ||_.-do.....| July 7|July 2] 16] 22 be POueeeeraees June 30 | Aug. 24 TF) eee W° 38° Ye. dole edo. July 21] 14) 2 7 | Jume 21 | June 25 | July 14 19} 23] 59 Si Pee es do. July 20 13} 19 8) |-=-do:--= June 30) July 18 18 27 || 60 |j..-do.-_-- July 10 | July 27 | 7| 26 9} sdores 2 June 27 | July 17) 20} 26) Gi jj-.-do-_-2-- July 8| July 24; 16) 2 | Ou ido! Ral iedas. *<: July 15/ 18] 24]/ G2 |!_._do._._.| July 7] TJaly 20] 13] 19 | ALAS tote fe dat. 3 July 17| 20] 2614] 63 |j__-do.....} July 14] Aug. 1/ 18) 31 [542 |...do--..- | July 11| July 27} 16| 36]| G64 |j_--do____- | July 18} Aug. 7| 20| 37 Diets de June 27| July 17} 20| 26/]| 65 ||...do._...|July 7| July 21| 14; 20 age (odo * June 25| July 13] 18; 22|) 66 |}...do_....| July 17} Aug. 7| 21; 37 | 15 |-2:do.---_| June 27 | July 17| 20) 26] 67 ||1do-_..| July 7z| July 23] 16| 2 ter cdes. = Aug. 1/| Aug. 31/ 30 71 || GS jj_..do__-_. ic vdoes se July 21 14, 20 17,1 adores June 30} July 18| 18| 27 |] 69 ||_.-do.... July 10] July 28] 18| 27 rf), ba eed ae he In does * 18| 27 || 70 ||__-do.....| July 17| Aug. 6] 20] 36 19s) 2 do. July 21 | Aug. 15 25) 35 a Ne doteez | July 12} July 31 19 30 OE dps June 30| July 17] 17| 26/| 72 |{..-do___.. | July 23} Aug.19| 27| 49 | 2 dos June 27 | July 15 180) 24 ll edo: dor Aug. 16) 24/ 46 oe das es do es (July 17) 20] 26]] 74 |i_-.do.____| July 7| July 24) 17| 23 pars dase July 2| July 2| 18] 29]) 75 |j---do___.- July 22] Aug.15| 24) 45 245 dos June 30) July 17 (a lore 1 16 | 2do == July 3; July 22 19} 21 25 | June 22 |.._do-..-. July 18 18 26 lie) -de=_ July 14| Aug. 3/ 20! 33 Jae el RI epee June 297}5 dor) 19) [a He 78" te dou 2 = July 3 | July 20 17 | 19 27 | June 22 | June 25/| July 13| 18] 21 || 79 ||_.-do..... July 10| July 21} i1| 2 aie Gos = July 1) July 20 19} 28) 80 July 2)|. july. 6 {> do-== 15 | 19 | 29 |" -do.___.| July. 3 |__-do.____| 17| 28|] si ||_-do._.| Fily 9| July 25) 16) 23 30))- i doe. - | June 30 |-..do__-.- 200) 281) S23) Slo 2s | July 25] Aug. 18] 24| 47 | 31 j...do._.| June 27 | July 17; 20) 25;) 83 j-.-do...| July 7| July 21) 14] 19 | a2 |. do__..-|.2do_22-|-do.2|-20- | 25 |] ge Wi sdosl. edo: =e July 20] 13] 18 | S35) epee s || 2) don dos 20) 1-24 Sb dane 31= do eLO lee 4. GOsaaa Le 6 |.--do..... ESBS Le c Nie: 23 2 | Aug. 35 i] 2 113 27 | Aug. 14 |...do..... OFM dose 27 { es 4 ee Aug. 24| 22] 10 114 BOI ts dows alle edo. ea 201 |aedoses 30 { Ages 25 | ; 1 Aug. 24 22 115 Sido 2 alte do: D8n| Redo. ee 28 { Aue 25 eileen 116 49 | Aug. 15 doses. 49 | Aug. 24 495): dOse= 48 10 117 51 dole dome 51 dosas-€ 5 |Sedos= at 0 118 37i|be dos. Ole 39 |Si-do. 37 eee 3 rT Aug. 18 WH lege Me ecas [Or Sedo 56 10 119 81 | Aug. 16 Vie. 19 55 | Aug. 25 62 | Aug. 27 Detlef io PA les fang. 18 30 | Aug. 24 29 | Aug. 26 a0) Sab ee bacon Aug. 19 30 | Aug. 25 31 | Aug. 27 30Hey At 121 Ale ea Aug. 18 20 | Aug. 24 40 | Aug. 26 44 | 10 eA besa Aug. 19 26 | Aug. 25 : Aug 27 2 2 | = Ose AY see One Sedowese 7 122 11 | Aug. 17 Nave: 21 6 | Aug. 26 5 | Aug. 28 | AN ed 11 123 23 d Aug. 19 10} Aug. 25 11 | Aug. 27 15 10 eg Aug. 21 12| Aug. 26 12| Aug. 28 8 11 124 19 BG Aug. 19 8 | Aug. 25 8 | Aug. 27 12 10 -- -GO.---- Aug. 21 11) Aug. 26 11 | Aug. 28 7 11 Aug. 20 1 eee Ko eee 125 3 | Aug. 18 { eee 2 | Aug. 3 \aug. 30 3) 12 | Aug. 20 2 ug. 2 wes 4 |---do..... Aug. 21 2 | Aug. 27 3 ee : sa Aug. 20 Sevag eet 3 | Aug. ad 4) Bderese ate cy 2| Aug. 28 1| Aug. 30 Thea to 128 11 | Aug. 19 |...do..... 1 Ane on ol da.cae Tp TaBLE XXIV.—Second-brood eggs. Incubation period of eggs laid in rearing cages— Num- ber of apple. 129 130 134 56602°—Bull. 115, pt 3—13——3 CODLING MOTH IN SANTA CLARA VALLEY. 139 Num- ber of eggs. e bo — CO STOO a, “I wor — © 00 as w w no re | hb He OTR rhc Ww Continued. Red ring. Black spot. Hatched. Date of |=] |__| Tenth! copes: Date of | Num- | Date of | Num- | | Num- a ©88 i appear- | ber of | appear- | ber of Date. | ber of Stee: ance. eggs. ance. eggs. | eggs. | | Aug. 21 3 | Aug. 27 3 pee ‘Aug. 21 | ug. 27 | -s Renton || Aug. 22 3 | Aug. 28 1 {aee 20 d 8 Aug. 23 2} Aug. 29 Su lijmeee 2 Aug. 24 il do Aug. 23 5 | Aug. 28 2| Aug. 30 10 10 eer Aug. 24 3 | Aug. 29 14 | Aug. 31 6 1l a me Oss 5- 1 | | Aug. 21 { ee jAug. 30 8 | Sept. 1 Sh ae dos. Aug. 24 Orie do? le | AO a es 11 Aug. 22|...do..... 5 mug a ia |\ = doses 9 10 2d0== Ease 3 | Aug: 30 Snleedorses - 510 SOO S555 [eee Ole a. 1 | Aug. 31 1} Sept. 2 1 11 og = ..do weer 4 } | Aug. 23 ae 25 4 {ont i 3 | ae beets ne | - Aug. 24 4) i{-2dou=: 5 .do eee (ue: 26 8 i _do -ceee 19 {Set 3 4 | 11 = (Sept. 3 10 Aug. 25 3 \ | edors-- S02. 524 8 Sept. 3 3 | il Aug. 26 3 '|Sept. 4 2| 12 done: 7 11 Sept. 2 2 Aug. 24 |...do....- 3 { USept. 5 le | : ae 3 2 [Sere 6 elle AB | ept. 2 9| Sept. 4 9 11 -do.....)...do..... 10 |\Sept. 3 2| Sept. 5 | Dale 19 Ed Oee 524 |= GOsstee 1 Bet: 2 3 | Sept. 4 | 3 11 x s ept. 3 4 | Sept. 5 2 | 11 2 | ee ie {Seot, 4 2| Sept. 6 Ps Sept. 5 1 11 -do.. (6 Colao 2 cee 3 2 Heeet 6 1 12 | sdons |i donc! 3 Haepte a Tih domesel) erate ae? Sept. 5 Ds dows. Shite he SESS 2b | ae 2h 1 sept. 6 2| Sept. 7 Be ee dow ale doxc.2 10 | Sent 2 alee a| 12 dost -|= do. 8| Sept. 5 iQue Oee= 17 | 12 Aug. 27 | Aug. 30 2)| Sept. 6 11 | Sept. 8 11 | 12 Ose | eos eee 33|e22do0s.-55 Geiss=doss--+} 6 | 12 Aug. 28 d022-:- 2) Sept. 7 5 | Sept. 9 5 | 12 200°== 2/52 doses: 2A\B=dores- 4 Paes xt 12 Sept. 8 10 | Sept 12 Aug. 29 | Aug. 31 3 \Sept. 9 2| Sept. 11 3 [12 Edoee el dors. 7 | aoe . 3 i\sept 10 Bile oa) e Sat sace 2 | Sept. 11 IPA eal hag BD) aod 19 \Sept. 10 21 | Sept. 12 9| 1B | Sept. 9 1 | Sept. 11 2 | 12 | J Dagode aCe 4 Sept. 10 3 | Sept. 12 2) 3 | are Sept. 9 6 Bane 11 1g i 12 PdOs=222|---005.2: 11 ept. 12 1 13 | sen 10 8 {Sent 13 21) ta Aug. 31 {eebe 3 “fests 2| Sept. 12 zie 1 paedOse=ss|-.-GO2. 5 12 | Sept. 11 2) |S 2dOs 2 1 12 Sept. 2| Sept. 6 2 | Sept. 13 2 | Sept. 16 2 14 d d pa dag as 4 | Sept. 15 2 | 13 eee | ‘ \\Sept. 14 2 | Sept. 16 4} 14 a sdaaes: |) -Go-cste 7 | Sept. 13 11 Seep S25a4 “ E ~ Sept. 14 6) |22-d0= | Sept. 3| Sept. 7 8 Sept 15 2 | Sept. 17 2" i = ~ |fSept. 16 2 | : See a ee | 5 | Sept. 14 5 Sept. 17 3 14 o ~ |fSept. 16 | 2 | do wees .do weces | i |7 .do cesses ‘ Bept il7; | 2 | a = 2 moe | ECs (RERISE Bd Osea |e dOlsaa- | 5 | Sept. 15 5 |\Sept. 18 1 | 14 | 7 | Sept..4| Sept. 8| 3 |_..do...... 5 | eeer 18 Ae Sept. 5| Sept. 9. 1 | Sept. 17 2| Sept. 19 oH eae! dorsass| 52 dos2 5 4d ee Ceri 2) a= =dOsne=- 2 | 14 Sept. 7 | Sept. 10 | 1 | Sept. 19 1 | Sept. 22 1 | 15 Sept. 9 | Sept. 11 7 | Sept. 21 11 | Sept. 24 te| oo =15 do Seo (oa 11 Pears been PD. 250 (ase 2 | 15 G0s=-5 Sept. 13 2a dOsae=s 2eltee des ea= 20 15 140 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaBLE XXIV.—Second-brood eggs. Incubation period of eggs laid in rearing cages— Continued. Red ring. Black spot. Hatched. | Num- | Num- wate of ; a | ber of | ber of | deposi- | pate of | Num-| Date of | Num- Num- | 2 ©88 apple. | eggs. | tion. | anpear- | ber of | appear- | berof| Date. | ber of | Stee ance. eggs. ance. eggs. eggs. | | Sept. 22 3 | Sept. 2 a | So { | ept. ept. 25 2 5 174 | 8 | Sept. 10 | Sept. 13 8 {Sent. 23 2 | Sept. 27 3 17 | rs Sept. 22 2 | Sept. 25 2 15 175 Boles oo aoc econ 3 Sept. 23 1 | Sept. 26 1th 6 = c | Sept. 22 11 | Sept. 25 10 1S 176 | 13 |-.-do.....)-.-do..... 13 {Sent 23 2| Sept. 26 31» ste. 4 Soil alice \fSept. 15 Glee cOOscoot 3) | septs 25 1 14 178} 12'| Sept. 11 {Sept, 17 3 | Sept. 24 9 | Sept. 26 isl 15 179 | 1 | Sept. 12 | Sept. 15 1 | Sept. 26 1 | Sept. 27 1 15 180 | 5 | Sept. 14 | Sept. 18 Divers dona 5 | Sept. 29 5 15 | 181 | Gleedowe-2|2 edos-o 6 Nee jee eck 6 15 182 | NWS dieeeO boson fendOsoee 7 | Sept. 26 13 OOsece= 13 15 183 | 1| Sept. 15 | Sept. 19 1 | Sept. 27 1 | Sept. 30 1 15 184 6 | Sept. 17 | Sept. 20 6 | Sept. 30 GrinOGtaes 2 6 15 185 Sy le eO soe Hee GLOSanee 5: | Reed ole ee (eee doneee uf 15 186 3 | Sept. 18 | Sept. 22 2) |,Oct, 3) O@in & 3 15 187 35 2sedore.2 aa CO ee SRE OS eRe 74 laa Onan 2 15 188 3 | Sept. 21 | Sept. 24 SnOCts a4 | Om 2 15 189 3, | Sept..22-| Sept. 25° 3 | Oct. 6 | 3}.|| OGiis. & 3 16 The length of the egg stage ranged from 7 to 17 days, with an average of 10.92 days. Very little difference in the length of the stage is shown by Table XXIV for the. 78 days or period of oviposit- ing by the first-brood moths. The red ring appeared from 2 to 3 days after deposition usually, the black spot from 6 to 10 days. ; Taste XXV.—Incubation period of second-brood eggs. Summary of Table X XIV. | For ce For appeat-) pop 3 aed Observation. | ance of anceof | : | red ring. | black spot. | bation. Days. Days Days IAVCLAS Ce ae ce eae 2. 64 9, 24 10. 92 Maximum....... 9 15 17 Minimum........ 1 5 7 SECOND BROOD OF LARV. Feeding period.—As mentioned under the egg stage, eggs were obtained from July 9 to September 25, a period of 78 days, and were hatching from about July 19 to October 8. The feeding periods were observed on a number of these at various intervals and devel- oped normally and spun cocoons in the rearing cages in which they passed the winter. The details of these records are given in Table XXVI. . ee CODLING MOTH IN SANTA CLARA VALLEY, 141 TaBLE XXVI.—Larve of second brood. Period of feeding of larve in rearing cages. Date of— D: = : Days | | Bigot Days No. of | of No. of | ) oi LENE | Hatch- Leaving feed LN | Hatch- | Leaving eae | ing. fruit. ins: | ing. | fruit. pass | | | 1 | July 20 | Aug. 29 40 43 | Aug. 20 | Sept. 20 31 2 | July: 20 do 39 AAG See Osea Sept. 25 36 3 | sO eoes dozee 39 Ale eed OfnEE Sept. 24 35 An etd oun = Sept. 11 52 AGE donee Sept. 29 40 Si eidowes. Septsiaa| se) nae ccavaledot ume Sept.28| 39 Gales dozeee- Aug. 30 40 ASH sdOsen. 2 Sept. 23 34 Mee Goses ss Aug. 31 41 49 | Aug. 21 | Oct. 7 48 Oe baO@sccne ard O22 sae 41 | 50 ; Aug. 22 Oct. 18 57 O tee 6@eeces|| es 43 || I le a0 Mecceal| selon 2 34 OE ed Ofsee= Aug. 31 41} 52 doze: Sept. 29 38 11 | July 26 | Sept. 17 53 || 53 | Aug. 23 | Sept. 28 36 12 | July 29 | Sept. 5 38 54). oe dose Sept. 30 38 13 | July 31 | Sept. 28 59 | 5b ee adonewey Sept. 26 34 14 {| Aug. 10 | Sept. 15 36 || 56 RG Ose OG 6 44 15 dos Sept. 21 42 || 57 | Aug. 24 | Sept. 26 35 16 | Aug. 11 | Sept. 15 35 HoH Eee Oa Se Sept. 25 | 34 17 | Aug. 12 | Sept. 20 39 598 | =e dose see Oct. 12) 49 18 | Aug. 11 | Sept. 10 30 G0)/E- doe =: Oct. 151 ° 52 19 | Aug. 12 | Sept. 13 32 61 | Aug. 25 | Oct. 10 | 46 20 | Aug. 13 | Sept. 26 44 (PF Nec oacoe Octa as) 43 21 | Aug. 14 | Sept. 13 | 30 G35 (2 =-do2 Octs 776; | 42 D9e| Mugelohlusept. 1m) 6133 | | 64 | Aug. 27 | Sept. 27] 31 23 | Aug. 14 | Sept | ee Gone mdos et: Oct 6 40 24} Aug. 15 } Sept. 25 4) | 66 | Aug. 30 | Oct. 7 38 Poe OO rn caae Sept. 28 44 O72 GOle-e- Sept. 29 30 26 | Aug. 14 | Sept. 21 | 38 at} oe toe Oct. 16 47 27 | Aug. 15 | Sept. 19 35 | 69 |...do..... Oct 7) 4138 28 O=eeae Sept. 18 34 |] Os | ead Omer Oct 21 52 29 | Aug. 16 | Sept. 30 45 71 | Sept. 1| Oct. 9 38 30 One Sept. 19 34 (4 Nec OWSacse Oct-13) 42 31 dos 22 |=2- 0022.2. 34 73 | Sept. 2 | Oct. 16 | 44_. a2 (Auge 17 | Oct 1 45 TATE RCO we Oct. 18 | 46 $3 don-e Sept. 25 39 || 75 | Sept. 3 | Oct. 19 46 34 | Aug. 18} Sept. 30 43 76 | Sept. 4 Gorse 45 30 | Aug. 17 | Sept. 24 38 |} 77 dower Octs 75 31 36 | Aug. 18 | Sept. 27 40 784|:Sept. Z| Oct. 19) |" | 42 37 OW sanee Sept. 22 35 79 | Sept. 10 | Oct. 18 | 38 38ele dors Se iSepts 24 37 || 80 | Sept. 12 | Oct. 22 40 39 | Aug. 20 |-Oct. 5 48 81 | Sept. 16 | Oct. 21 | 35 AN LEG hee Sept. 26 37 82 | Sept. 17 | Oct. 24 37 Ais \eeedowee Sept. 30 41 83 | Sept. 25 | Nov. 4 40 APA Weta COeer =e OXGiE 3} 44 TABLE XXVII.—Feeding period of larve of the second brood. Summary of Table DERVIS L see Feeding Observations. periods. by | AV OCUASE. coceeeee 40 \ Maximtm)s so 226- 59 Minimum. ...-.-.-- 30 The feeding periods of the larve under observation ranged from 30 to 59 days, with an average of 40 days. It will be seen by com- paring the records of the first-brood larve with these that practically no difference existed between the length of the feeding periods of the first and the second-brood larve. Time of leaving the fruit for winter.