Historic, archived document Do not assume content reflects current scientific knowledge, policies, or practices. 2 & : e s | > j ” “ . i , ; a UNITED STATES DEPARTMENT OF AGRICULTURE LIBRARY BOOK NUMBER P69P Suppl, poet A Ve o2= 66 em f° (> “i a: Be a ‘@) 6193 Be 192721928 ero 8—7671 i: _ ISSUED BY | THE OFFICE OF MYCOLOGY AND DISEASE SURVEY Aor ARS ae neces Supplement 52 \ Diseases of Fruit and Nut Crops NG In the United States in 1926 July 30, 1927 ‘BUREAU OF PLANT INDUSTRY a UNITED STATES DEPARTMENT OF AGRICULTUR * Shak we Pat ae © é TA rick a H. R. FL es Bt ots Be eHU ste ge DISEASES OF FRUIT JET AND NUT CROPS IN THs UNITED STATUS IN 1926 Prepared by W. A. Archer, Assistant Pathologist, Ofrice of Mycology and Disease Survey.. SECTION ON CITRUS AND SUB-TROPICAL FRUITS Prepared by Fulton, Pathologist, Office of Fruit Disease Investigations, Bureau or Plant Incustry. Plant Disease Reporter Supplement 52 July BO pw CONTENTS PEMEYFOGUCTION sees ensscssceeesesis 4 IOYSveT i at tee ARV Geo ne MAE s laibamuse a Peteediscases of 1926 ....0..-45 3 QUIGe’ @ eels 'ae sae 2 «esl cee ees ene Diseases of pome fruits «..i+. 4 Diseases Of Stone Arwies ie eke. Pie ie! (sliw, wip ele Win sal ob cn! Wane We 4 ISAC h Mie ale sve a oe clea Gk) ela aelonerenee BESO ran la baka iol eiiack wicca 5%) & 4 Buslohiiol Olt, Sey socio GNA lb clo c EA OAC WA ele) win (e 3) bbe) = 0 ll es Sa 9 Wake Wwe SS On sooo cobb 5. Dera RUST: esis ce dese wes dS S@E mare). ume Bir mor ciao 0.5 Pema MEOH AA ae Seva 4s +6 16 Bacter tall SoOs) sell etieen SEMIS UH OIE! ors, e ls x his sie es a 18 Bul Wer Wit ace te Gicieaea on ae rere sun SG ate wise we asia) a 24 Mie Wl OWS: 20 'p shis\a ceils ei eneentonetrene CROWS ZAM s cn eb woe sao 28 Little peaeh i ce «scree Blister Canker .ss++.56. 40 R@SiSibib Guy a eaciley ool es coat aaa eee Powdery mildew ....s.s.s6. ul SOMAY! || LI GRU alain ellen) elena allele WOOLY DLO GM ssa. seca ees ae PROS dey LIA ATEN os 08 a) tale nile lh ete RD) SOONG veya =o. 9» sew oo wl BS VO oa Sp NAL a LAI ool foun Sela ela Bey ier) Paw hea sks one oe ais 44 Miscellaneous disorders Jonathan Spot «+++... ee 54 PAVASE EMC Giese ow eim sie gis King David spot ........ 45 non—parasitic ....-.-- Hroatenntswate ON Wey relate ete)" \al #01 ve" o's 4 PANO seks eneteget a) a) s aia oi arielel ehaMedelt ea OME oe ULIEY ‘\ile\irinte’n bie (4 pie 4 Qe itesre We iterates ay alts) leh ar cr h'(gy) oy etesienty ve WEE LEV IIE Y) a ies ae ole os 4 AIM C Oi Me Comsh «ie 6's a! hs 0 as oie alin ai Miscellaneous Diseases of small fruits ...... PAPASLTIC - er eswnenee 49 GOES ss lp ate «2/6 mg sein mimi 6 x) 5 (elm . non-parasitic ....... h2 SUYAWDEPLY «+ cevaasesvenere ° ackberry See ee Nae we oe Papaya BWHEYTY ga Sees cen ) aes Guava © ; ¥ Date «++ Petje. ‘Fig seteeeeee aie eege cme. Gil Pomegranate a a i es Oe ‘Diseases of nuts Pecan Sa.euas , Walnut tenes Scbiet\s See ee ces iti nn nh STE SSS Cer OMe eet eee mts oe mm TO Le . Pilperk- ene. see ee ete ee reese ree 102 Coconut ..... Saewedeiele eis: ereleleneisr sles) LOZ seaigadG er. Z gH ae Tit ROD Uo © TON .In the preparation of Wie Sey the compilers have madé use of all the uniborae fens received by the Plent Disease Survey during ‘1926 on the subject of Hgacudos of fruits and nuts. This infomnation came ‘principally from three | A rdass nemoly : Been elmeuer: oars of the Plant Disease Survey. who supplied 2 176 individuel plant. reports, from articles in the literature of the year, and from reports fumished by the members of the Office of Fruit Disease Investi- gations. AcknowLedsnent is wede of. the assistance of collaborators and the following nbs re of t the Priit Disease Officc: We S.. Ballard, Charles Brooks, Reeve ee 19040. modge) ai. ©. Dunegan, D. F. Fisher, J. W. Roberts, D. H. Rose, N. he Stevens, and M. B. Waite. PRD COA Siew Sons. Oe 119.216 ee Wate ns SCAB CAUSED BY VENTURIA INARQUALIS (CKE.) ADERH. Apple scab is widespread over the United States and may be considered as the most important of the major diséases- of the apple. Reports of collaborators indicate that since 1918 it has caused an annual loss averaging approximately 5 per cent. The states reporting the heaviest losses during this period of time are: Kentucky, 18 per cent; Maine, 13 per cent; New York, Pennsylvania, and Iowa, each 10 per cent; Tennessee, 9 per cent; Michigan, 8 per cent; Ohio, Wisconsin, South Dakota, Tee North Carolina, and Oregon, each 6 per cent. Seab was of minor importance in 1926, only one state, Tennessee, out of 25, reporting more than usual, while 17, Connecticut, Virginia, Indiana, Nebrask:, Arkansas, Kansas, New Jersey, Mississippi, Delaware, West Virginia, Illinois, Iowa, Missouri, Pems ylvania,, New York, and Uregon, reported less. The loss for the United States was approxiinately 4-5 per cent,- which marks the second success-— ive year of slight infection. The percentage losses reported for 1926 are given in table l. +> Apple - Scab Evidently the hot dry weather during the spring interfered with the nor- mal development, ejection and germination of ascospores and thus reduced the usual infection. Alabama, Delaware, Illinois, Indiana, Arkansas, Massachusetts, Minnesota, Missouri, Nebraska, New York, New Jersey, North Carolina, Ohio, Oregon, Virginie, and Wisconsin, all reported adverse weather for early scab development, and in may states the same unfavorable conditions persisted during the summer. In Minnesota, Wisconsin, Arkansas, and Michigan favorable conditions occurring in the latter part of the season brought on a late infection, especially on the leaves. The data on spore discharge and on earliest appearance are given in tables 2 and 4. ( The following selected extracts from reports of collaborators will repre- sent the general conditions for the year: Illinois: To explain the remarkable absence of scab throughout ‘the southern’ half of the state we must go back to the season of 1925. During that year very little scab developed and as a Consequence the amount of overwintering scab on dead leaves was much below normal. The fall development of scab on the leaves was prevented by hot, dry ‘ ‘weather. Observations on overwintering are meade cach spring at the University, but extreme difficulty was expericnced in finding the perfect stage in the spring of 1926. The growing scason of 1926 opened nearly two weeks late in most sections of the state and for this reason the young leaves were not exposed until the early part of May when very dry weather prevailed throughout the state. Rainy periods in the letter-part.of May.and the middle of June were responsible for rather serious scab conditions in some sections in the northern half of the state. (Anderson) Alabama; . Scab much less ‘injurious than usual this year due to unfavorable weathur for ascospore dispersal. (Niles) Arkensas: Apparently the scason was exceptionally favorablo but scab did not develop as commonly as predicted. Since scab was almost absent last year, the lack of infective mterial might be a factor. (V- H. Young) te Massachusetts: Unusually dry weather prevailed in Massachusetts during April and May,: and as a result ascospore development wes re- tarded and spore ejection delayed. Infection was very light in most orchards. (Osmun, Doran, Guba) Missouri: Usually abundant but scarce this year,. even on leaves. (Archer) New York: Has caused less damage then for several years past. Severe in a few orchards: ef-susceptible varieties like McIntosh but this variety has a light.crop this year. (Mills) North Carolinas As a rule more prevalmt in mountains than in Picdmont section. (Fant) ; ry Apple - Scab Ohio: Scab serious only | in one section of the state. ney CH G Moume yi.) Gey: ; ; / Orezon:: Abundant sunshine and dry atmospheric conditians prevailing in March ana April were rather unfavorable ta spore formation and infection. (Barss) South Dakota:.. Although the season was very hot and dry yet scab is reported to be most severe disease of apple. (Evans) Tennessee: Apparently increasing in seriousness. (McClintock) “Wisconsin: Much less than usual. Most trees show very little foliage infection.. The season has been too dry for scab to develop rapidly. Ci ouesan Pane Indiana ge This is’ the sadand year that apple scab has been mild. There was practically no scab’ in well sprayed orchards, except perhaps in the northeast comer of the state. The season Was very late and rather dry weather prevailed during the com- oe short Lehane wh en ES oo occurs. (Gardner) No new ee Wee been contributed: by Ma barn tore this a coneerning the susceptibility of varieties. . The New Jersey Department of Plant Pathology submitted pivures showing the season's results in experimental control of scab on Winesap and Stayman with various spray and dust combinations and applications. It is clear from these data that spray mixtures give uniformly better results than the dust applications. The sprays and dusts used .were concentrated lime sulfur; colloidal sulfur; 6-4-50, 8-4~50, and 8-8-50 dry mix; 90-10 and 70-10-20. aust: and Kolotex. The regular schédule followed junsia tod of concentrated lime sulfur at Pink and 84-50 dry mix at Calyx,..7 day, 17 day. and 4 weeks. In the. comparison of various Spray materials and combinations it seemed that concentrated lime sulfur all Seasons gave slightiy better control (97-5 per cent scab free fruit) than the regular schedule. In the use of regular schedule combined with dusts it was found that 70-10-20 dust starting at Calyx gave 81. 7 per cent scab free fruit but that Kolotex starting at Calyx gave 87. 6 per cent scab free fruit. The data in table 4 showing correlation between date of spray application and ascospore ejection in 1926 has been contri ted a Schneiderhan as a supple- ment to table 2 which gppeared in his publication (15). He finds that during the last five years 75 per cent of the ascospore ejections have occurred between the Pink and 5 week applications. The results of control studies in Ohio (1 and 4) show that: (a) timeliness of spraying, gaged by spore discharge, is important; (b) controlling initial in- fection is necessary; and (c) the expense of spraying can vary with rainfalls, the latter governing ‘initial infections A graph is given showing the relation of the amount of rainfall to spore discharge. Keitt and Wilson (11) point out the possible value of reducing ascosporic inoculum by the use 6f post-harvest sprays prior to leaf fall. Mention is made of preliminary limited trials with various materials, such as copper, sulfur, mercury, arsenic Ge CHORE SHS, and Se a te cong eae Apple - Scab Roberts and Pierce (14) recommend spraying with lime sulfur solution (a) directly after the opening of the blossom clusters , (vo) immediately after the eat of the petals, and (c) additional spray ings peor 2-4 weeks and fron 8-10 weeks efter petal fall, depending on the weather. Dusts were not found to be as efficient as dilute lime sulfur. | Table 1. Percentage losses from apple scab, as estimated by collaborators, 1926. Percentage: ::Percentage: loss :Otates reporting : lo sotates reporting 16 +: Towa sce sa ; Illinois, Ohio, Penn- 6 : North Carolina, New 8 : sylvania | Heaseny cs 05 : Delaware, Indiana, 9) ; Michigan, Wisconsin, :: : California : South Dakota, Mon- :: - Trace : West Virginia, Minne- ) : tana ‘ Acs : sota, Missouri, North 3 : New York ae : /Dakota, Kansas, 25 : Maryle nd 23 : Nebraska, Idaho, Wash- 2 A Wilreeatiaules sy) Mle ora) 992) 8 :. ington, Mississippi, : Oregon Sif : Arkansas ee oo ° Table 2. Data relating to ascospore maturity and ejection as reported by collaborators, 1926. Q . Condition of fun igus : : First mature : First spore State and locality: Date ores noted: ejection noted Delaware. : March 18 : x . Connecticut : March 20 Bhi x : Virginia, - - : Winchester April 8 : 2 x Maryland : April 28 : : x Michigan : April: % : x : Massachusetts, : : : Amherst : May 4 : oT x New York, 5 : 3 Chautauqua Co. : May 5 = x Wayne Co. > . May % iis x - Dutchess Co. ; May 9 : x : Ithaca : May 10 : x : Canada, g g 3 Ontario : May 10 - x 3 Massachusetts : 5 : West Acton : May 11 = x New York, : é - Ulster Co. : May 17 2 x 2 Apple - Scab : : Condition of fungus As ale 2: First mature : First spore State and locality: Date: ascospores noted: ejection noted Canada, s : Ontario eo Ee AS) : 5 Ohio: 7 « So sil June 1 : Se New York, © Be Nima : Monroe Co. z June 1 : x Ontario Co. : Semen eZee cs : x Table 4. Dates and-places of first observation of apple scab, as reported by collaborators, 192. Date ‘Place: $ Count : _ State April : --- A iets : Tennessee May 8 : --- 5) WKS aso : New York May 8 : Snow Hill : Worcester : Maryland May 14 : Raleigh : Wake : North Carolina May : Bridgeton teh --- -; Connecticut May l : Snohomish : Snohomish : Washington May 20 : Urbana : Champaign po LS IEalyoye aes} May 20 : --- : Bucks : Permsyilvania May 25 : Blacksburg : Montgomery > Virginia May 26 < --- : Simpson : Mississippi Sune yin: --- : Dutchess : New York June 1 : Milford : New Haven : Connecticut June 2 Te GOs ; Augusta ey Ware rave June 9 : Dover : Kent : Delaware June 9 : Greene and : --- : Orange : New York June 9 : --- : Knox : Indiana June 14 : --- : Onondage : New York June 17. re italesahloyabillne ei Cie : Minnesota June 1 : Onterio : <== : Canada June 1 : Amherst : Hempshire : Massachusetts June 24 : Sturgeon Bay : Door : Wisconsin June Miatiie --- : --- : South Dakota (Ss) = Apple ~ Scab Table 4. The correlation between the dates of spray application and ascospore ejections for 1925 at Winchester, Virginia. 2 Duy cu iee bh . i DEtes son yal ie, peat Ne spray ¢ Spray olication : Ascospore ejection Delayed Dormant . Mareh Sl 5 April 8 CUNO MB oct OMNI oa : Aor tel! PRU TERTS alle: shade melted Od we tet ae ch eas opel 26 5s GAR a Le Calyx 5 May 10 2 ven, 16 3 May 1 : : Guu tiva@edue : : June 14 f 4 : June 15 h-weelc : June 18 cus June 24 ____ 10-weeks : July 5 : Total : crak ) Recent litereture dies. rty- - Ohio Agr. $2426 (Bul. 392): 11-99. Mar. 1926. 2. Bagenal, N.:By, 7. Goodwim, ie control of apple scab.’ Jour. Min. Agr. Great Brit 7 38-45.. Apr. 1926. WN ee i) }) ou, F. He, and [. Pe lewis.. Spraying to control apple sc eC t tern Ohio. -Proc. Ohio, State 4. Bremer, H. Ausbaumdglichkeiten in der Prlanzenschutzstatistik. (Seispisl: Bie Besierungen des Apfelfusikladiums zum Wetter.) Nachrichtentl. Deutsch. Pflanzenschutzdienst OG: WEP TZa35) ISS - 5- Dutton, W. C. »Concentration of mterials and rates of application in the control.of apple scab. Michigan Agr. 1 : : : 1G = a7 Hxp. Sta. Techn. Bul. 7o: Lee Se walneal 1926. 6. Howitt, J. u., and ¥. G. vans. Prcliminery report of some Observations on ascospore discharge and dispersal of conidia of Venturia inasaualis (Gke.) Wint. Phytopath. 16: hH9-503. Aug. 1926. f+ Jehle, R. A., and H. A. Hunter. New factors in scab development. Rept. Maryland State Hort. Soc. 20: 157-164. 1926. Apple - Scab; Blotcn 8. eitt, G. WV. Some relations of environment to the epidemiology and control of apple scab. Proc. Nat. Acad. Sci. 12: Goal ewe.) 19260 4 8 q we 9. es _ Otudiss of apple scab and cherry leaf spot infection under controlled conditions. (Abstract). Phytopath. 1/72 Ab. Jan. 1927. WS : is and L. K. Jones. Studies of the epidemiology and eae control of apple scab. Wisconsin Agr. Exp. Sta. Res. Bul. 73: 1-104. Dec. 1926. sibils and 8. 8. Wilson. A possivle reorientation of oe aims and méthods for. apple scab control. (Abstract). Phy topa th. Ae aoe Jan. Tei: 12. Ostervalder, Ae sce ee ee aus den Janeen 1915-1925. Zcitschr. Pflanzenkrenkh. 26: 79-97- 1926. iss, Peuhervridge, Po Re, and We A. aD oe OSS eropeaghlene and cxjeriments on apple’scab in Hast angiia.e Jour. Min. agr.s Great Britain 32: 1119-1127-. Mar. 1926. 14. Roberts, J- We, and Le Pierce. jsnpple scab.e U. 5S. Dept. Agr. Farm. Bul. 1y76: i121. 1926. 15. Som Aderban Bel der Ponte disease studies’ in northern Virginie. Virginia Agr. Exp. Sta.. Bul. 245: 3-355. 1926. lige ShearssEs Ve Tidld trials of spray materials on apples in i925. Proc. New York State Hort. Soc 71; 145-150. LAOS Te iy. Thurston, H. W. Pennsylvania's cxpericnce with the dusting i HEE of apples. Proc. Ohio State Hort. Soc. 59: 150-140. 