—The earliest second-brood lar- vee to leave the fruit in the cages to hibernate did so on August 29, | but were probably one or two weeks earlier in the field. The last larvee in the cages to leave the fruit did so on November 4, which is a bale 142 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. quite close to the time the last larve had matured in the field accord- ing to the band record. The senior author observed a half-crown larva feeding in an apple in a tree November 30, 1911, and it is possible larve could live much longer in the field if the fruit was not picked or would fall from the trees. REVIEW OF LIFE-HISTORY WORK OF 1910. During 1910 the life-history work of both broods of the codling moth was carefully worked out and results of these observations are shown in the diagram, figure 31. This diagram is an effort to depict the condition of the insect in orchards during the season as based on data obtained in the laboratory. Spring pup pee shortly after [eee ee eee Bees | a | AUGUST serene | coum [ey eee ee Sea Pee | at 5 10 15 aa PIE 2025 ae AUT RTT LUTTE LL rhe Be LUA ve A Ae LTT TT bo Mi et anal varneyfaautitaall| TUT ELLLECTHPee rr NH Fig. 31.—Diagram showing seasonal history of the codling moth during the season of 1910. (Original.) the middle of February and continued to appear until June, reaching a maximum about April 4. Moths began to emerge March 28 and continued emerging until June 9, with an average maximum May 4 Oviposition of ‘tthe first-brood eggs extended from April 10 to June 20 with a maximum about May 16, while the larve of the first brood began to hatch April 26 and continued hatching until July 22, reach- ing a maximum about May 29. The larve of the first brood cocooned from May 28 up to August 14 with a maximum about July 3. About June 4 the first-brood pupx were present and continued until Sep- tember 3, reaching a maximum about July 14. Emergence of the first-brood moths commenced June 22 and lasted three months or until September 22, with a maximum about August 4. Second-brood eggs were deposited from July 1 until September 28, reaching a CODLING MOTH IN SANTA CLARA VALLEY. maximum about August 11, while the second-brood larve hatched from July 13 until October 12 with a maximum about August 20. The second-brood larvee cocooned August 16 and on throughout the winter, with a maximum about September 16. The wintering larve of the first brood ‘‘to spin cocoons” began to do so about June 15, but by far the largest number of these came from the second or true overwinter- ing brood. The life cycle of the codling moth from the first appear- ance of the spring pupe until the last larva of the first brood cocooned occupied about six months. The second-brood life cycle from the first appearance of the first-brood pupe up to the cocooning of tlre winter- ing larve in 1911 occupied a period of over eleven months. SEASONAL-HISTORY STUDIES FOR 1911. SPRING BROOD OF PUP. Time of pupation.—Records for the spring brood were kept in two series, one lot in small gelatin capsules, size No. 0, punctured with a pin, and the other in vials. Those in the capsules were taken from under bands in February and out of the larvee thus secured only 41 per cent pupated. Of those that pupated 21.7 per cent died, the majority of these being early pupating individuals. The first larva pupated on March 2, the second March 14, and none after that until the last week of the month. Pupation continued until May 11, on which date the last larva became a pupa. The first adult appeared April 18 and the last June 8. Thus the actual period of time when pupe were present extended from March 2 to June 8, or 98 days. In the field, however, adults were emerging from March 24 to June 20; thus pupe were present from about February 12 until June 20, or 128 days. The longest pupal stage was 49 days, the shortest 30, and the average 41.9 days. Figure 32 shows the time of pupation for both capsule and vial material and also daily mean temperature. These data were com- piled from records of 156 individuals. Second series of larve.—Larve were taken from bands in the fall of 1910 and placed in vials, where they remained through the winter. Of these 25.2 per cent died before pupating and of the ones that developed into pupz 23.2 per cent perished. The earliest pupa occurred March 16 and the latest May 11. The earliest adult issued April 26 and the latest June 11. Therefore the period when pupz were present; March 16 to June 11, amounted to 87 days. The shortest pupal stage was 31 days, the longest 56, and the average 43.2 days. This exceeds the average for the capsule series by 1.3 days. There were 66 individuals in the vial series, of which 32 were males and one escaped before its sex could be determined. No attempt was made to credit any certain sex to the larve while in that stage as was done in 1910. The average male pupal stage was 41.8 days, while that 144 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. of the female was 44.3 days, or 2.5 days longer. In summarizing the two series we find that the earliest pupa occurred March 2, the latest pupa May 11, the earliest adult April 18, and the last adult June 11. The shortest pupal stage was 30 days, the longest 56, and the average ~p & — aunpeyaduiay Ayep abeueny as So 1 8 a. 3 a 6 iS | 3 = = E BE, playuauye 4 i rw March April May Fic. 32.—Diagram showing pupation of spring brood of larvee, 1911. (Original.) 42.4 days. From the total adult emergence record (fig. 33) it will be seen that the earliest adult emerged on March 24 and the last on June 20, so that by using the average pupal period the earliest pos- x oc o a, WL RL & & 9, ss x S&S a ty 2, %) <= few ie) os we °o = Vv Be) € =) LZ cs playuvauye4—aunpeuadwiay Ajrep eBeuany | - AZ OMS mio April May Fic. 33.—Diagram showing emergence of moths; overwintering brood of 1911. (Original.) sible pupa must have occurred about February 9, and thus the theo- retical span of the pupal period included the time between February 9 and June 20, or 131 days. Tables XXVIII and XXIX show, respectively, the pupal stages in the capsules and vials. CODLING MOTH IN SANTA CLARA VALLEY. TaBLE XX VIII.—Spring brood of pup. collected under bands in February, 1911, and reared in capsules. 145 Length of pupal stage of overwintering larve No. of indi- OWONMARWNH bo bo vidual. Date of— Pupa- Emer- tion. gence. dows: May 9 dom May 10 do Ones Mar. 30 | May 13 LOW 5 Nc BA CLONMe ee doree: May 10 doe May 12 Mar: 213). 2do:2..- Mar. 31 | May 13 Clon ess aloes done: RG OW ies nO means doeSee May 15 doe May 12 Gon as May 14 doe May 12 CO Ee lls dome: doses May 14 dow: May 15 doen: May 14 Maree? >see adoreee = Mar. 31 | May 12 doses: May 14 Apr. 1{| May 11 Op sane May 16 do .| May 14 doseen May 15 dos May 16 OO saarc May 13 dos May 16 domes May 13 Apr. 2| May 14 Opa May 15 doses 5 ACO See does May 14 dome Onan do.....| May 15 Apr. 3] May 16 ChOsshee May 19 doses May 16 do May 18 No. of indi- vidual. Date of— Pupa- Emer- tion. gence. EOOsosce May 19 Gomes May 16 Rd OMNES. Bend Oneen Govanes May 20 Apr. 4] May 19 Closter May 17 domes May 18 Apr. 5| May 15 dow May 18 do.....| May 19 doesn: May 20 ACLOwae ae a sCOlOR Bees dome: May 18 Apr. 6 May 20 dows May 18 dona: May 20 Goes Peed ose. dome May 19 Goteee May 20 doses wae OeE = Apr. 9 | May 21 Goneen os OOne sa ANDES, lO) ee ad Of ase Power Peed Ov eae ROR s eA Olney: Apr. 14] May 22 Apr. 15 | May 23 Apr. iG) |eedOcsen. Gove: May 22 pupal 146 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaBLE XXIX.—Spring brood of pupx. Length of the pupal stage of overwintering larvx colbected from banded trees in 1910 and reared in vials. | | | | Date oi— Date of— No. of Len No. of pe indi- | | Sex. || indi- Sex. vidual.| Pupa- Emer- | pope | vidual.| Pupa- |. Emer- pupal | tion gence. | Be. tion. | gence. SESE. | | | | | | | Days. || | Days 1 | Mar. 14| May 6] ¢ 43 1) = 34 |sMar. 31 |sMay 46 |-2--..| 46 2 | Mar. 16} Apr. 26| ¢ 41 || $5 4lss-does May a2 | ie b 42 3 | Mar. 17 | Apr. 29 rot 43 || ie | SEG May 16 Q | 47 ASS ae dor-2 = |sApr: 2S 42 |i 3¢ 71 52-d0=== May 18/ ¢ | 48 5 | Mar. 18| Apr. 30/ Q 43 | 38° 11 dare. May 16 | 3 46 6 | Mar. 20} May 1] © 42° |) -39.5/-Apr. i |.. do. = 2 45 7 hel miso Ce Bia pe May 3] ¢ 44 || 40>) |522d6222" May 18! ¢ 47 8) jae2dems- May 2| ¢ 43 || 41 | .do--2.5 May 20} 9 | 49 Ds (ac dohe.. |eMisty 1 Lees 43 || ~42 |__.do.....|May 27| 9 | 56 10 >) 222d02> 2. rApr. 30 2 41 || 43 | Apr. 3| May 19} ¢ : 46 11 |:Mar. 23 |;"May 4)| 9 44 |} 44% dos |e May, 20 | Q 47 12 |-Mar. 24| May 5] ¢ 44 || 45) | Apr..25 | May 21 | Q 47 13 cdo. -2-* May 8} Q 45 || 46 | Apr. 4 |...do..___| 2 47 140 Ve doe-2e: May 5| ¢ 42 || 47 eAcpr nes le doses i 9 46 | 15 | Mar. 25 |.s/d0-.--. - Se) 41 |j 48 Aes do = |--ndow ee Q 46 16 | Mar. 26}|May 8]{ ¢o 42 |i 49 | Apr. 8 | May 22] ¢ 44 i7 | sMar... 28; |==sdo.._- - So 41 50 sd@.22|5--@O=- oe 2 as 1805S Oke see May 9 Q 42 51 | Apr. 9} May 21 Q 42 19 }...do ; May TONES 43 Das OO | May 22}; Q 43 20° [422002 | May 6 Ss 39 53: h/2=d0z<2- 2 May 18 roi 39 21 SSC Oss | May 11 rol 44 5 54 | Apr. 10 | May 22 oh 42 |} 22 ..do..._.| May -10 JS 43 Do | EA pro els |S" dow. Ss 41 23° \-Mar. 29 May 11 2) 43 |i 56 | Apr. 16 | May 26 3S 40 | DAE MeO ast May 10 2 42 |} Diab | Ss3d0 se 2 May 23] ¢ Sine 2a )22200!: |e doses: Q 43 GS: | ee (ES May 30 oS 44 | 26 .do.....| May 12 Q | 44 59 | Apr. 18 | May 26 S 33 | 27 | Mar. 30| May 13| 9 45° il) 4 60 es does. May 28] Q 40 | 28 |...do.-...| May 15 Q 46 61 | Apr. 20} May 29 i) 39 29 | Mar. 31 | May 13| ¢ 43 62 \aApr 1217): der. | fe) 38 | 50 be dou. May 16/ © 46 | 63 | Apr. 22| May 30| ¢ 38 | Stalks sdoie >. |aidore-| Q 46 | 64 | Apr. 23; June 1| ¢ 39 | 52 eGdo |- do. 2:5 -|'549 46 | 65)e15= dose S|" dere Ss 39 33 2d052.”|e:4doles=: Q | 46 >) 66 | May 11 |, June ll} ¢ 31 \ | } Table XXX shows the variations in the length of the pupal period for 156 individuals as recorded in Tables XXVIII and XXIX: TaBLE XXX.—Spring brood of pupx. Variation in the length of the pupal period as recorded in Tables X XVIII and X XIX. Pupe. Days. Pupe. Days. Pupe. Days. Pup2. Days. 1 30 3 37 24 42 || 6 47 1 31 9 38 28 43 1 48 1 33 6 39 23 t4 2 49 2 35 6 40 12 45 1 56 5 36 12 41 13 46 Tables XXVIII and XXIX show that individuals which pupated early usually remained longer in the pupal state than those which later became pupe. Temperature conditions—The temperature conditions influencing the pupal periods of the spring brood of pupe are shown in the follow- ing table: s CODLING MOTH IN SANTA CLARA VALLEY. 147 TaBLeE XXXI.—Temperature conditions influencirg the pupal period of the spring brood in degrees Fahrenheit. Departure Month. Maximum. | Minimum. Mean. from normal. Chis te) he Sul. Mik ieee eel 63.3 46.0 54.6 +0.9 WAG Tle aed pe ei =) 65.0 42.7 53.8 —2.5 IMigryeten ene cones (at 69.2 43.8 56.5 =4°2 Average....-.---.- 65.8 44.2 55.0 SPRING BROOD OF MOTHS. Time of emergence of ,moths in the spring..—Figure 33 shows eraphically the time of emergence and the relative abundance of moths of the spring brood with the corresponding daily mean tempera- ture in degrees Fahrenheit. The records for these observations are given in Table XXXII. TaBLeE XX XII.—Hmergence of spring moths, 1911, from wintering material collected on banded trees during 1910. Number Number Number Number | Date. of Date. of Date. of Date. Oi ve moths. moths. moths. motis. | Mar. 24 1 Apr. 16 b May 9 9 June 1 6 Mar. 25 0 Apr. 17 Hike May 10 22 June 2 i Mar. 26 1 Apr. 18 12 May 11 32 June 3 6 Mar. 27 0 Apr. 19 11 May 12 23 June 4 6 Mar. 28 0 Apr. 20 33 May 13 20 June 5 0 Mar. 29 0 Apr. 21 26 May 14 18 June 6 2 Mar. 30 0 Apr. 22 11 May 15 PA June 7 3 Mar. 31 0 Apr. 23 28 May 16 33 June 8 4 Apr. 1 2 Apr. 24 8 May 17 15' i) Tune: 49 4 Agprs 2 0 Apr. 25 10 May 18 15 June 10 2 Apr. 3 0 Apr. 26 3 May 19 12 June 11 2 Apr. 4 1 Apr. 27 1 May 20 32 June 12 1 Apr. 5 1 Apr. 28 10 May 21 40 June 13 2 Apr. 6 3 Apr. 29 30 May 22 17 June 14 0 Apr. 7 1 Apr. 30 4 May 23 24 June 15 1 Apr. 8 1 May 1 10 May 24 1 June 16 0 Apr. “9 0 May 2 22 May 25 5 June 17 1 Apr. 10 0 May 3 7 May 26 15 June 18 0 Apr. 11 2 May 4 20 May 27 2 June 19 0 Apr. 12 2 May 5 6 May 28 2 June 20 1 Apr. 13 0 May 6 15 May 29 9 Apr. 14 5 May 7 6 May 30 9 Apr. 15 13 May 8 11 May 31 8 The rise in temperature on March 27 seems to have started a few moths to emergence while the later rise on April 13 brought out a large number of adults, and it was at this time that the first abso- lute maximum occurred. From this time on to May 20 the temper- ature remained little changed, but on that date it rose and seemingly occasioned the second absolute maximum emergence, which occurred the next day. By May 28 emergence was on the wane and the tem- perature had little or nothing to do with emergence following. The majority of moths issued between April 20 and May 23, a maximum period of 33 days. The total period extended from March 24 to June 20, or 89 days. 148 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. Time of emergence of moths vn the spring versus the time wintering larvee leave the fruit the year before.-—ULarve were collected from beneath burlap bands weekly from June 6 to August 22, 1910, and each weekly lot was assigned to a separate jar. Records were then kept of the moths emerging from these jars for first-brood adults of 1910 and those which wintered over as larve for spring-brood moths in 1911. The material collected June 20 was, unfortunately, used for another purpose and so is excluded in these records. Table XX XIII indicates the daily emergence from each jar and the dates when collections were made. The percentages of adults issuing from each jar in 1910 and 1911 and the totals for both years are also given. It will be observed that the moths of the earlier collections mostly issued in 1910 as first-brood adults, while those of the later collec- tions mostly wintered over to emerge as overwintering adults. Of all larvee and pupe collected only 53.7 per cent issued as adults. Of these the ratio of those emerging in 1910 to those emerging in 1911 was as 33 to 20, roughly speaking. Of the whole number of individuals collected 33.4 per cent issued as adults in 1910 and 20.3 per cent in 1911. The time of collection of larve in the summer had no influence on the time of emergence of adults the following spring. TasBLE XX XIII.—Adult emergence of the first and second broods from band material col- lected in 1909. Number : Dae collected— Emergence— Jar No. | collection. | Total: a ek eee | Larve.) Pupe. | 1910 1911 1910+1911 | | | = 1910 | No. | Peret No. | Perct No. | Perct C- 1 June 6 | 22 (a) | 28 Ose 2O 8 28 C22 June 13 22 Le) 77 32 41.5 0 0 32 41.5 | C- 4 June 27 Sia OM eel73 68 39.3 33 19.1 101 58. 4 C- 5 July 4 114 3 117 AD | SoOrO 34 29 79 67.5 | C- 6 July 11 326 28 354 123 34. 7 78 DP, 201 56. 7 C- 7 July 18 203 13 216 80 37 32 14.8 112 51.8 C- 8 July 25 102 9 111 PBS tk AAV 7 22 19.8 45 40.5- | C- 9 Aug. 1 Al 5 46 12 26.1 16 34. 7 28 60.8 | C-10 Aug. 8 18 1 19 0 Uf |e atoers Uf 36.8 | C-l1l1, Aug. 15 13 5 18 2 ital a 38.9 9 50 | C-12 Aug. 27 20 0 20 1 5 10 50 11 | 5d | Total.| 1,108 71 1,179 394 33.4 239 20.3 633 53.7 } Time during the day when moths emerged.—Observations on 100 moths were taken to determine what time of the day emergence was most common. Jars in which pupe for emergence were kept were examined four times a day for 14 days. The times of examination were 9 a.m., 11 a.m. 1p.m., and 4p.m. Out of the 100 moths only 9 issued between 4 p. m. and 9 a. m., 44 emerged between 9 a. m. and 11 a. m., 42 between 11 a. m. and 1 p. m., and the remaining 5 between 1 p.m. and 4 p.m. Thus it seems that from 9 a. m. until 1 p. m. is the customary time of emergence. (See Table XXXIV.) , C©ODLING MOTH IN- SANTA CLARA VALLEY. 149 TaBLE XXXIV.—Spring brood of moths. Time during the day when moths emerged. | Number emerging before— | | Total Date. emer- Jasme | ehiiacm™=. jlap2m:. 4p.m. | Bone | iss Apr. 26...| 21) 0 0 0 | 2 Apr. 28 Om 1 3 ay 4 7 Apr. 29...| Te 11 12 0 24 May 1 | a 3 er) om 5 May 2..-.| 0 12 5 1 18 May 3 | 1 4 1 0 6 May 4 0 6 4 0 10 May 6 Ons 0 6 0 6 May 8 i 0 2 0 3 May 9 ea 1 2 0 4 May 10 1 3 2 0 6 May 11 0 3 3 0 6 May 12 0 | 0 1 ihord 1 May 15...| 0 | 0 1 0 | 1 | | j | Total. , 9 | 44 42 San 100 } I Period of oviposition.—Although moths were placed in an oviposi- tion cage with apples as soon as they emerged, no eggs were observed until June 1. After that time there was no difficulty in obtaining egos. In the field eggs occurred early in April. No eggs could be obtained from single pairs of spring-brood moths, and thus no data were obtained as to the number of eggs a single female could deposit. In April and May, 1911, the mean temperature was considerably below normal and possibly this fact may account for the moths refusing to oviposit on the apples. From June 2 to 9 maximum oviposition took place. Longevity of spring brood of moths——Records were kept relative to the length of life of 40 moths which were placed in two jars and which were fed on grape juice and brown sugar. The results of these observations are given in Table XXXV and the summary of the results in Table XXXVI. TasLE XXXV.—Spring brood of moths, 1911. Length of life of the moths. Cage A. Cage B. Date of— | | Date of— Number | Number of Days. of a | Days. moths. Emer- moths. mer- : | gence. | Death. | | gence Death. } eueian 2 | Apr. 29....| May 1..-.. 2 DA Mays | May 4..... 1 ate GW eneal) NEN Ze ooce 3 Zi | eeeeedOs. alu Mayoous = 4- 2 Bad || (Berea doves: Maiygsenes 4 1s Rene dos==5 le Miaiva Gon == 4 Te | feat GOsssee May 4...-.- 5) aes |e doze | May 10. 7 (lea 1) See domnes Maio seo 6 ARES. dom22: | May 12.... 9 lo eee dora. May 7.. 8 Diane aie doze. | May 13.... 10 ihe | esate dos--2- | May 8...-- 9 jhe) sence does: | May 14..-- 11 ke) |e dos =--|) May:9ss2—— 10 A ee do | May 12 13 17 44 ge eee do Fic. 34.—Diagram showing first-brood pupe, 1911. (Original.) period of 68 days. The shortest pupal stage was 18 days, the longest 37, and the average 23.12 days. Using this average we find that probably the earliest pupa occurred July 4, and as the latest adult (see adult emergence record, Table XLIII) issued September 29 we have a theoretical range for the pupal period of 87 days. Of the larve under observation there were 21 males and 33 females, the average pupal stage of the former being 22.95 days and that of the latter 23.45 (see Table XLI), the females thus requiring half a day longer to develop into adults. Five individuals escaped before their sex could be determined. Figure 34 shows graphically the time of pupation of the first brood. CODLING MOTH IN SANTA CLARA VALLEY. 153 TABLE XL.—First-brood pupx: Length of the pupal period from material collected in 1911 on banded trees. \| [FE | Date of— | Date of— No. of Length || No. of Length indi- poe of pupal} indi- pono of pupal vidual. | Pupa- Emer- ‘| period. || vidual. | Pupa- Emer- ‘| period. tion. gence. tion. gence. Days Days 1| July 8) July 27 Q 19 Sie dale 207) Aue sel 3h eee 24 2 do. dO Q 19 32 | July 21 |} Aug. 11 Q 21 3 | July 9 do Q 18 33 .do.. Aug. 12 Q 22 4| July 10) July 31 Q 21 34 | July 22} Aug. 17 3 26 5 | July, 127|.22do- Q I) 350| July 24, | Aue 4a ee: 21 6 Gone PAE. ll oS 20 36 | July 25 | Aug. 17 oh 23 U Necc@@scisicllsesOe eh 20 Bi lee aloy Ome Q 23 8 doses |Esdor Q 20 38 | July 26 | Aug. 19 Q 24 9 domes |= 22do Q 20 39 doz.) Augs 20). 9 25 10 GOs AI oe Dates 21 40 | July 29 | Aug. 21 Q 23 11 GCOeee | PAt eS Q 22 41 | July 30) Aug. 23} Q 24 12 HOO Aug. 6 Q 25 AD ACO heres Pee o 24 ISG eolye eos PAU eel oes 19 43 |...do Aug. 28| 3 29 (45 | eno see HEA San v3) 21 44 | July 31! Aug. 24 Q 24 15 | July 14 |...do 3 20 45 | Aug. 1] Aug. 26 Q 25 16 Se SCOSS a 5lleaeCXo) 3 20 AGS | HendOnn. o| AUs. 27 Q 26 1 diwlhy IG Nee eC se sallacasos 19 47 dose aizscdoys 26 18 COs Sal AWB ees 21 48 | Aug. 2 | Aug 26 é 24 a 19 |...do.. Pb Fees (ii een 23 49 | Aug. 3] Aug. 30} 9 27 20| July 16) Aug. 6] ¢ 21 50 |...do..-.| Sept. 9 Q 37 21 do.. Aug. 19| ¢ 34 51 | Aug. 4 | Aug. 28 Q 24 22 | July 17 | Aug. 5 Q 19 52s =e done == mATIOS 298 lrg 25 PE 6 COSes cll ANUS 7 Q 21 GB) eecCO SS elas A000) Q 25 24| July 18) Aug. 8| ¢ 21 BE ee OO. Aug. 31 Q 27 My == Cs 5 2\) Aubkes D Ne ve 22 55 | Aug. 6] Sept. 2 2 27 2D Naas Os seal JNbIgS G3 Q 22 56 | Aug. 12 | Sept. 7| o 26 27 | July 19} Aug. 9 Q 21 57 | Aug. 13 | Sept. 2) ¢ 20 2835|=2 200s al eA eS 14 Q 26 58 | Aug. 16 | Sept. 13 fe) 28 29 | July 20 | Aug. 11 rot 22 59 | Aug. 19 fo) Pe es 25 SO) ssaG@s Savalas Abel ee 23 The variations in the length of the pupal stage are shown in Table XLI and a summary of Table XL in Table XLII. TaBLE XLI.—First-brood pupx: Variations in the length of the pupal period for 59 individuals. Pupe. Days. Pupe. Days. | | 1 18 6 25 6 19 5 26 7 20 | 3 27 10 21 1 28 5 22 || 1 29 5 DB) || 1 34 fs 7 24 1 37 TaBLE XLII.—First-brood pupx: Summary of Table XL. | Days : | in the Observations. pupal stage. INYO OG 5 aabodec 23.12 Maximum....... 37 Minimums =... —- 18 154 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. FIRST BROOD OF MOTHS. Time of emergence.—On July 22 the first moths emerged from band material collected July 6. The emergence reached its maximum August 19 and continued on until September 29. Most of the moths, @ oo as vy) 2c —_ ie) 2 S xX v Oo € J Ze 13 16 (9 22 25 28 15 18 21 24 27 _— September poyvadyej-ounjeuadwiay Aprep abeuany Fic. 35.—Diagram showing emergence of first-brood moths, 1911. (Original.) however, emerged in August and the first few days in September. As can be seen from figure 35 and Table XLITI the emergence is drawn out so that it covers a period of 70 days: TaBLeE XLIII.—Emergence of moths of the first brood: Material from banded trees. Date of | Number || Date of | Number Date of | Number || Date of | Number emergence. | of moths. || emergence. | of moths.}|| emergence. | of moths. || emergence. | of moths. July 22 2 Aug. 11 2 Aug. 25 3 Sept 9 4 July 25 1 Aug. 12 4 Aug. 26 5 Sept. 10 3 July 27 3 Aug. 13 5 Aug, 27 3 Sept. 12 ibs July 30 3 Aug. 14 7 Aug. 28 2 Sept. 13 2 July 31 2 Aug. 15 3 Aug. 29 6 Sept. 14 1 Aug. 1 5 Aug. 16 2 Aug. 30 9 Sept. 16 if AIS 2 1 Aug. 17 9 Aug. 31 1 Sept. 20 2 Aug. 3 1 Aug. 18 5 Sept. 1 3 Sept. 22 1 Aug. 5 3 Aug, 19 12 Sept. 2 4 Sept. 29 1 Aug. 6 2 Aug. 20 8 Sept. 4 1 Aug. 7 2 Aug. 21 9 Sept. 5 3 157 Aug. 8 6 Aug. 22 6 Sept. 6 1 Aug. 9 4 Aug. 23 6 Sept. 7 3 Aug. 10 4 Aug. 24 5 Sept. 8 1 Oviposition period.—Nearly all of the moths which emerged were utilized for securing eggs by confining them in Riley cages in which apples had been suspended on strings. The moths oviposited readily and a large number of eggs were secured. The first eggs were ob- tained on August 10, or 19 days after the first moths emerged, which was on July 22. The earliest moths did not oviposit in the cages but it is probable eggs were present in the field about the middle of July. The oviposition period continued throughout August and September. f. _were reared from the egg to ascertain the complete life cycle. CODLING MOTH IN SANTA CLARA VALLEY. 155 LIFE CYCLE OF FIRST GENERATION. Along with other rearing experiments to obtain the length of the egg stage and the feeding periods of the larve a number of adults In this experiment only six individuals were carried through the entire period and the details of the work are shown in Table XLIV. Table XLV is a summary of Table XLIV and shows that the aver- age life cycle from egg to egg (allowing 3 days after the moths emerge before eggs are laid) was 71.3 days, the maximum 77 days and the minimum 67 days. Adding the average egg stage, or 12.77 days, the average feeding period, or 25.08 days, the average post-larval stage, or 9 days, the average pupal stage, or 23.12 days, and allowing 3 days for eggs to be deposited after the moths emerge, a total of 72.95 days is obtained, or very close to the average life cycle, from actual rearing experiments. TaBLE XLIV.—Life cycle of the first generation. Date of— Length No. of individual. Sex. - Hidet: i of egg eposi- Heit ack arva stage. tion Red ring. spot. | hatching. Days. I es ei Sir slr been toee Corto oe ne gee re 3o& | June 2] June 5| June 15| June 17 15 Tih a Paola eee Sapte See aad Ran OF RR yY | June 8| June 10} June 18 | June 19 11 oS a Sa SOE ee oe oe es eee on aes Se eae oh a00)=- June 11 |...do. do 11 Ae Saree oa Seg SE eG Se Se ee eae Q “OW sseolesc do = Edo: do 11 LSS ah os Oe a a ic on a Se & | June 10 | June 12 | June 19 | June 20 10 Bap Se ae ae are Dies aoe aia ere re aie eee eRe GO} June 18 | June 26 | June 28 12 | { Date of— | Length | Total Length Emer- Length | oe ouput of No. of individual. iho Para of larval | gence of | of pupal Esost) | Bi ae > : = | Pupa- | stage. adult. stage. 