2925. | BLOTCH CaUSED BY PHYLLOSTICTA SOLIT:.RIA ELL. & EV. Of the pele epple @iseases in the’ United States bloteh nanks about third in importance according to reports of collaborators during the pest nine years. As mentioned in previous reports the disease is rather sharply confined to the area south of the 42nd parallel and east of the 100th meridian. A comparison of Big. 1 of this pinloIevoeeel orm With Fig. 2 in Plant Disease Heporter Supplement 14 Will show that an extension in the area of severe infestation and loss has occurred in ail diy rections, perticularly eastward and southward, since 1920. In @ig> 1 there are indicated’ the localities in Minnesota, Wisconsin, Michigan, and New York where iniection has been reported outside the usual area. These are oi interest in conjecturing on the possibility of blotch spreading into northern 10 Apple - Blotch states. This year in Rock County, Wis consin, Vaughan reports a new location, stating that blotch occurred with a lete scab infection. This report coupled with thet of Last year from Waushara County, where 50 trees with a 75 per cent infection were found, would lead to the assumption that the disease is gradually gaining a foothold in the state. The situation in New York on the other hand may be somewhat different since Taones reports ne 52 "Blotch on apple seedlings planted at Ithaca in May 192/ has shown only slight spread on the originally infected trees. Only one small cahker has been found on one of five budded trees inter— planted with these scedlings. Clean seedlings planted in a row continuous with the infected seedlings show no blotch at the ed of three seasons. Each of three lots of infected seedlings, the shipment of which has been traced, came to New York from Towa." Likewise Bennett reporting for Michigan states that blotch is extremely rare and that it was observed on trees smt in from southem nurseries. He states: "Specimens of blotch were received this spring from River-. side. Upon investigation it was found that the trees had been set in the spring of 1924 and that all trees were badly infested When received. There was a gnall anount of infection on the growth of Pe the grawth of ree) shows no signs oe rote and this season's growth is also free. Indiana collaborators report the discovery, in September, of cankers of nursery origin on young trees at Marquette, Michigan. This is the farthest north that blotch has been reported yet. In’ the meantime reports of collaborators in Tilinois, Inciana, Ohio, Pennsylvania, and New Jersey indicate that each suc— ceeding year the area of infestation steadily creeps northward. Estimated percentage losses are given in table 5. Collaborators’ re— ports on the prevalence of blotch in comparison with the normal year show that the season of 1926 was perhaps an average year, since out of 18 states di: re- port the usual prevalence while 7 report less. : The following are’ the’ only reports of value contributed this year on the subject of the relation of the weather to blotch. Iiilinois: The weather in southern Illinois where blotch is a real problem could not have been more unfavorable. May and June were extremely dry and even unsprayed-Duchess was free from infection. Some blotch developed at the northern edge of the blotch region, i.e-, from Neoga north to Champaign, but even here the control was easily accomplished by the few sprays ap— plied. (Anderson) Tennessee: Warm and moist weather favorable to disease. (McClintock) ; Virginia; Sufficient rain to cause spores emission. Hot weather and late season rains favored the dissemine ti or (Schne iderhan) iat Apple - Blotch Spore emergence and infection data were: received from Virginia and Tllinois as follows:. a Virginia: A close correlation between spore emissions and the relative values of blotch sprays was found to exist in our experimental work on blotch control in: 1925 and 1926. There were nine spore emissions from blotch cankers in 1926. The first. occurred May.19 and the last on July 10. The average time between emissions was six days. In 1925 there were only seven. emissions occurring eight days apart, from May 24 to July.15. In 1925, 57 per cent: of the early spore emissions occurred just after the 5-weeks spray. In contrast to this, approximately 55 percent ofthe total spore emission ‘occurred earlier in 1926, namely, just after the application of the 3-weeks spray. Compared to the total seasonal control value, the 5-weeks spray in 1925 was valued at 59 per cent, while the 3-weeks spray in 1926 was worth 55 per gent. These values were determined from our blotch control expe riment. (Schne iderhan) Illinois: Conditions in 1925 account in part for the behavior of blotch in 1926. Very little blotch was present in 1925 and thus twig infection was raree Many orchards were ex- amined where bloteh.had been serious in previous years and the wood of 1926 was found to be nearly free of cankers. Howey ee cankers and ‘spores were abundant on the 1924 wood, so that there was no lack of Sources. of infection in the Spring - of (1926 (see data under weather condi tions): (Anderson) In aenenet the Sa uieeor cuore report thet sp ray ing - gave g00d | control in the following states: Tennessee, Ohio, Arkansas, New Jersey, Delaware, Pennsylvania, Virginia, and Missouri. W. H. Martin reports good control in New Jersey by the use of the regular schedule, 2-A-50 Bordeaux mixture 4-10 weeks ~ after petal-fall. In Ohio (1) it was oe that under the conditions of the experiment Bordeaix gave considerably better contzxol of blotch than lims sulfur. eels Stated that from the results of two years' tests it would seem inadvisable to use lime sulfur for the cleming up of blotch in a badly infested orchard. It was further found that the effectiveness of lime sulfur depm@mds tipon the time of blotch infection, which is entirely regulated by weather conditions. When the infection was gaeye as in 1924, lime sulfur was very efficient, especially where the 2-, 4-, and 6-weeks sprays were applied. On the other hand, when the infec-— tion was late, lime sulfur was less effective, due, undoubtedly, to the long period between the 6-weeks and sccond codling-moth spray. Cenker eradice tion gave effective oontrol results in Ind iena according to Gardner. He states that: "The effectiveness of canker eradication in relation to prevention of the disease in young plantings was demonstrated by the second year's results in: the two blocks of Duchess from Which the blotch sprays were omitted. These blocks were in orchards in which the canker eradication campaign was begun in 1922. A good crop was Eaoapee’ this year anc a careful exami nation of the fruit showed practically no infection in the 12 ‘ Apple -— Blotch unsprayed blocks, a result which indicates not only. that the canker eradication hd been successful but that there is very little long distance spread of blotch by such agencies as wind, insects, or birds." : Gardner (4) young apple again reports the cffectiveness of blotch canker eradiertion in two orchards of Oldenturg in which was demonstrated freedom from fruit infection in blocks of trees left unprotectcd by the blotch spreys during 1925 and 19 26. One of the orchards was set out in 1917, -the other in 1918. The Sans tion campaign was begun in 1922 end consisted of shaving off or pruning out the old cankers and spraying to prevent the formation of new cankers. Me tedialataran : oo LAA ules sote, Wis io on Ho +4 Lis) A r aoceSeeusesseser= <= a ia Heth zi BRED 2EED? =e sonsin uaa Buaaeasiee ji Lobe ee i a ij iG : “| fexfebeteroto elu p ap pes pees oo eo els Mi ehigan. ae Senne coe samuwar a OP? EE RAR RE RD Pe See 3 fh ¥ / : ae Ren : §? “and. New York hve in. Minne- Side the usual range. The numer— is indicate the yeer of the | saa report. w {iili] = severe. \, = [EERE =. slight to moderately Severe. payed 3 _— Fig. 1. Distribution of apple blotch in the United States - : rc ‘A revised to 1920. 14 Apple « Blotch; Cedar Rust Table 5- Percentage losses from apple blotch, as estimted by collaborators, 1926. Percentage: : ::Percentage: - loss :States reporting aa loss :otates reporting 15 : Missouri . 3: -.: .[llinois 5 : Tennessee = — 25 25 ; New Jersey 4 : Kansas ‘i 22) irae: 3 Delaware, Virginia, 505 : North Carolina, Alabama :: : West Virginie, ots 7 ONO, Tharana >) sis ae : Georgia, Wisconsin, fle : Maryland, Mississippi, Eyeoe ; -: Iowa, South Dakota :. Texas, Arkensas, enie Recent literature 1. Anon. Forty-fourth Annual Report of the Ohio Agriclturel Experiment Station for 1924-25. In Ohio Agr. Exp. Sta. Bul. 392: 11-99. 1926. | 2. Ballou, F. H., and I. P. Lewis. Spraying to control apple -+-scab and apple blotch in southeastern Ohio. Proc. Ohio State Hort. Soc. 59: 165-151. 1926. 5. Gardner, M. W. Apple blotch canker eradication. (Abstract). Phytopath. 17: 4o. Jan. 1927. , Le Greene, and C. &. Baker. Spraying tests for the control of apple blotch. Trans. Indiana Hort. Soc. 65 (1925): 134-147. 1926. 5+ Kohl, Edwin J. Details in the life-history of the apple blotch _ fungus. (Abstract). Phytopath. 17: 45. Jan. 1927. 6. Roberts, J. W., md L. Pierce. Apple blotch. U. S. Dept. Agr. _ Farm. Bul. 1479: 1-11. Apr. 1926. : CEDAR RUST CAUSED BY GYMNOSPORANGIUM JUNIPSRI-VIRGINIANAE SCHW. According to reports of colleborators during the past nine years cedar rust ranks about fifth among the m jor diseases of apple and is confined to the eastern half of the United States. The &verage annual loss since 1918 is estimated at Slightly more than 1 per cent, with Virginia, North Carolina, West Virginia, Iowa, Nebraska, South Carolina, and Missouri, in order of importance, reporting the heaviest losses. This year the ma jority of the states reported the prevalence of the disease to be the same or less when compared with last year and with the average year. Nebraska, Kensas, Connecticut, snd Arkensas reported more in com- eer en SL Tee Ne 4 Apple - Cedar Rust parison with last year md with the average year. ‘The percentage losses in 1926 are given in table 6. Goss reported that in Nebreska cedar rust caused more damage this year than any other apple disease and that there was severe injury on fruit, whereas usually only leaf infection occurss Thco--early season Was very Gry, re tarding somewhat the developmat lot, fruat aay leavese In Ksensas, White reported a heavy infection which caused defoliation of susceptible varieties. Fant in North Carolina reports that damage to foliage is aoe greater then to fruit. The information received on susceptibility is included in the fo downs notes and in table 6. Fant states that in North Carolina the susceptibility of Magnum. foliage to. infection has been noted for a number of years. ‘White reports that in Kensas infection on Wealthy hes bem so severe thet normal twig’ growth will be hindered. In Virginia, according to Schnciderhan, the susceptibility of York to infection varices widely cven in the same orchérd. The younger and rapidly growing trees are much freer from the-discase-them the-oldor-ones. He explains that it seems to be a case of correlation of vigor resulting from ferti— lization and cultivation with lessened susceptibility. Data on relation to weather conditions in 1926 are very meager. Ohio and South Dakota report-unfevorable weather conditions for rust BEET OUE while Tennessec and, Mississippi report favorable condi ti ons. . Virginia: Dry carly scason prevented teliospore formtion and ejection. There were 10 tcliospore ejections in 1926 from April to July 4, while in 1925 there were 21. _Teck of rainin April and May evidently accounted for this difference. In spite of fewer spore ejections, the infection was heavier in’ som’ places than in 1925. /(Schne ider han) - > The Following notes Were recejved concerning the relation of cedars to Arkensas: Rather prevalent and serious Where cedars have not been cut, but reported in muy areas supposedly clcarcd of cedarse (V. H. Young) Minnesota: Only traces found in vicinity of cedars. (Dept. Ple Path.) Virginia: Occurs in epprcciable smounts only whceré red cedars arc very near to apple trees. (Fromme) | 15 Apple -— Cedar Rust Table 6. Percentage losses~from cedar rust. of PPEES as reported Dy collaborators, 1926. Percentage: ::Percentage: loss: _: states reportin loss _:States reporting By : Virginia =) a ; Tennessee, Ohio 2 t North Carolina, Trace : Delaware, South Caro- 3, Arkansas, Iowa, Kansas:: lina, Alabama, I ' Connecticut, West Vir- :: Mississippi, Michigan, ginia, Illinois, South: Wisconsin, Minnesota, Dakota eis : : Missouri -25 : Maryland : ve : : Table 7.. Dates ‘and places of first observation of cedar rust of apple, as reported. by collaborators, 1926. SEMAINE Ine meee ° Mie ue Place Date : County otate yo} ap Ol aa ag) --- --- Tennessee May 40. : Winchester 7 Prete rLek : Virginia ih June 3 Spartanburg ° ; Spartanburg. : South Carolina June f : Manhattan Glee: Kansas June, Le Sueur : Le Sueur : Minnesota June 9 s Mitchell Lawrence - : Indiana June 10 : Mt. Carmel ; Néw Haven : Connecticut June 11 : Cumberland --- : New Jersey June 2A : Millsboro : Sussex : Delawere July 15 : Madison : Dane ; Wistonsin July 19 --- ; Ulster : New York Table 8. Comparative susceptibility of apple varieties as reported by Fa Sos 3 1926. Very susceptible: Susceptible : Resistant : Very resistant : Immune Ensee 4 Jonathan 2 Rome 2, 8 Wealthy 1,45,4 York & : Grabs 5 : ‘Delicious 7, : : Golden De- ay licious 6 ° e : Newtown: £ ; Henry Clay 4: : McIntosh 4: Gano 4 Grimes 4 : Delicious -4 : Stayman 8, Winesap 6 : York Imperial 4: : Arkansas 4 : Grimes : Northwestern A Crg@etalnirayss /Al Stayman 4 > Winesap 4 Apple - Cedar Rust; Black Rot SS SqnSOese AIS | SSC bees Resis tant ae resistant Immune : es neon Aa : : Palouse A $ OR : Ycllow Trans-— : am ) : : 2 perch 2 : Rome 7 : : ; : : Starr 7 ; : : : : Wealthy 6 ; : 3 : Winter : : : i : Banana 0,7 The numerals uscd in the table above refer to the collaborator and- state-from-which-the data was. received,-as. follows; 1. G. P. Clinton in Connecticut. 2. M. W. Gardner in (iad 5+ J+ @. Gilman in Towa. 4. R. Pe White in Kansas. 5. Minnesota Department of Plant oe W. Ae Archer in Missouri. Path ology. 8.° F. J. Schneiderhan'‘in 7: WW. He Martin in New Jerseye» ©. = + Virginia. Recent literature 1. Hast, W. H. Cedar cutting. Proc. Virginia State Hort. Soc. 30 (1925): 84-87. 1926. 2e Schneiderhan, F. Je Cedar rust stucies in 1925. Ene Virginia State Hort. Soc. 430 (2925): 134-140. 1926. BLACK ROT O07 APPLE CAUSED BY PHYSALOSPORA MALORUM (PE.) SHRAR In general this discase is more preval@t and causes most loss in the eastern half of the United States, although it is found occasionally in western apple groving statcs. From reports of colleborators during the past nine years it is estimated that black rot canker, leaf spot, and fruit rot have caused an everage yvarly ioss of slightly less tan. 1 per cent. During this period the states reporting the heaviest Losses have been North Carolina, South Carolina, Georgia, and Ohio,-cach with an-approxim: te-average of A per cent; Tennessee, Okichoma, end Iowa, cach cpproximately 4 per cent; and Penmsy lvenia, vest Virginia, Kentucky, Mississippi, Indiana, ° and Missouri, each approximately 2 per cent. In 1926 the majority of the states report that the prevalence of the discase is the same or more compared with both last year ond the average year. Delaware, Mississippi, and Ohio report less in comparison ta last year and the average year. The following table 9 indicates thé extent of losses reported this year. Fruit rot infection follow ing codling moth injury Was mentioned in the following reports: 1’ Apple - Black Rot Virginia: A year of heavy codling moth injury like 1926 is always followed by considerable black rot infection. (Schnei derhan) ; Arkansas: Much fruit injury in oeualns Greet cra with eodiing moth injury. (Dept. Pl. Path.) Ellinois: Black rot was more prevalent than usual because of severe codling moth infestation. (Anderson): _ Delaware: There was lesS infection on early fruit- but more on the fall crop because