88 8&8 entering | leaving | tion adult. egg. apple. apple. % Days. Days Days. Days. | le eee Sate) = pe ete eee at June 17 | July 12 | July 13 26 | Aug. 5 64 67 Pca pe Sto 8 ren er Beaters June 19 | July 17 | July 26 37 | Aug. 17 22 | 70 73 a beg tate Rae | ee TO. 2 5 al eames July 23 34 | Aug. 13 21 66 89 IE RRR ed ah yy = ea SO do. July 13 | July 31 42 | Aug. 21 21 | 74 77 De es Seo phen, ee = June 20} July 17 | July 27 37 | Aug. 18 | 22 | 69 a2 De crys a = Senate ee June 28 | July 23 | July 30 32 | Aug. 22 23 | _ 67 70 TaBLE XLV.—Summary of Table X LIV. | Total life | Total life |eycle. Egg|cycle. Egg | toadult. | toegg. Observation. Days. Days JARVCTAP CSS sna e eee ee 68.3 71.3 Miaxamiuirm ae ee ae seer 74 77 METI eee oe, 64 67 56602°—Bull. 115 pt 3—13-—4 156 - DECIDUOUS FRUIT INSECTS AND INSECTICIDES. SECOND GENERATION. SECOND BROOD OF EGGS. Incubation period.—In all, 845 eggs were deposited during the 33 days on apples in the cages used for this purpose. No record was kept as to how many eggs a single female deposited, but, judging from the number of female moths confined and the eggs deposited by them, the average for each female must have been about 40. No record was kept as to the time of day the females selected for ovipo- sition, but observation throughout the day showed moths ovipositing from early in the morning until evening. Table XLVI shows the length of the egg stage for 760 individuals. Taste XLVI.—Second-brood eggs. Incubation period of eggs laid in the rearing cages. | | Red ring. Black spot. Hatched. No. of | Num: | Date of | Length apple. pee e i | Gopal Date of | Num-| Date of | Num-| Dateof | Num- of 88 jeeese * | appear- | ber of | appear- | ber of | appear- | ber of | S48 ance. eggs. ance. eggs. | ance. eggs. | a, SSS] ———— | | Days. 1 3 | vAUg. 0) |e Sasa soe ese Aug. 21 3 Rees 23 3 | 13 Aug. 27 1 11 2 9 | Aug. 16 | Aug. 19 9 Hwee a 8 Aug. 28 Gi 12 8: Aug. 29 1 13 Aug. 28 6 11 Mae oF Pr | eeClansce 39 ||Aug. 29 23 12 4 46 | Aug. 17 Wie 1 4 Aug. 27 3 |; Aug. 30 9 13 ety Aug. 28 3 |{Aug. 31 2. 14 Sept. 1 1 15 SS ster sue Re Nap fee eae | = OI. te Aug. 26 3 6 4 |...do..... jus 20 ieee ee : \. do nee 3] oie One ‘fAug. 30 3 12 8 14 | Aug. 18 |,Aug. 21 5 |rAug. 28 LON ae | {ane 5S ; g Aug. 31 4 13 9 2 @Oz=ea Aug. 21 1 | Aug. 27 1} Aug. 29 i 11 10 1 |22do Esse ies 1 | Aug. 28 1 | Aug. 30 1 12 Aug. 29 5 11 3 Aug. 20 5 | Aug. 27 6 |} Aug. 30 15 12 a 25 | Aug. 28 age 21 16 | Aug. 28 19 |)Aug. 31 2| 13 Sept. 1 1 14 12 2 Anos St ee dOneee 2 dos 2| Aug. 30 2 12 NaN Aug. 31 1 12 13 4| Aug. 19 | Aug. 22 { Sept. 1 ig aR AS barat Aug. 30 2 \\Sept. 2 2) ate 14 9 |...do.....| Aug. 21 6 | Aug. 28 Sead Pa leaees 15 3 | d ICG aan 1B Loe (ee ee 2| Aug. 30 i 11 Sl WERCSS Aug. 22 1 | Aug. 29 1| Ang. 31 2 12 | Aug. 30 ie eae | lfAug. 21 1 Aug. 31 2 12 ie 6 |---do....- Va 22 3 \aug 25 5 Sept. 1 | Hi niin Sept. 2 | i} 14 — Aug. 29 2| Sept. 1 1 13 1 4 |---do.....)-.------2-[-2-2---- ee 30 1| Sept. 2 | 1 14 18 | 4] Aug. 20 ce 22 S \. do ce 4| Sept. 1 Aalto Aug. 31 1 11 Aug. 22 6 | Aug. 29 5 19 11 {twigs am ‘i Sept. 1. g| 12 | Aug. 23 2 Aug. 30 5 {sev 2 | 1 13 = Aug. 29 3} Aug. 31 1 11 20 11 |...do....- Aug. 22 9 \iue: 30 4| Sept. 1 g| 12 aL | iliea (eae a ee 14 | Aug. 29 11 | Aug. 31 | 2 11 ol abo ec Aug. 23 1 | Aug. 30 | 4| Sept. 1 12 12 29 Ble does -.|os.doeee 2} Aug. 29 2 nD | Pine | | [2] 3) ua las | ces 28 2| Aug. 31 ohne a | Aug. 23 2 Sept. 1 | 6 11 24) 20'|-=-d0-----\\ Nnig, 24 14 |}--do..-.- ue Sept. 2g) = | | \|fAug. 23 1 ept. 1 | 5 25 | 16 |...do..... Were 24 u } -d0....- 16 hSept. 2 | relies mae | CODLING MOTH IN SANTA CLARA VALLEY. ee 5 Vi TaBLeE XLVI.—Second-brood eggs. Incubation period of eggs laid in the rearing cages—Continued. Red ring. Black spot. | Hatched. Noes Num- | Date of Num- | Date of | Num- | Date of | Num- | 0! €88 ber of | deposi- apple. F Date of C888. OIE: appear- | ber of | appear- | ber of | appear- | ber of stage ance. eggs. ance. eggs. | ance. eggs. Days. ifSept. 1 1 11 26 7 | Aug. 21 | Aug. 24 4) Aug. 31 6 | Bet 2 3 12 \{Sept. 4 1 14 Sept. 1 S 11 28 f2)|eoodose- (on 5 \ doze: 12 {Seon 2 7 12 ; \[Sept. 3 1 13 Aug. 24 8 ifSept. 1 3 11 29 20 |.--do..... ape 25 7 \ -do..... 18 | Sept. 2 15 12 30 25 | Aug. 22 |...d fag ee - {sent ae alt a = Aug OSsese iS, epee Te ept. 3 22 12 eee s s Sept. 4 rie 73 31 6 do... do...=. 6 Sept. i 5 jSept. 3 6 12 ug. 31 1 | Sept. 2 1 11 32 2 fps Cl cee LOS t 3 Sept. 1 2| Sept. 3 Belk tact y - |{Sept. 2 5 Ii ae dOzceo: 5, Aug. 31 7 33 13 |..-do-.... parte 26 2| Sept. 1 5 {sept J alte Aug. 31 1 | Sept. 2 1 11 34 S))-=-dor—- ae 2 7 Sept. J 7 | Sept. 3 7\- 12 seGW)sso55 3 | Aug. 3 20 | Sept. 2 il 11 35 24 |...do..... ee 26 3 | Sept. 1 4} Sept. 3 13| 12 36 5 | Auge 23;|--.do..... 3 \eepe ; fil eedosees Bele eet 37 Aaa dOssee= HE eaaes Doe sO eeace 4 sane 4 4 aC OR=ne= 2 2 38 adores es ] \ does. 7 Sept. 3 4] 18 ms ept. 4 Aug. 26 Ave t OOsses- 5 | Sept. 4 3 12 39 11 |...do..... ‘Aug, 28 1| Sept. 3 1 | Sept. 5 3 | 13 40 14 SOW soaks ug. 26 9 6 2 14 Bet: 4 14 12 O82 4A GOee ae 2 12 41 6 |...do ies 4 {Sent 3 1 | Sept. 5 al ae i S Sept. 4 1 | Sept. 6 1 ie ug. 26 16 | Sept. 2 25 | Sept. 4 18 42 27 |-.-do....- ‘Aug. 28 4| Sept. 3 2 | Sept. 5 7) 2B Aug. 27 16f|Ssndowss.. Dall [nea eee , 43 29 | Aug. 24 = > \\Sept. 6 21 13 ane 28 7 | Sept. 5 3 Sere 8 1 15 Sept. 3 17 | Sept. 5 9 12 44 19 dos2se- Aug. 27 | 18 |{Sept. 4 1 | Sept. 6 8 13 : Sept. 5 1 | Sept. 7 2 (Sept. 5 14 Sept. 3 | 23 | 45 Dag eeedoss=3|-. do. -.- 19 {ee Jsept. 6 Sh eta pt. 4 2} Se < pt. 7 25| eee 46 Tile doe: edge: 6 | Sept. 3 10 | ae z ae 47 20 |...do..... douse: 17.1) .do..... 20 epee oles 48 40 | Aug. 25 | Aug. 28 | 27 out : = | Bent u a a Sept. 4 33 | Sept. 7 33 13 49 SGs seed One a= GOokeere 29 Se pt. 35 3 | Sept. 8 2 14 Sept. 7 20 | 13 50 Dislus dos 22 Bdow:. 18 | Sept. 4 21 Sept. i pale sin 51 Ag\pedoess= Sidoes-- 35s a dosaae 3 | Sept: 7 3 | - Sept. 4 | Sept. 5 52 3) ee 3(6 Ose dow: Ihe = al | ay PAM eene oo 3 senna | anil an = Dee de cOy) Aue: {Sept. 6 12 | Sept. 9 Dale sid 54 A Wee OM aacee Sato 5G60 3 | Sept. g gent: 8 3 13 55 93 |:..do_-.-- dou 20 Sent 2 i \. do AE 22] 13 Sept. 5 9 | 56 17 AO seece RdOesees 11 {sent 6 G | a0 Sate 16 13 Sept. 7 Sept. 5 3 SE(8 Weeder 8 13 57 9 ..do S00 .do posoc ( {Sen S 1 bse 9 1 14 Bauler 204) 2do..2s.|.-4dos.- 16 HSePt 8] ap fsept. 8| 19 | 13 (Sept. 7 q ts 4d0-22-6 7 \}Sept. 8 59 17 | Aug. 27 | Aug. 31 11 {Sept 5 se 9 8 13 i\(Sept. 10 2 | 14 158 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaBLE XLVI.—Second-brood eggs. Incubation period of eggs laid in the rearing cages—Continued. . | Red ring. Black spot. | Hatched. | No. of | Num: | Date of | — | rr apple. ets pean - Dateof | Num-! Dateof Num-/ Dateof | Num- wee | le Geesay "| appear- ber of | appear- ber of | appear- | ber of | S'#8® | | ance. | eggs. ance. eggs. ance. eggs. | fee | | | Days. | | | Sept. 6 2| Sept. 8 oh ise: 60 9 | Aug. 27 | Aug. 31 | 8 Sept. 7 6 | Sept. 9 Bre ets | |Sept. 8 1 | Sept. 10 1 let 61 2)| Seedokes |b does 1 | Sept. 7 1 | Sept. 9 (Mal pale 62 3) |e doe =| Edo. ae 2| Sept. 6 2! Sept. 8 2) 12 Sept. 8 4 Na 63 7 | Aug. 28 | Sept. 1 bas | Sept. 9 2 eee Sola as | Sept. 11 fis) Pe Le 2 - |(Sept. 10 Le ibesd3 64 (AOE a eas AOS a 6 NeepE. 5 9 \Sept. 1 4 14 | | : Be: Sept. 12 Pll ee 5 | eento 1 sept. 9 ig ero 65 Belt adoneea| senda. se 5 \{Sept. 8 Bach | | Sept. 9 1 |fSept. 10 | Zonet | 2 : | Sept. 7 5 | | 66 eure aera 8HSeoL 3 Ber done |b 8+ eat te 67 | De PANIge 20-,2e Owes ee 2 race nde 2 | Sept. 11 2 izes a) el ae | fidosse Stee dooce 4 13. | 68 | ) ---do. --do..... | = HSept: 9 2 | Sept. 12 1 14 | 69 | Seed On aaa Ose ce 3 se 8 3 | Sept. 11 3 | 13 i Oa Rea een poy|eeee 2 !|Sept. 13 al ame mo] 5 |tue 9 feooe ns] aia | aR] 3] fs aot wane nO. o see 1 | Sept. 10 1 | Sept. 13 1 13 ‘ Pl seepage Sept. 7 1 | Sept. 12 1 | Sept. 14 1 14 72 |} fA aso oes Sept. 4 it | Sedoses= i |e OO see 4 14 | 73 | pI Es 0 Kai a ene oe eae ales a] gence ee poke aes 2 NEE dOseecs 2 Va | 74 | 7| Sept. 1 eer ‘ 3 \sept 13 7 | Sept. 15 TA tea 4 Wen \jSept. 4 | 5 dosti. 15 14 | 2) ee as) {Sent. 7 hte \ do..... ar {sent 16 ro hemes 76 41 Sept. 3 |...do..... 4 | Sept. 15 4 | Sept. 17 4 14 | 77 16s|sSepurc ss ieesdos- Ae ab Sno el oe SSR CS Sept. 18 4 14 | 7 4 | Sept. 12 Sept. 22 4 | Sept. 25 4 13 | i From Table XLVI it will be seen that the average egg stage was 12.5 days, the later individuals remaining in the egg slightly longer than the earlier, a phenomenon probably due to the gradual lower- ing of the temperature. Out of 845 eges deposited, 760, or a frac- tion under 90 per cent, hatched. As can be seen from a study of Table XLVI the red ring is not a constant factor in the egg develop- ment, since it could be discovered in only 610 individuals. Mortality is about equally great before and after the appearance of the black spot. Table XLVII shows the variations in the length of the egg stage as recorded in Table XLVI. TaBLeE XLVII.—Second-brood eggs: Variations in the length of the egg stage as recorded : in Table XLVI. Number | scumb | Number | |, Number Batts of eggs | Days | of eggs Days | 68 | il | 8 15 301 | 12 | La 07, | 13 || 760 | 76 | | Table XLVIII is a summary of Table XLVI and shows the aver- age, maximum, and minimum length of the egg stage. CODLING MOTH IN SANTA CLARA VALLEY. 159 TaBLeE XLVIII.—Second-brood eggs: Summary of Table X LVI. | Length Observations. of the | egg stage. | Days he Asverages.sseraae IPA i} Maximum=s2...- 15 | Minimum..--.. 11 SECOND BROOD OF LARV. Time of hatching.—Eggs obtained in the cages hatched from early ~ August until September 25, but as the first moths did not oviposit in confinement just-hatched larve in numbers were probably in evi- dence in the field from the latter part of July until the middle of October, when most varieties of apples were picked. Feeding period.—Apples on which eggs had been laid were placed ‘in jelly glasses to obtain a record of the time taken by the larval development in the fruit. Although in most cases several larve entered the same fruit more than two full-grown larve never issued from the same fruit. The apples used were yellow Newtown Pip- pins and were large enough to provide food for several worms. The larvee have a habit of coming out of the apple, wandering around the class for a few days, and then entering the fruit again, thus extend- ing the period of their growth. This habit may account in part for the large variation in the length of the period between hatching and the final emergence from the fruit for the purpose of spinning the wintering cocoon. The maximum time spent in the fruit was 79 days and the minimum 43, with an average of 58.15 days. Table XLIX gives the record of the time spent in the fruit of 39 individuals. TABLE XLIX.—Second-brood larve: Time spent in the fruit. | | | | Larva | ne | Larva ee No. of | Larva emerged Days | Nese! rae | emerged Days = apple. | hatched. rom -, || apple. | hatched. rom a pp | fruit fruit. | erent fruit. = | 1 | 13 | Sept. 1 | Oct. 21 50. || 53 | Sept. 7| Nov. 22 76 28 | Sept. 2} Nov. 7 66 || 54 | Sept. 8 | Nov. 2 55 29d SIC Oe Ra Nov. .2 61 55 ar see Nov. 21 74 33.} Sept. 3 | Oct. 27 54 56 Soed Ofs=e4 | INOWe ao 58 340-2 -d0L-==: Nov. 1 59 Sie ee Oeaeee Nov. 26 79 35 | Sept. 2 | Oct. 22 50 59 | Sept. 9 | Nov. 13 65 36 | Sept. 3 | Nov. 12 70 60 | Sept. 8 | Oct. 23 45 36 | Sept. 4 | Oct. 20 46 60 | Sept. 10 | Nov. 24 75 37 | Sept. 3 | Oct. 22 49 61 | Sept. 9°} Oct. 27 48 40 | Sept. 5 | Oct. 20 45 Gi S5-Clascece Oct. 31 2 41 | Sept. 4) Nov. 4 61 62 | Sept. 8 | Nov. 15 68 42 | Sept. 5 dose 60 63 | Sept. 11 | Oct. 30 49 43°| Sept. 4] Nov. 3 60 645 | Eat Ose Noy. ll 61 45'| Sept. 6 | Oct. 14 43 65 | Sept. 10 | Nov. 1 52 AGH Rad Ones Nov. 5 60 69 | Sept. 11 | Nov. 5 55 47 | Sept. 5 | Nov. 14 70 75 | Sept. 15 | Nov. 2 48 49 | Sept. 6 | Oct. 19 43 75 ere See: Nos Fi 66 50 | Sept. 7 | Nov. 8 62 7 O2k-- Novy 58 Ole ex Gosee-= Oct. 31 54 7 doze. Nov. 9 5d G2 0 Oesece Nov. 12 66 | ! 