of insect injury. (Adams): In Minnesota ,. according to the Section of Plant Pathology, black rot fol- lowed fire blight and caused dana ge most Ly as Gane cankers. Direct loss of fruit was slight. ; Leaf infection was reported as important or serious in Connecticut, New York, Pemmsylvania, Delaware, Maryland, and Missouri. In the last named state Cankers and fruit rot were found but rarely. In Michigan and North Carolina, on the other hand, the canker form was most important, the latter state reporting severe Canker injury both in young and bearing orchards. Jehle reports from Maryland that leaf spot was abundant on parts of trees Where dead wood was not removed and the seme fact was observed in Missouri by Archer. In Ohio, according to H. C. Young, sulfur dust does not control black rot defoliation entirely, mt a regular schedule of lime sulfur reduces its prevalence. Additional susceptible varieties, York Imperial, Red Astrachan, Delicious, and Wealthy are reported by Martin in New Jersey. The ennual report from Minne- sota states eu Ge ein (Od aides is affected more often than that of other kinds. The literature and records in the Plent Disease Survey indicate that Sphacropsis malorum causes three types of injury, viz., fruit rot, canker, and leaf spot. Of the - three, it appears that quite often the leaf spot causes most Severe injury through defoliation, and also is often difficult to control by Spraying. Sphaeropsis malorum Pk., Phyllosticts limitate Pk., Coniothyrium pirinum (Sacc.) ) Sheldon, Coryneum foliicolum Fell., Phoma mali Schulz. & Sacc. etc., are found rather commonly associated with the leaf spot. Table 9. Percentage losses from black rot of apple as estimated by collaborators, 1926. Percentage: ; ::Percentege: loss rotates reporting loss :Otates reporting 5) : Maryland 23 : Michigan MS : Iowe et -75 +: Alabama 205 ries @) 38 Ko eal rs ol : Tennessee 2 : Arkansas, North sie Trace : Missouri, Minnes ote, Carolina Hie : -Tilinois, West Vir- Ie} : Connecticut, Virginia:: : ginin, Delaware, i : Indiana, Kansas, eae : ‘ Texas 18 Apple - Black Rot; Bitter Rot Recent literature i. Cooley, Js S.,,md Hi Aline Fenner. The variability in the black rot fungus of the apple. Phytopath. 16: 41-A6. 1926. 2. Lebedeva, L. Ae le Sphaeropsis malorum Peck Be arbres fruitiers. Zeshch. Rast. Vred. (Defense des plantes) 2: 588-992. 1926. 3. Stevens, N. E. Occurrence of the currant cane blight fungus on numerous hosts in the Southern States. Mycologia 18: 278- 202. 194. 4. Walton, R. C. Black rot of apple. In Pennsylvéenia Agr. Exp. Sta. Bul. 204 (Ann. Rept. 39; 1925-26); 15. 1926. BITTER ROT CAUSED BY GIOMERELLA CINGULATA (STON.) SPAULD. & SCHRENK Bitter rot occurs principally in the southern and eastern portions of the United States, in the area limited by the Ohio Valley on the north and by the Mississippi Valley on the west. This region may be defined more accurately as bordered on the west by the ninety-fifth meridian and on the north by the fortieth parallel, except along the eastern coastal region where the disease occurs in southeastern Pemsylvania, New Jersey, New York, and southern New Mngland. The states suffering most loss, according to the estimates of the Plant Disease Survey, are Temessee, South Carolina, Georgia, Alabama, Kentucky, North Carolina, Mississippi, Arkansas, and Missouri. The disease is locally destructive during some years in Virginia, in the sothern parts of Ohio, Indi- ana, and Illinois. The situation in the various states may be mentioned briefly. First, considering those an the border of the bitter rot area, the fol- lowing seems to be evident. . Along the western border the disease is limited by insufficient moisture. In Texas the disease is of little importance. In Okla- homa it appears in scattered localities to a negligible extent. In Kansas and Nebraska it is unknown except for a narrow region along the Missouri boundary. In Iowa the disease is rather rare, although observed occasionally in southern counties. In Wisconsin and Michigan it is unknowm as an orchard disease. In New York it is sonfined to the counties bordering the Hudson River and sath of Albany. In New England*it issometimes important orr susceptible varieties in the southern part when weather conditions favor the disease. In New Jersey, Pennsylvania, Delaware, and Maryland it assumes destructive proportions locally during epidemic years. In West Virginia during earlier years it ocmrred in epidemic form from time to time, but in recent years it has become much less serious, owing apparently to the elimination of certain trees of susceptible varieties which seemed to act as carriers. Coming now to the states in which bitter rot is of more importance, we find that in Virginia it is rated as one of the mjor apple diseases. In general it is secondary to cedar rust ad scab, but in the Piedmont Section, éspecially in Albemarle, Nelso, and Amherst Counties it usually outranks other diseases of apples and is the one most feared by the growers. This section grows the 19 Apple = Bitter Rot highly erized, birt. very susteptt bit Yellow Newtown, or Albemarle Pippin. In some years growers of this variety have had their crops practically wiped out by bitter rot. In the Carolinas, Georgia, Alabama, and Tennessee bitter rot is regarded as.. the most serious apple disease and requires more attention than all other apple diseases combined. In. Kenticky and in the southern fruit-producing areas of Illinois, Indiana, and Ohio, bitter rot is not of great importance when consid- ered over a period of several years. In seasons with warm and wet weather, how- ever, epiphytotics are likely to ocmr and heavy losses sometimes result. When the average estimates of losses for the past eignt years for the country as a whole are considered, we find that bitter rot ranks about sixth in importance of the diseases of apple, the average annual loss being estimated at slightly less then 1 per cent. The losses in 1926 seamed to be somewhat less than normal within the usual zone of severity, but apparmtly there was some in- Crease in the*amount of damage along the northern border, particularly in Ohio, Indiana, Meryland, end Kansas. The estimted percentages reduction in yield in the various states for 1926 are given in table 10. The highest percentage loss were reported fram Temesseco and North Carolina, but a greater loss in bushels occurred in Ohio bectuse of its larger crop. The average annual percentage stat losses according to estimates for the past cight years are presented on the ac— companying map (Fig. 2). The increase in severity of the discasc elong the northern border of the bitter rot arca seems to be correlated with the prevalence of weather favorable for the development of the fungus as show by the following reports: (@) Marylend: Hot and moist conditions in August and September were favorable. (Temple & Jchic) Tennessce: . Heavy rains in August made bitter rot spread rapidly. (McG@lintock) Ohio: Temperature aid moisture both favorable. (H. C. Young } In the Proétorville and Gallipolis sections bitter rot was markedly destructive this season. This outbreak was rather lo- calized in that territory, but quite a number of orchards had the entire erop destroyed, particularly Rome Beauty and Grimes. (ieee Dye, Niagara Sprayer Co.) Indiana: Heavy and frequent rains in fall caused rapid spread. (Gardner) ees Missouri: A cool and somewhat dry summer probably reduced infection. (Archer) _ Virginia: The temperature was favorable but there was not enough rain in midseason to cause exudation from mummies. (Schneiderhan) = The dates and locations of earliest infections in 1926 as reported by collaborators are given in the accompanying table He Several resistant and susceptible varieties were reported this year, but all have been listed before with the possible exception of the Missouri Pippin reported as susceptibdle by Archer from Missouri. For the first time in New Jersey |W. H. Martin reports Grimes, Winter Benana, and Maiden Blush as susceptible var- leties. 20 Apple .-: oo aes Rot Three states, Virginia, Indiana, and BERS: report good results fran cradication of bitter rot mummies. The results of this and other control measures as Well as notes on overwintering and infection studies are given be low Virginia: ‘The ability of the eee rot fing us- to live over- for two years in mummics was demons trated at Winchester on June 40. A wire cage containing bitter rot mummies of the year 1924 was the center of infection on Harly Harvest. Later the same fact was noted in Northwestern Greening. Infection was obtained on Harly Harvest apples again on July 10 by inoculation from bitter rot mummies two years old. These mummies had been exposed in this tree for two seasons including the past winter. There was a possibility of twig infection in the tree because three years ago a large portion of the apples were artificially inowlated by exposure to mummies. This possibility was climinated after,the mummies were soaked 40 minutes and then piled on top of apples. The checks were -not dis-— eased under a bell jar. Infected twigs exposed with these mummies in the same tree and used in the same manner have not produced in- fection in the damp chamber. For the fifth year bitter rot is reported on. ie old Smokehouse trees. These trees were demumified this spring to such an extent that no mummies could be found for bitter rot spore exudation data. As in previous years the whole crop will be a loss. .The evidence again proves that twig infection is the method of overwintering of the funguse (Schnciderhan) - . Indiana: Bitter rot became very serious in southern Indiana, especially where the fungicide was omitted in the July sprays. The disease was first noted the last of July and the frequent rains caused it to spread very rapidly. The sources of early infection of bitter rot under Indi ane conditions are not well knovm. Cankers are very rarely found. Old mummied fruits hanging on the tree are a dangerous saurce of infection and should be removed. Growers are instructed that sanitary measures should be adopted this fall to minimize the danger for next year. Ail rotted fruits should be raked from umer the infected trees. In removing mummies care should be taken to remove the stem. of the fruit since the fungus may. grow : up into the stem and thus serve as a source of infection. Many growers wage an active campaign against bitter rot diring the late summer not only by spraying, but by watching the trees and. removing the infected fruits as soon as they are noticed. Failure to use Bordeeux with late codling moth sprays on Grimes ) results in mech rot in that variety. (Gardner) Illinois: Aside from a few local outbreaks this discase was I not serious and no complaints were received. The weather was un- | favorable for bitter rot in those sections where this disease is | normally serious until Jate in the season. The general ebsence of the disease in 192) may account in part for the comition in 1926. In an orchard Waere the disease was serious in 1925 and where the aw Average loss:6 to 7 per cern a | ~Average loss: 1 to 4 per cent. Average loss;0.5 to 0.9 per cents Average loss: trace to 0.4 per cent. Fig. 2. Average annual percentage loss from apple bitter rot, 1918 to 1926. 22 Apple - Bitter. Rot mummied. fruit was allowed .to remain on the ground there was another outbreak in‘1926. In another orchard where the diseased fruit was carefully picked from the trees in 1925, not oniy was the disease «. Checked but no bitter rot appeared in 1926 in spite of favorable Weather the latter part of August. (H. W. Anderson) Table 10. Percentage losses from Des noe rot of apple, as estimated » by collabor at ors, 1926. Percentage: ::Percentage: loss rotates reporting sae loss rotates reporting 5 : Tennessee ts ae -: Delaware, Virginia 3-5 : North Carolina wot: Trace : New Jersey, Illinois, 2 : Maryland, Ohio,’ South 3: : :Missori, South Carolina — = : : Dakota, Arkansas, i : Mississippi, Indima, :: : West Virginia, Texas : Alabama, Kansas 23 : * Table ll. + Dates and places of first observation of bitter rot of apple, as reported by collaborators, 1926. Date Place Count; State June 40 : Winchester “~~: Frederick’ -: Virginia July 12 : --- : Chatham - ; North Carolina July 15 : ~ -- °:..* : Madison and : Tennessee : : Jefferson > ae July 26-31 : --- + : Warrick : Indiana July 29 : Jackson | : Cape Girardeau : Missouri July 29 : Bridgeville : Sussex : Delaware August 2 4 --- : Middlesex : New Jersey August 16 ; Proctorville : Lawrence : Ohio September 10: A. & M. College: Oktibbehe : Mississippi September 21: St. Charles Heh Ante te : South Carolina October 1 : Hemden or New.Haven, . : Connecticut Recent literature 1. Anon. Forty-four th Annual Report of the Ohio Agriculturel Experiment Station fyr 1924-25. Ohio Agr. Exp. Sta. Bul. 392: 1- 100. AG2Gw 2. Shears EV Ws Fiéld tials ‘of spray materials on apples in 1925. Proc. New, York Sta. Hort. Soc. 71: 145-150. 1926. 25 FIRE BLIGHT CAUSED BY BACILLUS AMYLOVORUS (BURR.) TREV. Fire blight is widespread in the United States and judging from reports of collaborators during the last nine years it would seem to be about the second most important disease of the apple for the country as a whole. The average toss in the United States during the past nine years is estimated at about 2 per cent. The great majority of the comparatively few reports received this year indicate that the prevalence and severity of the disease is about the same as last year and as uSuale New York, Indiana, Wiscmsin, Missouri, Pemsyivania, Iilinois, and Towa report more Bes nee the average year; while Ohio, Michigan, North Dakota, Nebraska, Kansas, Washington, Arkansas, Colorado, and Oregon report less. Losses estimated are given in table 12. Some of the collaborators’ reports regarding the prevalence and importance of the disease in 1926 follow: New Hampshire: Disease rarely fourd. Of no economic importance. (Butler) Connecticut: Only two reports. Qne of some injury to blossoms (this usial) and one of moderate injury to leaves and twigs. (MeClint ock) New York: Severe in central od southem part or stete. (Milis) In Onondaga County fire blight cau sed considerable damage particularly in orchards where nitrate of soda has been used for Several years. (D. D. Ward) severe in central erd southern New York and elsewhere, even in Clinton County. (Barrus) Pennsylvenia: Blossom infection epidemic in west, moderate in east. Twig blight apperently increasing in importence. (Thurston) Virginia: In the Norfolk section .appic a farm-yerd crop. This season fire bligat i especially in die-back stage. (McWhorter) Disense always of minor importance. It causes slight los in the form of twig blight. Cankers are rare. Fruit ieeceeton is practically unknown. (Schneiderhan) Ss are grown only as S. unusually severe, : Kentucky: Considerable blossom and twig blight. (Valleau) Tennessee: Spur blight on early varieties. (Baskin) South Carolina: Dama eee pLossom and twig blight and cankers of small bren i - (Llodwig)- -. Alabema: Abuncent blossom blight in northcrn part of state. (Miles) Apple - Fire Blight Indiana: The worst disease of the year was the veritable ‘scourge of fire blight which broke all previous records for severity on apples. It was worse in some parts of the state than in others, the southwest comer being especially hard hit. (Gardner) Michigan: Blossom blight was only slightly serious. Twig blight was very destructive in the northern and eastern part of the state. Cankers were produced in large numbers. (Bennett) Wisconsin: Farm orchard situation in critical condition. (Vaughan) Missouri: Third successive year of severe damage. (Archer) North Dakota: Important in the eastern and northwestern parts of state. (Brentzel) ; Kansas: Moderately important in the northeastern and in the eastern part of state; also in Arkansas Valley. (White) Oregon: Severe blossom blight in the eastern part of state, but no damage in Willamette and Hood River Valleys of my economic significance. (Barss) the relation of pear trees to infection of apples is