160 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. Table L, a summary of Table XLIX, shows the average maximum and minimum time spent by the second-brood larve in feeding. Taste L.—Feeding period of second-brood larve: Summary of Table XLIX. eer Days in Observations. hetruit. AVCTARC: Ss ens. 58. 15 Maximum....... 79 Minimum! 22 see- 43 Time of leaving the fruit for wintering—Table XLIX shows that the date the earliest larve left the fruit was October 19, but as these larvee were not from the earliest eggs deposited and the earliest moths did not oviposit in confinement the band record will show when most of the larve cocooned for the winter. The band record for 1911 shows that after August 31 second-brood larve were un- doubtedly hibernating and that they reached their maximum from September 28 to October 5. The earliest second-brood larve prob- ably cocooned the latter part of August and since half-grown larve were found in apples on the tree as late as November 30, it is possible that the last stragglers did not cocoon until some time during Decem- ber, 1911, or January, 1912. NATURAL ENEMIES OF THE CODLING MOTH. Parasitic insects —The egg parasite Trichogramma pretiosa Riley may be regarded as a factor in the control of the codling moth in the Santa Clara Valley. In 1909 eggs of the host were collected to obtain records on the parasites. A large number of the Tricho- gramma issued, but as there was no record of the time when the eggs were laid by the moths or parasitized by the chalcidid, the life cycle of the parasite was not determined. In 1910 the Trichogramma was very abundant, so much so that in the life-history work on the codling moth the jelly glasses in the insectary containing the eggs had to be carefully covered to keep out the parasite. In this year a record was kept relative to the life cycle of the parasite. Table LI gives notes on the life history of eight parasites. Tasie L1I.—Life of Trichogramma pretiosa in codling-moth eggs. pave from Date para- | Date para- | deposition ) AG cei sitism site of eggs to * | observed. | emerged. | hatching | | of parasite. July 24 Aug. 5 Aug. 19 26 Cee os SAC Who oecoll ANUS A 27 July 27 Aug. 10 Aug. 23 Dil Smicne O.....-| Aug. 24 28 July 28 Aug. 5 Aug. 19 22 Ofeece douse se elies COPE GRO. 22 Aug. 1 Aug. 10 Aug. 22 21 Aug. 2 OMe Soaleee doe. 632 20 ——————— CODLING MOTH IN SANTA CLARA VALLEY, 161 The date on which the parasitism was observed can have little to do with the actual date of the parasitization of the egg. As the parasites were very abundant in the vicinity of the eggs it is prob- able that the latter were stung almost directly after being deposited; consequently the parasites’ life cycle would start immediately after the codling-moth eggs had been laid. Figured in this way the life cycle ranges from 20 to 28 days, with an average of 24.16 days. A comparison with the life cycle of the parasite in earlier or first-brood egos and in eggs of the second brood would be interesting. In 1909 several parasites were reared from the larve of the codling moth by Mr. J. R. Horton, of the Bureau of Entomology. These were all unidentified Hymenoptera. Toward the end of April, 1911, some overwintering full-fed codling moth larve were observed by the junior author to have a whitish, distended appearance and upon closer examination proved to have been killed by a hair worm, determined at the instance of Mr. A. L. Quaintance, of the Bureau of Entomology, by Dr. B. H. Ransom, of the Bureau of Animal Industry, as belonging to the family Mermithidz. These worms, of which there was one in each host, lay coiled up, occupying the entire interior of the larva and exceeding 3 inches in length when uncoiled. None was found in the larve of the first or in those of the second broods taken in 1911 from banded trees. ? Predaceous insects—In February, 1911, the larve, pupe, and adults of Melachius auritus Lec. were found in considerable numbers, apparently preying upon the larve of the coding moth. The speci- mens, on request of Prof. Quaintance, were later determined by Mr. E. A. Schwarz, of the Bureau of Entomology, who said in reference to them: ‘‘* * * This and other species of the same genus have repeatedly been reported to the Bureau of Entomology as enemies of the codling moth. The genus (excepting the imported Malachvus gzneus L.) does not occur in the Atlantic slope of North America.” BAND RECORDS OF 1909. Through the kindness of Mr. E. Northern, of San Jose, Cal., 20 trees of his orchard were banded to obtain records. The apples are of the Newtown Pippin variety, and the whole orchard, with the exception of the banded trees, is annually treated with several apph- cations of arsenate of lead. The bands were of burlap and were placed at an average of 30 inches from the ground after the loose bark had been scraped off. Asummary of all of the work performed, including the total number of larvee and pup (each collection), the weekly emergence of adults following, and the total number of larvee which transformed in 1909 and which hibernated until 1911, is shown in Table LILI. 162 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaBLE LII.—Band record for 1909. oO N ae LE Number of adults emerging from respective collections by—| o | Total age No. of | Date of |——_——_larvee ST RSS record. jeg teenies 3 | 3 pias NS | To ee Gaerne ic eg sist eer leege lee 7s | p | 8 |PUPR tT | ml ob | | | wr Le eI SIS IES So qs Shiller Ses 7s | Sa. Bee er io me 1 Sl/eB lala la l|/a}/a |ani|a\|niaio lI Meee June 21 |1,602 |215 | 1,817 |264 | 378 | 388 | 399 | 402 | 403 |....-|...-]..--|.._.]....1.--- 403 Deis June 28 |2,276 | 79 | 2.355 | 0 | 249 | 607 | 646 | 666 | 677 | 678 |.--.|----|....]...-]..-- 678 Bea Sie! July 6 946 }159 | 1,105} 0 OF 1661146287) 6905) $78) ): 722) Se Sa eee tee eee 722 gas eee July 9{ 804/93| 897 1 8 | 27 | 387 | 411 | 422 | 425 [426 |426 |427 |_...].... 427 Deel July 12) 761 | 59 820 | 0 3 8 | 159 | 270 | 291 | 294 |295 Sat taal Pog NR BS 2 295 Grates July.15 | 885 | 68 953 | 0 1 2 9 | 431 | 484 | 492 |495 |495 |496 |....]..-- 496 eee July 19} 919) 48 967 | 0 1 2 6 | 84] 391 | 418 |429 |4382 |432 |433 433 Soins July 22 | 536) 37 afd | 0 0 0 1 3 | 200 | 247 |258 |259 |260 |... .|.-.-- 260 Qe | July 26} 505 | 30) 535) O 0 0 1 2 | 8% | 185 1140146 |448 | 2-2] = se 148 LQ esse July 29] 350} 22 32 | 0 0 0 0 1 1| 66] 73} 76 | 78 | 79 79 Lika aes | Aug. 2] 297 | 22 319 | 0 0 () 0 0 2 12: 469/472 | 480 eS a4|e ee 48 Dee oe Aug. 5 180 | 16; 196] O 0 0 0 0 0 Oils 2: | 92,3] aa alee ol ee 4 1S a re Aug: 9 185 | 7, 192; 0 0 0 0 0 0 0} 4) 22 | 25] 26 26 | LE ESeee Aug. 12 115 | 10 125 | 0 0 Oule=20 0 0 1 Lee ease Oe 9 Leos Aug. 16; 112} 4 aL OG 0 oO; —0 0 0 OF OF 2) aba SISs arse ks UG. 3> =e Aug. 19; 262) 2) — 264) O 0 Daly -@ 0 0 0; O} O /103 |105 |..--|105 IW pene, Aug. 23 | 383] 0); 383] 0 0 OO 10 0 0 OOF SOR ale ar Sa eee als So ee ers Aug. 26| 403} 3; 406] 0 0 Oy ee 0 OP One Os OF 2 bye 19 ee eA. BH! ART | 4 AST) 10 0 Q/' 20 0 OF acON On| ht) a| a IPs Byala 6} Dons RST STS cp soos kal ar ae ah Pe er ot eae ot eel ennai acbbe lines aN) Fie Sept. 6| 580] 0. 580 ESR an ae abit Oe Ld & SED] Cee eri eres 0 DD Nee Sane SSRI Oh) ee kode Seis wedllo aes clsoee alten Se eerie eames (reese Merl Deere os 0 OB) A ene Sept. 13 | 253} 0 LOO i Weer een S| acer nee eel eae Payee eal aoe sp he Pet cae eee mee | aes 0 pyrite | SemeslG. |. 359) 4) ee S6Oul eee |e lene oe Mae [<3 Ne See uc aria al ae | ee ee eee pe 0 Dil aes: Sept. 20)| 2004-07" 2001/5 1Fi)e2 7 Ie SE an ee | Lea | et Ween area | 0 ! | 1 Records annulled through larve being arowned in winter. Figure 36 shows graphically the 1909 band record. BAND RECORDS OF 1910. | Total issued 1910. - . Through the kindness of Mr. W. J. Farrington 12 trees of his orchard at San Jose, Cal., were banded to obtain records of the second-brood larve. The apples were of the Skinner Seedling variety; and as this HE seer fit | 8 a. =) Oo 3 ¢ © 8 > < w =i) S mR Ny) x) £ 2 Ze ‘5 ib August Fic. 36.—Diagram showing band record of 1909. (Original.) ett IS September apple ripens early, no records could be taken after August 22, there- fore showing practically no second brood of larve. CODLING MOTH IN SANTA CLARA VALLEY. 163 A summary of all the work performed in 1910, including the date of collection, weekly emergence in 1910, and the totals for both 1910 and 1911, is shown in Table LIII. TaBLE LIII.—Band record for 1910 at San Jose, Cal. n ~ ” = Diemer ‘a, {Number of adults emerging from respective collections by— i iS « R cas) | No. of | Date of ' g = = a as | 24 record. |collecting. g 3 = Bix [oi sie] 4 oO asny iris || | Sia lhe = ® iS & aval [plead acyl eT STS rola | T=Ys) ats Veco ee nal i teal [aed eGo 3 Aes fois | a le is bo Soe ele) eS | ea bee es PSS So) es ee et Veet | See |e eo eae is Seo UU CMMOR M22 eOniee 20 lbeS, |e Oi cee| nce loteele we |e St Pe 8 0 hs oe CMe SS ee dOnt la lineal 26) 283-2001 20817 201 298 3B) | NS0T Sale Talos Aes 32 0 coy Te June 27 | 173} 0] 173} 0/| 50} 60] 62; 62| 62! 65! 66! 67 67 8] 68] 68 33 Bele Utes AT Sy 1 tg O) | 2 27.1331" 39) |" 4-1 43 43} 44] 45 45 45 34 Teesbee July 11 | 326} 28] 354] 0 1 | 5} 36) 95: | 143 | 117 |} 421 | 229-1 199°) 493). 3] 493 78 Geen se: July 18} 203 | 13] 216] 0]! Oo Ilene 1 12} 53 7 79 | 80] 80] 80}. 80 32 CiSoS eee July 25] 102} 9/111] 0} 0| O| O 0 2 14} 21 22 | 22) 23°) 23) 23 22 See ae AU ee eAleieeoe 46.1. Ol. 0 | 01! 0-1 (0 OF eae QE eal aller lesen | 12 16 Oe es Aug. 8 18 1 OF Os ONO Onl 50. 0 0 0 0 0 0 0 7 LOE Aug. 15 ISI ea) 1340) 0} 01) 0 teva) 0 0 OF =20 0 22 2 7 did beeen 3 Aug. 22 20; 0 20 0 ON220 Onlers0 OF SE0 0 0 0 1 1 1 10 1 The worms collected June 20 were used for individual pupation records and none of this lot was kept for overwintering emergence, so they are excluded from this table. Figure 37 shows graphically the 1910 band record. | BAND RECORDS OF 1911. Ten trees of the Newtown Pippin variety were selected in the orchard of Mr. E. Northern. These trees were banded June 1 with Fie. 37.—Diagram showing band record of 1910. (Original.) burlap bands of an average width of 8 inches. These trees were left unsprayed while the rest of the orchard was treated with arsenate of lead. aif 164 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaBLE LIV.—Band record for 10 apple trees at San Jose, Cal., 1911. Number -| Number Date of | oflarve Date of | oflarve | collection. and _|| collection. and | | pupe. | pupe. | \PediliysGenes) Ao |i ISOs eos! 23 July 13...) 91 || Sept. 14 43 July 20...) 84 Sept. 21 (3 | July 27 52 Sept. 28 82 Aug. 3 40 Oct 83 Aug. 10 38 Oct. 12. --| 64 Aug. 17 16 Aug. 24. 15 774 Aug. 31. 14 From this table and the accompanying diagram, figure 38, there can be observed two clearly defined broods, the first of which reached its maximum about July 16 and the second about October 1. After Re 2 =) io io [Pes w 8 > < i o aa is) Se Vv me) € >) ZE ee ee eee aera ee 14. Zl 28 5 12 September October Fic. 38.—Diagram showing band record, Northern orchard, 1911. (Original.) August 10 only two pupe were collected, so that it can be safely assumed that all the individuals taken after this date belonged to the second or overwintering brood. FIRST-BROOD EMERGENCE v. OVERWINTERING EMERGENCE, 1911. From band records collected in 1911 (see Table LIV) 774 larve and pup were taken. Some of these, from the first collections, were placed in vials for individual pupal records, while the remainder were placed in jars for adult emergence records. Those placed in the vials were all of the first-brood larve and only a very small percentage overwintered. The latter collections—both consisting of first-brood and second-brood larye—resulted in an emergence of first-brood moths of about 18 per cent. Only 157 moths emerged from these collections, although a considerable number of pup died in their CODLING MOTH IN SANTA CLARA VALLEY. 