indicated by the first three of the following reports: Missouri: Serious all over state where pears are pres@mte Where pears are absent the blight is practically negiigible. (Arch er) Imiana: Pear trees seem to be a very dangerous source of early infection for apple orchards. (Gardner) Arkansas: All evidence points toward the efficacy of pear eradication as an important factor in this year's situation. Pears have been largely eradicated from many apple growing sections of northwest Arkensas with a marked reduction in the incidence of fire blight on apples. Many orchards in the vicinity of pear plantings are suffering severely. (V. H. Young) Illinois: The disease started rather late in the season appar- ently not doing much damage during the blossaming period. It re- appeared as a spur vlight, probably having been dormant in the blossoms. The almost total absence of aphids in the state indicates that some other agent must have been responsible for spread this season. Practically no twig blight has been observed. (H. W. Anderson) Nixon (2) has attacked the study of fire blight from a new angle. He has studied (1) the migration of the bacteria through apple tissue; (2) the effect on the host cell; (4) longevity and life cycle of the pathogen; (4) varietal tests for root immunity, together with (5) a new method of pathologic histology ces =a) Apple - Fire Blight whereby immunity studies can be made microscopically. As a result of these stud- jes nearly 1,200-trees of the more promising seiections-have been planted to test out their adaptability in locations favorable to infection. -H. W.- Anderson in a -report to the Plant Disease Survey advances the theory that when aphis are absent little early blight infection is to be expeodted. In Tllinois this year, aphis infestation was extremely rare and blight did not occur until much later than usual. He states further: "Spur blight was quite severe and was remarkable that it did not develop until after petal fall. It is possible that the blight bacteria were introduced by pollinating insects but that weather conditions deiayed the development of the disease. Again it must be admitted that blight can bécomé serious during a dry spring. This is the second season that this fact has impressed uss. Favorable weather for inséct pollination may be a factor. --~- “Ore of the outstanding facts in-regard-to fire blight is~ - the seriousness of cenkers in Willow Twigs in the western part of the state. This condition has been noticed in past yearse It should be a well known fact that the soverity of blight in- fection on any variety is not an index of the number of hold- Qver cankers which my be found. Thus,~Jonathan is one of our” worst varieties for twig blight, and Transparent the worst for “body blight, yet on ncither of these can“hold=over cankers be found. Certain other varieties, partiqlarly Willow Twig, which do ncot show scrious twig or blossom blight, on the other hand do have abundant hold-over cankers." Collaborators' reports on the susceptidility of varieties are given in the following notes and in table 1%. : Wisconsin: Hold-over cankers most serious in Transcendent Crab. (Vaughan) Indiana: The Jonathan variety was most severely injured. The infections were not only more numerous than ever before but procecded down the limos mich farther than usual. Actual fruit infection was very common in Transparent early in July. The fruits were often one-quarter grown before becoming infected. Grimes is subject to severc blossom blight but the twigs secom fairly resistant. In Duchess this year only the late bloom was blighted, a condition which held truc for certain other varieties. Turley blighted worse than Winesap, and Golden Delicious did not seem to be as resistant as Red Delicious. Cankers have not been common except in Jonathan, Esopus, and Red Detroit. Badly blightcd trees of these varieties may carry the disease over winter. (Gardner) Minnesota: Folwell apple very susceptible in nursery roWSe Some of nurserymen plan to discontinue growing this variety. (Sect. Pl. Path.) 26 - Apple — F Table led. ; ::Percentage: Percentage: loss :States reportin : Missouri ire Blight loss 25 Percentage losses from fire blight. of apple, as estimated by collaborators, me tates reportin: South Carolina, Arizona a! e : Mississippi 14) : Alabama 5 : Indiana, Michigan, Be : Chio, Kansas, West : North Dakota Virginia, Tennessee, A : Maryland 7 Membenee oa 4-5 . : North.Carolina, “5 : Conrecticut, Delaware ) : Arkansas -4 +¢.Galifomia 3 : Minnesota, Iowa, ~~ Trace : Virginia, Idaho, South Dakota, Texas ; Washington, New Hampshire, 2 : Ti3inois, Wisconsin, =::_ : New York, Oregon Table 13. Comparative susceptibility of eas to fire blight as reported by collaborators, - (1926. Very susceptible : susceptible = =: _Resistant : Very resistant Chenango (8) : Baldwin (4) Esopus (3) 5 Folwell (5) King (4) Maiden Blush (6) Red Detroit (4) Benoni (4) : Black Twig (9) : Delicious (9, 10): : Dr. Matthews (3) : Duchess (4) Strawberry (8) : Early Hervest (9): Transcendent Crab : Golden Delicious : (4) BAS) Wagener (1) : Grimes (2) Yellow Transparent : Jonathan (10) (6) : King (1) : King David (3) ; King Genet Loomer cece : Lilly (2) : Maiden Blush (3) : Missouri Pippin : Moon (9) : Northern Spy (3) : Northwestern : Arkansa Ss) Bile (3) : Baldwin (8) : Carson (3) Clayton (3) : Delaware Red : Fallawater (Tulpehocke (3) McIntosh (3) Northern Spy : Ort ley (3) : Red June (3) : Rhode Tsland ck +: Black Twig (3) : Gano (3) ::Kinnard (3) : Lawver (3) : McMchon (3) : Minkler (4) (3) n) Salome -(3) (4): . Greening (3) Tetofsky ee heler [ce o : Williams Sy : Winesap (6) : York (6) — meee eee ia ii Ss Apple - Fire Blight Zi) LO OS NON ON NN SN ONO CO ON] OUIBW MH eee ee eee eee eee oN a ee +651 O ——— Repor ted Re por ted Repor ted Repor ted Repor ted Repor ted Re por ted Re por ted Reported Rep or ted Reported susceptible Susceptible; Resistant : Very resistant Ozark (9) au Red Winesap (9) : Rhode Island = : Greening -(8) : ' : Rome Beauty (9) = 58 Simmons Red (9): Stayman (4,9) : : Transparent (2) : 2. Turley (4) Cry. rie : Twenty Ounce (8) : Wealthy (3) : Western Beauty F (9) : : ee : . kts Willow (4) : : York (4) sc sate from from from fron from from from from from from from ihe Turdey. is 175- Recent literature iy 2. Cardinell, He A. Grow. Assoc. Ontario 57: 85-90. 1926. Connecticut by G. P. Clinton. Delaware by J. F. Adams. Indiana by M. W. Gardner. Michigan by C. W. Bemett. Minnesota by Dept. of Plant Path. Missouri by W. A. Archer. New Jersey by W. H. Martin. New York by M. F. Barrus. Scuth Carolina by L. M. Fenner. Virginia by F. J- Schneiderhan. Wisconsin by R. E. Vaughan. a new variety described in Hoosier Dene en “Ann. Rept. 1926. Fire blight control. Fruit Nixon, E. Le Migration and transformation of Bacillus amylovorus in apple tissue. (Abstract). Phytopath. 16: Sie 1926. SCL ee, : Fire blight. Pennsylvania Agr. Exp. Sta. Bul. 203: 1-22.