165 vials. Compared with seasons 1909-10 and 1910-11 this was a very small proportion of moths for the first brood as against those hiber- - nating as larve, for in both these seasons the advantage lay easily with the first brood. According to these data there appears to be an excellent reason to look for a large overwintering emergence in 1912. REVIEW OF LIFE-HISTORY WORK OF 1911. Similar records on the life history of the codling moth to those kept in 1910 were obtained in 1911. Theresults of these observations are shown in the diagram, figure 39. Spring pupe were present about February 20 and continued until June 20, reaching the maximum about April 12. Moths began to emerge about March 24 and con- tinued until June 8, with the maximum emergence occurring about May 8. Eggs of the first brood were deposited from March 24 until July 11, with the maximum deposition taking place about May 12, while the first-brood larve hatched from April 23 until July 26, with the maximum hatching period occurring about May 30. First- brood larve cocooned from May 25 until August 26, with the maxi- mum cocooning period about June 28. The first-brood pupz were present from June 30 until September 29, with a maximum period about July 28. First-brood moths began emerging July 17 and continued until September 29, the maximum emergence taking place August 16. Second-brood eggs were deposited from July 18 until October 4, with the maximum period about August 28, while the larve hatched between July 30 and October 18, with a maximum hatching about September 4. The second-brood larve began to cocoon August 14 and on throughout the winter, reaching their maximum about September 18. The overwintering part of the first-brood larve commenced to cocoon about June 12, but the majority of the over- wintering larve came from the second brood. The life cycle from the time the spring pupe appeared until the last first-brood larvee cocooned occupied a period of six months. COMPARISON OF LIFE HISTORY IN 1910 AND 1911. From a comparison of figures 31 and 39 it is apparent that the main difference exists in the fact that the 1911 season was about two weeks later all through. This is quite to be expected from the colder and later season of 1911. Table LV shows a comparison of the life histories and various stages of the codling moth in 1910 and 1911. 166 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaBLe LV.—Comparison of life history and stages of the codling moth for 1910 and 1911. First-brood larvze | | Spring pupe. |= irst-brood eggs. in fruit.1 Year. | | | | ‘Maxi-| Mini-|Av er- Maxi Mini- |Aver-| Maxi- Mini-| A ver-' Lvtaxei Mini-| A ver- gaan mum.) age. mum. speed age. mum. mum.) age. |MuM.mum.} age. aa ae Seaeee hanagrt aes oe eee ey ‘Days. Days.|Days. Days. Days. cea page Days.|Days.| Days.| Days.|Days. VDIQ As eC I ee ere ee 61 29 40.7 | 17} 8 |12.4 103 31 |48.8 55 11 | 19.04 TO eres 2 ee ae 56 30 OLIN 10 P 12.77 | 42 26 |34. 67 37 tSeh23-12 | | | | | Lifecycleeggtoegg. | Second-brood eggs. Secon eae larvee in Year. | Maxi- | Mini- te yet tle aan ied ef CODLING MOTH IN SANTA CLARA VALLEY. 167 ture for the growing season from February to October, inclusive, for the years 1909, 1910, and 1911; also the mean temperature for the month and the departure from normal. Table LVII is a summary of Table LVI and shows that in 1909 one month was normal, two were above normal, while the remaining six of the growing season were below normal. The total accumulated mean temperature for the 1909 growing season was 15.9° below the normal, giving an average monthly departure from the normal of —1.76°. The 1910 season shows four months above the normal and five below, with a total accumulated mean temperature for the growing season of 7.9 below normal, with an average monthly departure from the normal of —0.87°. The 1911 season shows one month above the normal and the remaining eight below,. with a total accumulated mean temperature of 23.7° below normal for the growing season, which gives an average monthly departure from normal of —2.63°. The 1910 season was much the warmest and 1911 unusually cold— so much so that most stone fruits did not sugar up well. The 1910 season, barring June, which was very cold, was practically a normal growing season. Looking at the three seasons from a meteorological point of view, one should expect to find the largest percentage of the first-brood larve transforming in 1910, with a large second brood indicated by the band record, while 1911 should give the smallest percentage of transforming first-brood larve, with a smaller second brood 4ndi- cated by the band record. The 1909 season should have given a larger percentage of transforming first-brood larve than 1911 but less than 1910 and a larger second brood than the 1911 and a smaller one than the 1910 season. Just what did happen is given under that paragraph comparing the seasonal history of the three years. TaBLe LVI.—Daily mean temperature for the years 1909, 1910, and 1911 at San Jose, Cal. Date. 1909 1910) 5|22/1914 Date. | 1909 1910 1911 | | poe. | | CAH Se Oe a ana ah fe Beach eAH °F | Feb. 1 56 42 | pave teatte bilge oas | 52 46 a4 Esl 58 43 | 56 19. 48 49 48 | Baas | 50 41 | 50 20 Ea 47 | 48 46 oes 48 43 | 52 7A se 49 48 48 | DE ea 47 44 52 222. 48 50 48 | 6 47 t4 46 23. - 52 | 58 48 | eae 46 50 44 24S 50 | 56 50 | Bare 46 48 47 ee 48 | 50 44 Cer 46 52 46 ZOnsee = | 50 | 50 43 NO 47 50 49 | Diioas | 49 40 | 11 04 49 48 285 sae a2 | 58 42 | 1s eae 52 51 | 47 | | | 1B eee D1 | 56 44 Total av-| 50.6 | 48.7 46.9 | 1 eee 50 | 46 40 | Departure USecose 58 46° 40 from nor- | Wie see 60 48 41 | mal for | 1 aoe 54 48 | 46 | month...| Normal. —1.9 | —3.7 168 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TaBLe LVI.—Daily mean temperature for the years 1909, 1910, and 1911 at San Jose, Cal.—Continued. Date. 1909 1910 ot Date. 1909 1910 1911 oH: nfs ae Oe Oe: 70 CoHe Mar lessee 54 60 44 Wii tess. 67 51 53 Drs 54 61 47 | 2 eF 60 56 59 Sens 58 60 53 Sees 60 52 54 ADEA 47 54 49 4f Ls 59 52 58 Sener 47 52 Dae eee 58 58 54 6.253% 50 52 Ril 62555 62 59 54 fans 50 54 52 7 (aera 60 63 51 Brae 50 54 57 822552 56 60 54 ee 52 60 50 Ore: 54 65 56 1eesas 54 58 50 LOS Sze 53 60 56 1b 53 60 51 i eee 53 60 57 ie eee 50 52 54 iZieeee 56 60 56 1Bossee 50 55 56 ieSeess 58 58 52 1 ses 52 58 58 iV eS 58 64 56 1G Se8 50 57 58 Gees S 53 70 54 1G aeeee 50 62 54 NG ssde 52 Tal 54 Wiese 50 62 53 iW (see 53 64 56 18s 52 56 57 1 52 62 56 iLO eae 48 54 56 AGS ee: 56 62 59 PAN Soap 46 56 52 20556 53 62 67 PALS uee 45 52 53 PA es 50 58 68 2a 47 54 55 225aE 52 63 63 2B ono, 50 48 56 RYO 52 63 56 DALE 48 48 58 Py 58 62 52 ARLES oe 52 52 oil RR oe 60 64 54 26 eee 50 50 53 265 ee 60 65 53 Dy ati 48 46 58 If xe 56 62 58 DR eee 50 52 60 ZSusr te 55 64 58 PA Se 48 54 65. | 20 Wares 60 72 56 30. - 48 58 66 30s 64 78 58 sles 53 60 61 SI eae 70 72 62 Total av. 50.5 55.3 54.6 Total ay . Otee 62.3 56.5 Departure || Departure from nor- | from nor- mal for mal for month —3.2 +1.6 +0.9 month —3.5 +1.6 —4.2 ADT esas: 56 58 56 Tunewsleees 63 65 60 De fxd% 60 53 56 Ae Bs 63 62 62 32 55 56 52 Bisse 60 58 62 - Ari 3 47 58 56 yes 58 58 60 ie Baar 52 56 60 | Lite. Ss 56 54 61 GAs 54 56 54 | 622 64 54 60 BRE oe 58 52 51 (ares 62 57 60 8.. 60 56 56 Brae. 58 64 58 ee a 64 56 54 One ee 66 72 62 10 bes 54 56 50 Owe 63 62 64 ibibo oe 54 52 49 | Vn RE RE 60 62 67 1 ee 58 56 45 ipy ea. S 57 61 60 1B 56. 58 56 48 | ees. 52 54 60 Tos = 62 58 52 | ik ~.5 3 56 57 61 1 ee 64 62 56 | ie 8 66 58 64 1652 62 62 56 GES 60 58 64 Lee 58 62 66 60 1 /eeee 56 56 65 1a ee 51 59 53 SS 57 55 68 AQUS AS 50 60 56 OE re 60 58 64 WIE Se oe 52 58 56 2) Sees 62 56 62 PAE ee 2s 54 61 56 PARES 63 56 55 DD Rsk 56 66 57 Doe a 70 56 54 PResane 57 72 57 23 ee 78 62 58 DAE 59 68 57 24. 68 65 58 DIN Aas 2 58 58 58 PASS Os 8 65 70 61 26 eee 62 Ey 50 265ee 64 64 70 Ifo a = 56 54 308 | Py fae 59 60 62 28 Soe 56 53 Some ZB soe 58 58 60 Ze 59 53 50 | AAD kes 56 59 58 30 Seer 64 54 50 | 30 62 62 64 Total av. 57.1 58.1 po. | Total av . 61.4 59.8 61.5 Departure '|| Departure from nor- | from nor- mal for mal for month... +0.5 +1.5 —2.8 month... —3.6 —5.2 —3.5 7 CODLING MOTH IN SANTA CLARA VALLEY, 169 Tasie LVI.—Daily mean temperature for the years 1909, 1910, and 1911 at San Jose, Cal.—Continued. Departure | from nor- mal for month... Totalav . Departure from nor- mal for month... 1910 1911 i Date. | 1909 | | OIDs Septal 64 PRE 62 322 64 4e33 64 ee 62 6s< 64 ron 63 8.. 68 Ques 69 1Oe= 63 fafa 67 12e= 70 18%. 70 lige 72 ae 74 UGS. 73 ities 65 Soe 64 19_. 62 20s S 62 PALS 66 22s 68 23-2 62 DA 64 PT ete 59 DAR Rie 64 PA jee. 63 PAS ae 62 29_. 60 30 56 Total av . 64.8 Departure from nor- mal for month... +0.1 OctAy lesa 54 7} Se eae 60 Oo 56 4 ee 60 Taner 62 (Ti Bs 60 eee 60 Sees: 64 OF ss 68 {Ones 70 pe 66 TQ 62 13ese2 60 - 4 61 eae: 54 Ge: 56 1 Eg =e 58 HS eee 56 Or 61 205 64 PAE re 60 Oe 59 OE veces ae 62 Pleo 64 PA ee 62 PA eae 56 Disk 54 Daten: 54 PAS Ves 51 30! 50 Ble 52 Total av .- 59.3 Departure from nor- mal for month... —1.0 1910 [sss ea bea baahcecedin 1 ierettie d icawiaaee —1.3 170 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. TasLeE LVII.— Bee ee ee eee eee Normal = a9 wee ce Mariel 3 os, See Re ee ES Oe ieee een eee a 29 +1.6 ate ert April 2 ss 2 2S See es ny a ee ee ae + .5 +1.5 ee May 2 Bois be eo Be eS ABE Sore Ae ee ne oe — 3.5 +1.6 = 28 tt ae ee ee = | eesti Spee rey Ce ee Ro - al ase Mop. = — 3.6 —5.2 Eas pat UG aoa = Sonsas8s eo: Sese5528=5- ee ee ee eee — 3.1 —1.4 = Tei) AMSUSE Sse 525 es ee ee SS a ee ae ee OS a ee RR aco eee — 2.1 —2.3 SE: Heplem bers. 250) sae = 2-8 ee ree oe ee oe eee Oe 2 ie Sa | eg a a7. OGTO DOT eS eh he eae el 2h By dee eter ee Sea — k.0 9 = Te Otal 255 5--S8s se Sea es os Sa eae ee eee ee eS —15.9 —7.9 —23.7 Average monthly departure from normal. -.-....---.-----.--------- = 76 = 37 TOG COMPARATIVE LIFE-HISTORY STUDIES FOR THE SEASON OF 1909, 1910, AND 1911. The temperature conditions (see Table LVI) indicated that 1910 was a very warm season favorable for the development of the codling moth, while the 1911 season was very cold and unfavorable to this insect, with 1909 an intermediate season. The 1910 season, while apparently very warm, was a more normal season than the other two. On account of many lacking life-history records in 1909 but with a good band record, and a poor band record in 1910 but with com- plete life-history records, it is impossible to make perfect comparisons of the three seasons. An examination of both band records and rearing experiments shows the following data, however. (See Table LVIIE.) TasLe LVIII.—Summary of the band records for 1909, 1910, and 1911 along with rear- ing results, showing the comparative size of the broods and relative number of trans- forming and wintering larve. Percentages for— Larval collections. 1909 1910 | 1911 ; | | Transforming larve—total band collection..........-.---.-.------------- 27.6 | (4) 18.0 Winter's laryce—total band collection es ==... oss eee 72.4 | (4) 82.0 Relative proporiiow of first-brood larycess 2s. -2 = = eee = eee 95.0 | 2+50.0 50.0 Relative proportion of second-brood larvée----.-.-..-----=----------------- 5.0 2 +50.0 50.0 ibransionnrn ¢ lanycoonnrst DIGOG).2= See oees nn eee ee eee 33.5 | 33.4 40.0 Winterine larvetofirst broods: 2: 3-.22222 22> .)s ee ee | 66.5 | 66. 6 60. 0 1 Band record from summer apples. 2 Approximately (from rearing records). The results as indicated by Table LVIII are not entirely in con- formity with expectations. The relative proportions for the broods for 1909 and 1910 appear correct in comparison with the weather conditions, but the relative proportions for 1911 seem incorrect after examining the weather condi- sseacaegties o) CODLING MOTH IN SANTA CLARA VALLEY. lye tions for that year. Theoretically, on account of the very cold season there should have been a large first brood and a small second brood, which is further borne out by the small percentage of transforming larvee of the total band collection. One fact is evident, however, there were more codling-moth larve present in the field in 1909 and 1910, which gave a larger series in the band records for these years in comparison with 1911. The 1911 season was apparently so cold early that moths did not Oviposit properly and the temperature conditions probably exerted such an influence that the infestation was light, therefore cutting down both broods and making them nearly equal. CONTROL OF THE CODLING MOTH ON PEARS AND APPLES IN THE SANTA CLARA VALLEY. While prunes, apricots, and cherries are the chief fruits raised in this valley, there are about 500 acres set to apples and 1,400 acres to pears. These orchards on the whole have probably paid better financially the past five years than many orchards of the first three varieties of fruits. Situated’ as they are, on the lower and wet but rich soils near Alviso, they have escaped the attacks of the chief insect pest to deciduous fruits in central California, the pear thrips (Huthrips pyri Daniel). The codling moth, aside from several species of plant-lice, has been practically the only insect worthy of the atten- tion of apple and pear growers in the Santa Clara Valley. : It is needless to say that spraying, both good and bad, has been practiced for the codling moth, but the majority of the fruit growers have either sprayed at the wrong time or in an indifferent manner or have used ineffective poisons. The writers have seen apple orchards that had been sprayed three times during the season and these had from 75 to 80 per cent wormy fruit. Until the past two or three years there was a tendency to do slipshod work at low pressure, and even now many growers try to use too many leads of hose and to cover more trees with too little material. The practice of using four lines of hose on one spray outfit should be discouraged since it is difficult to maintain a suffi- ciently high pressure and the nozzle men frequently interfere with one another. It would be much better business to use more spray outfits, and even to spray from a tower. Data are presented here from one apple orchard and one pear orchard where the spraying was done after the directions of this bureau. On both orchards the work was in the nature of a commer- cial demonstration and it is in a way unfortunate that no checks could be obtained on the pear orchard, which was sprayed two suc- cessive years, although the early history of the place is known. 56602°—Bull. 115, pt. 3—13-——5 72 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. THE O'TOOLE PEAR ORCHARD AT ALVISO, CAL. This orchard hes on a road intersecting the Alviso and Milpitas Roads about 6 miles north of San Jose and is, strictly speaking, in the Alviso section of the Santa Clara Valley. The soil is entirely “made soil,” the orchard itself being surrounded by a high levee. The type of soil is a very rich sandy loam styled ‘‘Fresno sandy foam’’ on the map by the United States Geological Survey. This orchard, 30 acres in extent, is composed of six varieties of pears and the trees are some of the finest in the State of California, many of them reaching a diameter of 8 to 10 inches at the base. Durmg the years 1910 and 1911 the writers have, through the courtesy of Mr. George Reed, manager of this orchard for the Ander- son Fruit Co., been able to obtain figures on the wormy and non- wormy fruit. Mr. Reed, in talking with the authors, stated that the orchard usually contained from 15 tc 60 per cent wormy fruit before it was placed in his hands, even when sprayed for the codling moth. The early Bartlett pears were seldom extremely wormy, but late varieties, such as the Winter Nelis and Easter Beurré, frequently had more wormy pears than clean ones. One peculiar fact relating to this orchard should be mentioned here. The west and north sides are closed in by a levee of the Coyote Creek, which is about 10 feet high. This has caused the orchard to blossom and mature its fruit about 10 days earlier than other orchards in the vicinity and has therefore made earlier spraying necessary also. Spraying operations ——A power outfit was used both years at a high pressure and arsenate of lead as a poison at the rate of 2 pounds to 50 gallons of water. An old spraying outfit was used in 1910 and a new one in 1911; consequently much better work was done in the latter year. In all of the spraying large-chamber nozzles were used, one to each spray rod. All of the work was done from the ground, the men using i2-foot rods and 50-foot lengths of hose. Since no check on the spraying was left, no figures are presented here on the cost of spraying and the benefit derived, but a summary is given of the wormy and sound fruit of the trees examined under each variety. Season of 1910.—The fallen fruit was collected under five trees weekly throughout the season and examined for the entrance place of the worms on each of the six varieties. (See Table LIX.) 173 88 'F 18° GIS | SI6‘T | #8 Tés‘t | 66¢‘T | 0 6 g ial gsg‘T | 9T8 z Ch | «9% OL OF “poulqulod g-] Sealy, 89% g" 00°% | 200‘T | 92 186 106 0 0 g g £06 O0T 0 OMe \eer £2 LUC NBS 6 serene ae a 12) 0 9F 9 69°T | €8°ST | 98 &% EE 9% 0 P 0 P EZ ZI 0 Geer. 61 TO Temes! ec ie Serene °Z GOL], PE '9 €o°T | LT°6% | 2g¢ gg LG Och 0 g (4 L 6FP 96 j LT |6 82 amen nee oe I OO e Neos I1v[O Fa 29'S L¥'T 8S°LT | Ih‘9 | 89T Gro‘9 | 8c6‘s | ¢ cr | CIP 88 048‘¢ | S¢P g re =| &P 08 CLE “ poul Wood Gf soody, ie $81 Ie" 9'2L | FS0'T | FT OF0'T | 96, 0 g 0 ¢ $96 18 0 L 7 II ( asiorene ace atesaae Sad is =-5cioolt, =e eONG VoiGue | MeONOGe licecek eco (2 U A STON 10) PA | At 9 680‘T | P21 j ie It 9¢ Sgt eee p OO, > 09% VOT | PL | 196 | 92 0867) S16 1.2 g Or GT 006 | 9F 0 V 9 OL Soe aa eee eC """8 901]; 08 ‘T 66T |! 848 | GILT | 18 889'T | 919'T | @ Of. M0 rae P6S"T | SOT I 7 7 6 76t Ue ee ee Z SOL, a 8h 'Z €9°T | LL | Lh T | 98 TIL |128b 0 He (82 a6 ogs‘T | S6 0 9 8 FI Lake ie Seka "TOOL, a eh ie ‘Hole. Es ONG LorGe =|) €E5G; = |)96Ger-- 1 96 TEMr =| Toles |G [ieee LY 09 199° | SOS‘T | T Ven |2O% cg OLP‘T | pourquioo ¢-T soody, a 89% 08°S | 7h:G. | Z80-T +) 62 €c0‘T: | &TZ 0 € LT 02 £69 69 0 L j 6 OOS csctil ese sens eae “¢ Gol, H 86% 61'S | 90°F | 1F6 8Z £16 G6G 0 T €1 ial T8¢ OFS I 6 7 cal COG ae Ieee ea ee "bool J, 7 60'8 29°F =| OOT | OFS 8T 8E9 OPE I 4 iat OT 0ge 00% 0 1 1 z S6l8. Rar ear Aces € OOL], zi) 8 OL" GL: sel LbG | 78% 0 0 6 z 8 LOG 0 if I z Sy Alm igi re ge “"% O0L,], w vPr't COTE |j2F Ge | 90Te Te | OT 060‘T | €82 T § f 8 GLL 88 0 9 (6 8 fy ema ag ORR cages G9 T 00]; SOOTULOL) a Se Le LA kL Sas | ees eeees | peireegeeeeeensenee | ‘ ‘ ‘ ‘ . ‘ ene | an 16 °6 £86 19'OT | Soho | PFS T16"h | ZhL°S | 6% THT | 98 992 98h '% | SIL'S | FE O9T | F6 886 GCP SG poulqurLoo G=T seo], | KH ee a | ee a ae ; i hs 4 fet aor Se EES 2 eS Stamateer ~ a — —— =) LE 6 666 oP 6 8éL i £91 GLO T | 688 IT bP 82 £8 908 68 8 3 6£ 08 GOL» [oF Se eee ““¢ 001, fate LZ 'F1 6L ‘FT | C8 FL | 4ZT T | 89T 600'T | 98F v 68 92 69 LIP 169 8 99 G 66 COGS elie: eee ee aa “p OOLT, Fy 826 £8 60°01 =| 12g €¢ 81g G9Z L 6 9 (46 £06 908 g LI 6 T¢ GUCR ARE Lae Ss eee eres “"¢ OOLL, é ‘ LT 6 86 828 661° T | OL 680°T | FOL 9 oP 1% 69 Ge9 G6b 6 9% 9 IP 4 ee OMe ete OS G 991], is 6b 9 92 °¢ 066 OLL 0¢ OL 868 I L g I G8 OLE v 8T GT LE Oe iB: ae aaa are ear a I 991, | (>) = —_ oe — = = — ——— acanonsaan = —ee | ioe - + —- _ —- aie 3 "WAI | OPIS | “xATBD ‘ "W9}S | “Opis | “xXATBD = ; 001) | *puUNoIs SO TVover eda laa Ns Ie dee MESS a bean) “AULIOM) 1, a: aaa *AULIOM ey saute 7. UO | -gmay |-hva0m| SUM De RPA ONS |e eel ees) AONt cal ee d “| Surtom | AULLOM i a J aia ou poo} Wo SULIOM OLOU] A. *polo} WO SULIOM O10 MA “901} JOON A fejo,z, |OB8H99 | o8eyU90 TBE LUDO UA revO Tales tee Weal) Geen ae ey |e cathe. Sota Sy SS ne “Od “LO 7 "9014 WO VINYL ‘urddrgy unojmany ‘fijow04 ‘TI6L fo wosnas “ST[RJPULM. 2 ATOL ONV 6 ANOL ‘6 AVW GAAVUdS ‘pLDYILO § UMOYILON “OT “apy ‘8ajgddpv wo you burppoo sof burtinads fo synsayy— TXT ATAV YL, ee EEE CODLING MOTH IN SANTA CLARA VALLEY. 179 The five sprayed trees under observation show a range in wormy fruit from 6.49 to 14.27 per cent, with an average of 9.97 per cent, while the five unsprayed trees ranged from 45.28 to 82.16 per cent wormy fruit. The five sprayed trees averaged 90.03 per cent sound fruit, while the checks averaged only 25.45 per cent sound fruit, the spraying thus giving a benefit of 64.58 per cent sound fruit on the sprayed trees. It is evident that the second brood of larve caused a large per- centage of wormy fruit both on the sprayed and unsprayed trees. The wormy fruit on the five sprayed trees at picking time ranged from 14.19 per cent, and since most of the apples affected by the first brood had fallen off before this nearly all of the injury can be charged to the second-brood larvee. CONCLUSIONS FROM EXPERIMENTS IN CONTROL. Two orchards, one of pears and one of apples, which had been - sprayed for the codling moth according to the recommendation of this bureau, show conclusively the advantage derived from this treatment. The pear orchard shows more decided results than the apple orchard because of more thorough work with a power outfit at high pressure. The second year’s treatment on the pear orchard shows to advan- tage because of better work and timing of the applications. Two years’ observations have shown that three applications of arsenate of lead in the Santa Clara Valley at about 2 pounds to 50 gallons are necessary for pears and apples, except on Bartlett pears, where two would be sufficient. The first application should be made just after the blossom petals fall, and the date may vary from early April to the first few days in May, depending upon the variety of fruit and the season; the second application should be made about from 2 to 3 weeks after the first application, and usually falls in June; the third application should be applied about from 3 to 4 weeks after the second, and usually falls in July. Arsenate of lead can be used on pears along with the treatment recommended for pear-thrips larve, and the distillate-oil emulsion seems to give the poison a smoother surface tension so that it spreads more readily on the foliage and holds up longer in suspension while in the spray tank. The arsenate of lead should be mixed separately and added last to the spray tank after the distillate-oil emulsion and tobacco extract have been combined. 180 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. A power outfit should be used in spraying, maintaining 200 pounds pressure. Bordeaux nozzles equipped with an angle and used from a tower give the highest percentage of clean fruit. SUMMARY. In the Santa Clara Valley of California there occurs one full gen- eration and one partial generation of the codling-moth larve. The following is a brief summary of the life cycle: The overwintered larvee pupate from the middle of February until May, the moths issuing about six weeks later through a period extending from the latter part of March until the middle of June. Eggs are deposited about 3 days after emergence, and these hatch in about 12 days, the red ring appearing in 2 or 3 days and the black spot some 8 days later. The first-brood larve enter the fruit shortly after hatching and remain there for about 5 weeks. They are present in the fruit from the last week in April until the last week in July, a range of 3 months, or nearly three times their average larval life. After leaving the fruit the full-grown larva seeks some crevice in the bark on the main trunk or on the larger limbs of the tree and there spins its cocoon, transforming after a few days into a pupa. In confinement a great variation occurs in the time between spinning the cocoon and actual pupation, but in the field there is probably not nearly such a variation. The first-brood pupal stage averages 21 days, only half as long as the corresponding stage of the spring brood, a fact due, undoubtedly, to the considerably higher temperature influencing the former brood of pupe. First-brood pupe are present from about the middle of June until the middle of September, although the two years 1910 and 1911 (see figs. 31 and 39) show a considerable diver- sity on this point; for in 1910, the warmer of the two years, the first- brood pup were present three weeks earlier. Similarly the first- brood moths emerged just so much earlier in 1910. A fair proportion of the first-brood pup overwinter, and for this reason some individ- uals remain in the immature forms for 10 or 11 months. The first- brood moths begin to deposit eggs 3 days after issuing, and these egos hatch in 11 days, or if the season is cold in 12 or 138 days. The red circle and black spot appear as in the first-brood eggs. The second-brood larvee remain in the fruit about 50 days, and they are present from the latter half of July until the middle of October, a period of about 80 days, and thus shorter in comparison to the length of the larval stage than in the first-brood larve. This is accounted for by the shorter period of adult emergence, causing a shorter period of egg deposition in the first-brood moths as compared with that of the spring-brood moths. All larvee of the second brood winter over and form the great bulk of overwintering larve. Doubtless if the CODLING MOTH IN SANTA CLARA VALLEY. 181 fruit remained longer on the tree there would be a complete second brood possible, since so many varieties of apples and pears are picked before the end of September. In 1909 the second generation exceeded the first and this was a cold year, while in 1910 and 1911 the two generations were about equal in numbers, in spite of the fact that the former was a warm, the latter a cold, year. In 1910 there was good reason to expect a large second generation, considerably greater in relation to the first generation than in 1911, but the relative proportions of the two generations was not maintained in 1910. Consequently it may be wnferred that the weather does not always exert great influence on the relative sizes of the two generations any more than a large number of individuals of the first brood does on the second. The relative number of larve of the first brood that overwinter varies from year to year, but not entirely owing to influence exerted by the weather or the temperature. The larve of the second brood are present in all but the earliest varieties of fruit, and it is necessary to combat them. Weather conditions exert more influence on the spring emergence of moths than on the summer emergence. The sex of the moth can be determined in the larval stage by the _ presence or absence of the two testes, which are black and in the male show through the skin on the dorsum of the eighth segment. Three applications of the poison spray are necessary for the control of the codling moth in this locality. The first should be made imme- diately after the petals have dropped from the blossoms, the second should follow from 2 to 4 weeks later, and the third a month or 6 weeks after the second. ee COPIES of this publication may be procured from the SUPERINTEND- ENT OF DOCUMENTS, Government Printing Office, Washington, D. C., at 10 cents per copy INDEX. Arsenate of lead— Page. ADAMS AC OGMENE MNO Ghietssra 5/5 Srps to oho ci cya S ste iol Soe aisle bas 172-180 and Bordeaux mixture against codling moth, plum curculio, and apple SCAND E 5 SLE ee hs Oe ee te erg ee nd Bee Ree er Se ek ae 94-98, 104-107 and lime-sulphur, commercial, against codling moth and plum curculio.. 89-112 and lime-sulphur, home-boiled, against codling moth and plum curculio.. 93-98 distillate-oil emulsion, and tobacco extract against codling moth and pear INSU SEPM nt Maras a) Mt oy alm atid ac Ale Mair as Mera We( or a cee 179-180 Ascogaster carpocapsx, parasite of codling moth................-..-..-.- 6, 74-76, 86 Bordeaux mixture— FCN SVE SE Dy OLS SCE Oras ene tle SES ree NEL eer eh ae SRT eae? PRR 94 and arsenate of lead against apple scab, codling moth, and plum curcu- Roe Sse a ea acer ere ee mnt Ur Lenn Amu) 94-98, 104-107 Carpocapsa pomonella. (See Codling moth.) Chelonus carpocapsx. (See Ascogaster carpocaps2.) Chiisopa spe enemy-oL. cod ling moths ost. 3 oc) ebb Ue Ue oo on eee 74 Codling moth in Michigan— |S@NIWG! TROCIOING IS! CHR IC OS ae ara epee ag ey eV ac ae nee ute Wee ec 5-6 | SVEGYOl TRECLOTAGISY OVE TID ces ee ane ENS eC agate nengRaIES Sg ape RISO Gg Pa 2 26-31 bandsrecords(or Olek oes set La easy Cee Nie EME SSM RS rate Le, 60-65 Cambie alasmba MON SalanviEe eCopt aoe is Sean Se ante See yoke kee ae 83 COCOOneOlananteriNnolapvase st Jie Lo 2a osc SO So ceo icteet ee ee ee 6-7 life-history studies for the seasons of 1909, 1910, and 1911, comparison..... 70-73 deumitioneoigtenmicsuseatt in lie aes iss Soe. Ue ele gs ones 2-3 first-brood eggs, effect of temperature on time of incubation.........-..-- 44-45 frst-progoserosmencth Of McubaAtiON..5..0.-- 2. 3 -t ee see eee oe 14, 42-44 EST -rOOUslanvcs larvadeliie IN COCOON. 2. ..5- 255/22 aso 5- 8 -se se 15-16, 47 first-brood larve, length of feeding period... SEES hha ee eal AG first-brood larve, percentage of those sanefinaahae and aineeeiae Ai ae ae 15, 47 fireiaMrood. lame etamMe: Ofhatching— fs. oe. to. Ss ois slate sot =e 14-15, 46 first-brood Lae AATHS (OMIM ATUTLEY = <1 io ie PR at hal oo ang eee 15, 47 first-brood moths, egg deposition by individual moths. .........-....--.- 19-20 MEK OnCodemMotaslenotiy ollie: . 2500. Case. se tte Sec lds eae oe 20-21, 52-53 frSt-prood mothentime of emergence... 22 =. .-1-4- 2/22 S20 Soo io 4,18, 50-51 fest-prood moths. time of oviposition.: —. 2. .26)--\ 2 -.-/22 3-2-2 5-a 18-19, 51-52 irs soompi pee senoth Of SlaLe) = 4.402 5. 24.sb tebe te oS. Sy eens 17, 49 PEE DrOOG Dupe «tne Of PUPAtION = 00 eee e as oa Sy. keene sf 17, 48-49 SNS: SRO eRe Ge are eee eM e lege) or Ieee ermal 14-23, 42-59 SRSVeN VEeAVGUIE SNES Oe EA em eae Pe OL en NEE a mils ANN a Sm ONE JE 73-76 Paeciccamoyomapple«oliagess .. 4.220 joes bee epee ls oe 84 Jarvee remaining two seasons in larval stage.......2....-----------+-+---- 83-84 lowealeunatarsrand smolts. niumiber-s20 yoo. eke ole. tyesinrk Homo atiey e rele 76-83 iieteveleoitrst Seneration.§.... 2362 ./2% 2) 2+) bela Se ease yee 21-23, 53-55 MaPseerOMeCOUSODSErVALIONS) 2 = 45202 Sa. Soi asics 5 = na 3 srelelchayS aeni etm, paler nl 76-84 poison spray applications, time to apply them.............-------------- 86 75716—Bull. 115—15——2 183 184 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. Codling moth in Michigan—Continued. Page. rearing material, soureees.. 2 = <.50 2 5-. 2. See eee ee ee ee 33 seasonal-history studies of 1909.2 .."2 2.252 {2222s Se oe eee 3-6 seasonal-history stidies of 1910-- -- <0. fo ach ee oo ee ee 6-31 seasonal-history studies of 1911). 2.25.32 ee ee 32-66 second-brood eggs, effect of temperature on time of incubation..........- 58 second-brood eggs, length of incubation.............---...---...--- 23-24, 55-58 second-brood larve, length of feeding period....-..............-....---- 25, 60 second-brood larvee, time of hatching................--.-.-----.-.- 24-25, 58-60 second-brood larvee, time of leaving fruit... ..--................----.---- 25, 60 Beconmipenbratin*. 22.3 SL Se a eee 23-25, 55-60 spring-brood moths, egg deposition by individual moths...............- 3840 spring-brood moths, egg deposition in stock-jar experiments..........-. 40-41 Bprink-prood moths, fencth of hie’. 2-2 2 iT eee 13, 41-42 spring-brood moths, period of egg deposition. ...............--....------ 41 spring-brood moths, time of emergence... -...........-...----- eee aa el Na sprins-brood moths, time-of ovipogition =o) = 222 2. en oe eee 12-13 sprins-brood moths, variation im size. . <2. -2 J<2.< 2 ee il spring-brood pups, length of pupal oth eee Me eee spring-brood pupz, methods of recording a 1, SUG 1 SS eaehre Dae a spring-brood pupz, relation of temperature to feeeee ol singe:: 25a 30-37 spring-brood pupz, time of pupation ..~ . 2". 205.22. eee 9, 34 simimary,wenerals — 0.200 OSE ee ee eee 84-86 summary of seasonal-history studies of 1910. _...........-.......--.----- 31 summary of seasonal-history studies of 1911 -_.................-.-..2-.--: 65-66 weather records for’ 1909; 1910; and 1904: 2.5 1) 2 3 eee 66-7 MATICTING Linyie: = S0 S Sloe e haere sae see ae i cA ie SE 6-8 wien larvse, cocoa: * 25 Psi. S2io22 sees: stl ese eee 6-7 wintenny lirves:, yaration in sive 52555222522. esr ee eS ee eee 7 winter iciled daryse.| 2 22 t-k Vet te ake eee t eee eee noe oe 7-8, 33-34 Codling moth in Santa Clara Valley of Cahfornia— band Tecords'of 190922222" 2-202 2-22: 22th Per: Lees ee ee 161-162 Gand records of 10. S25 oo. Srl 2 ee eee 162-163 band records of 49112 = os 82 52 te eee .. 163-164 comparative life-history studies for 1909, 1910, and 1911...._....._._... 170-171 . comparison of life history in 1910 and 1911. _--.-.--....-.-..--.------ 165-166 control on ‘pears and apples.) 2222 222-7222. > Se eee 171-180 ditsb-DtOOd Cogs.) | Os DELP leche thst Cea 115 first-brood eggs, incubation period... ..........---.---------- "126-1: 28, 150-151 first-brood emergence v. overwintering emergence. -........--.-----.---- 164-165 first-brood ‘larvee = <5 2222 9222222 Loe ee eee 115 fst-brood larvz, larval ffiem cocoon. _ 22 =. eee 129-130 first-brood larve, number developing in one apple. -.-. --.....-.-..-. 128,151 first-brood larvee, period of feeding 1 fruit: <2) = Yee eee 128-129 fast-brood lary, time of hatching: : :-.c 3 Ye Ee eee 128, 151 first-brood moths, oviposition period 2. =... 2222225. 52.522-0 eee 134, 154 first-brood moths, time of emergence. -......-.------------ 117-118, 133-134, 154 first-brood ‘pupee 25s 2352 oss Soe eee eee 115-117 firsi-brood pape, Jenpth of stages. 3222 2 2 Lat eee 130-133 first-brood pup, time of pupation - - 223! .22 5222 82 ee eee 130, 152-153 hist venermtaon 2. VSS he es eek eee oes eee 115-118, 126-135, 150-155 ie cycle of first peneration] <2: 62222922. 22t2 ee eee 134-135, 155 natural enemaes.* 532 414) ee PS ee ee ee eee 160-161 review of life-history work of 1910... _..:_....-.¢+22s22.20ht ee 142-143 ee ee INDEX. 185 Codling moth in Santa Clara Valley of California—Continued. Page. Fae Gite IMELorypWwOEk OF 191M: 0s ee ee ee yee 165 BEasOtel METRY SLUGIeSs Gil QUOl 04. kame mr eo fs ee a ee 114-118 SEP SUNT ie VS GTA 7 SAG Re Seto) BR OL aR 2 ee 119-143 ReAnOma Minima SEOs OFT OTT 28 Ue Ma tg a 8 143-160 BECOME EMOMEC ORR street ea! is Se gee ere i A ng ot aba OR eae 118 second-brood eggs, incubation period:...................-.--- 135-140, 156-159 second-prood larves, feeding period. . . s 2.22 2.2.02... 2.22. 140-141, 159-160 Seeene-pmoduaryer. tmelor hatching. > 22: 20h ees es Va 159 second-brood larve, time of leaving Bees for wintenng.-M-.22 23.0 141-142, 160 BEPOnMECOHeIhIOM ane eae fl POS es Pe ee 118, 135-142, 156-160 NC EAMMIBCTIOM OLN EEN EG Joy So) 02s 22 Fh Sh Do 2 eR oh eee 143-146 BREN roOd MONE Meme ts 2260. S. hscae o oS oo Sabeeee Be ee 115 spring-brood moths, longevity..-..-.-....... OE etn BA I, SC es agli 149-150 spring-brood moths, period of oviposition. _...................---- 125-126, 149 spring-brood moths, relative percentage of larve wintering from band material and percentage emerging as first-brood moths the year larve MELEE DHE CLOOu esas ayn setae Sotto Bead stkit igo ys sereinsage eee ee 124-125 spring-brood moths, time of day moths emerged..........---------- 125, 148-149 spring-brood moths, time of emergence....-.......---------------- 122-123, 147 spring-brood moths, time of emergence versus time wintering larve leave EQUOTe TED eCCCSG NUT /E S057 Tr cae eR ree ge Se 123-124, 148 S/S EDGES NRE OG | (OUT Ee Sem EE er lye cS Cle 114 spring-brood pup, comparative length ot pupal periods of male and female Ee ER ee ei a ke oe ee ee See owe = eee 122 spring-brood pup, length of spring pupal stage...........----.------- 120-122 Spee nrood pupe: dime ol pupation. 2s... 2.25. --25 ln b eae ena 119, 148 peer Ey ena cane ee Sa eee 180-181 temperature conditions for spring brood of pupe, 1911-...........----.--- 146-147 weather records for 1909, 1910, and 1911.............---- ip A a eae 166-170 Codling moth, one-spray method in control— POE PET CINE 2 SS GR a Ng ae te 110-112 experiments in Delaware......-. EA OME R NE PMA bs 5 Rome pi ME ee 98-102 "EET SPIES) LT 2 Sz ae eee ree 102-107 cexperunenisin Michican. .....22..--.0-..--------- pn) RRs Bt 92-98 Seapee tte rime trough eg So oe SL ee ee eee 87-91 SPCEEEIEEA Tay Th TST CPS a a ag cre eee pe ee eae eee oe 107-109 Davinson, W. M., Jonzs, P. R., and, paper, “‘ Life History of the Codling Moth in the enan Gera Valley GF Cali Ornia?) fe $74 252. a2 eee a ee Distillate-oil emulsion, tobacco extract, and arsenate of lead eons pear thrips TeES BOTTI TENT le Se ee re ee ae ese 179-180 Parworunacsemeon codlme moth. - S<._ 2s _ < 2h). 8