- June 1926. : 28 CROWN GALL CAUSED BY BAC TSRTUM TUMEFACTENS EFS. & TOWNS. abe Fee Ae es ee ee Pe we oe SO men tcl ci ewe a Tn. 19.26,. as in previous years, t the reports of. occurrence of crown anid and of losses due to it came mainly from fi furseries. In Missouri, however, a large orchard was seen in which one-fourth of the trees had been affected with callus galls and hairy root at the time of planting several years ago, and at the present time fully one-fourth of the trees are either stunted or dead. Several of the stunted or dead trees were aig and, in practically ail cases large galls were found on the roots. Presumably the gall formation had seriously inter- fered with water transference. Similar galls- were found on young trees which died in scattered localities in the state. | 2 Arkansas: Often over 50 per cent of nursery stock rejected; supposedly because of crown gall but probably much of it is not crown gall. (Dept. Pl. Path.) Minnesota: Three to four per cent of nursery stock infected with bacterial crown gall (estimate from Nursery Inspection Service.) (Sect. Pl. Path.) _ Michigan: One nur ser y reported 90 Bes 22a. 8 the apple nursery stock affected. (Bennett}—~2 7" one or Patna sot North Carolina: Hai 1 r oot. noted: by nur sery . inspectors in several localities this year. (Fant) Arizona: Gre Os Aonsie. ee serious diseases. (Street) In Tennessee the disease is moderately important. In New Jersey, South Dakota, Washington, and Idaho it. is ; ony slightly important. In Delaware, according to Adams, Y "Infection is generally prevalent in some plantings and the increased weakming of trees has caused their removal." Muncie (8) suggests that the abundant development of fibrous roots from an overgroythat the union of piece-root grafted trees is not a reliable index of crovmm gall infection. Numerous attempts at isolation, using Patel's modi— - fication, yielded negative results, and likewise inoculations of macerated tissue of fibrous root did not prodice galls upon young tomato plants. Over- growths closely resemlbing those found on discarded nursery trees have been induced upon aseptically made grafts and scion cuttings planted in sterilized Soil. Isolations from these malformetions did not yield Pseudomones tumefaciens. It seems evident that these overgrowths were causcd by excess callus formation at the tip of the scion lip of the graft and scion cuttings. The "wooly knot" form of hairy root was obtained repeatedly by artificial infection under con- trolled conditions. It was discovered that the pathogen could retain its virulence at least 154 days after infestation in non-stcrilized greenhouse soil. It was determined that gall formation interfered considerably with the rate of water flow. Patel (12) monas tumefaciens eg Apple - Crown Gall isolated both pathogenie and non-pathogenic strains of Pseudo- from overgrowths and from nursery soils. Cultural characters of the two strains were quite similar. Pathogenic strains have retained their virulence after two years in culture. Riker (13) in his experimental studies finds that gall Poet on is stimu- lated in tomato by low temperature (18 - 22° C.) and on tomato and raspberry by excess moisture. Effective agglutinans were secured by intraperitoneal injections of the pathogen into ES ae - Recent literature eee non? Burr-knots in ‘apple trees. (Science News, Science ' Service)?: Science nes. 65: JEXIT- Jan, 1927. 2. Fejgin, B., T. Epstein, and C. Funk. Sur trois. souches de Peerenees isolées des tumeurs malignes. Comptes rendus - Soe. de Biol. 94 (3): 199-201. 1926. 3. Hatton, R. G., H. Wormald, am A. W. Witt. ‘On’ "burr-knots" of fruit trees. Jour. Pomol. & Hort. Sei. 5: 195-204. July 1926. A. Levine, M. The éffects of radium emanation on the crown gall tissue. Amer. Jour. of Roentgenoog y and Radium co oe 1A: BESS. 1925. 5. Magrou, J. Ile Bacterium tumefaciens dans les tissues du cancer des plantes. Compt. Rend. ade ‘Sci. Paris 183; 804-606. 7+. Medhus, | Nov. 1926. ‘Sur l'anatomie du cancer’ des plantes ou crown gall. Compt. Rend.- Acad. Sci. Paris 133: 986-988. Nov. 1926. I. E&. Crown gall amd graft. knots of apple.» Amer. ’ Fruit Grow. Mag. 47: 4, Al. eel 8. Muncie, J. He A study of crown galt Gaused by. Pgeudomonas | tumefaciens on rosaceous hosts. Iowa State College Jour. Sci. 1: 67-110. 1926. = : ; The effect of crow “gall on young apple and peach trees and longevity of Bacterium tumefaciens in the soil. (Abstract). Phytopath. 16: 79 6 1926. 10. and C. Berkhout. Water conduction in apple trees affected with crow gall. Proc. Iowa Acad. Sci. 31 (1924): 143-146. 1926. erect ee oe 11. Oppenheimer, H. R. Verhutung und Heilting’ krebsartiger Pflanzengeschwiilste (Vurzelkropf der Obstbaume). Angew. Bot. 8: 8-29. 1926. é Apple - Crown Gall; Blister Canker 12. Patel, M. Ke Strains of Pseudomonas tumefaciens. (Abstract). Phytopath. 17: 46. Jan. 1927. 13. Riker, A. J. Studies on the influence of some environmmtal factors on the development of crown gall. Jour. Agr. Res. 32; 83-96. 1926. 14. Cytological studies of crown gall tissue. Amer. JoOure Biotes 14: 25-47 6 eval, 1927 - 15. and G, W. Keitt. Studies of crown gall and wound overgrowth on apple nurs ery stock. Phytopath. 16: 765-808. lov. 1926. BLISTER CANKER CAUSED BY NUMMULARIA DISCRETA (SCHW.) TUL. Blister canker apparently has not spread, or if so but little, since the distribution map was published as Fig. 8 in Supplement 1f of the Plant Disease Survey of 1920. The map shows that the disease is practically confined to a tier of states extending cast of the one-hundredth meridian to the Atlantic coast; and south of the forty-second parallel to a line which includes the northern corner of Oklahoma, the northern half of Arkansas, and all of Tennessee, but not including any of South Carolina. In addition to this main area of general infestation there have been scattered reports from various sur- rounding states. In general the disease has been of most importance on old neglected trees, especially Ben Davis, ard reports of collaborators indicate that drought con- ditions are favorable to development of the fungus. In 1926 the prevalence was reported to be the same as last year and as in the average year, except in Illinois where Amerson and Tehon report mores The only lossés reported this ycar were Missouri, 5 per cent; Kansas, 2 per cent; Illinois, 1.2 per cent; Ohio, O-1 per cent; Maryland and Virginia, each a trace. The following are the only reports of interest received this year: Tennessee: No infection seen in 1926. (McClintock) New York; Slowly on the increase as young orchards mature. (Thurston) Arkansas; Probably decreasing in state as Ben Davis is sup- planted. (Dept. Pl. Path.) Miss uri: Most important disease of old trees. Old ne trees are inveriably attacked and killed. Many die every ye (Archer) glected are Table 14 gives data on the relative susceptibility of varieties from various states. . “i Syl Apple - Blister Canker; Powdery Mildew Table 14. Relative suscep ti bi lity of apple varieties to blister canker as reported by collaborators, 1926. Susceptibility Varieties and Authorities Very susceptible : Ben Davis (1,2,3,4,5,6); Gano (A,5); Genet :__- (3); Maiden Blush (3); White: Pippi yas Susceptible : Clayton (3); Delicious (2); Jonathan (3); : Mammoth Blgck Twig (3); Rome (3);.Stark (3)... . (1) Arkansas Department of (2)-H. W. Anderson and L. R. Tehon Plant Pathology. “sin Titineiss (4) M. W. Gardner in Indiana. a W. A. Archer in Missouri. (5) H. C. Young in Ohio. (6) F. J. Schneiderhan in Virginia. POWDERY MILDEW CAUSED BY PODOSPHAERA LBUCOTRICHA (ELL. & EV.) SAIM. In general it seems that powdery mildew has been most troublesome in Cali- fornia, Oregon, Washington, Idaho, and Utah. Perhaps the most severe losses have occurred in the Pajaro Valley of Califomia and in the Walla Walla, Yakima, and Wenatchee districts of Washington. In Colorado it is reported as very important. Eastward the most damage occurs perhaps in some of the Middle Atlantic States, particularly on nursery stock. cee Sen et In 1926 the disease was mostly repor ted to be of about the usual prevalence. California and Arizona each reported 1 per cent loss; North Carolina,. 0.6 per cent; Maryland, Virginia, West Virginia, Minnesota, Iowa, and Colorado, each a trace. In Wisconsin, Minnesota, and Iowa the disease was important only on nursery stock. According t». the Arizona State Commission of Agriculture, powdery mildew was much less prevalent in 1926, due to careful pruning and spraying. Fromme states that in Virginia infection was noticeable on Ben Davis, York, and particularly. on Jonathan. In West Virginia also it appeared mostly on Jonathan, according to Sherwood. Fisher reports that Jonathan, Grimes, and Black Ben were very suscep— tible in Washington. The Tasmanian Goverrment (1) gives the results of spraying experiments with tron sulfide and atomic sulfur for mildew control, the former injuring the leaves less but the latter giving better resiltsS.. Oppenheimer (3) states that applica- tions of "Cosan" combined with pruning are effective in controlling mildew on nursery stock. Schubert and Richter (4) describe at length a series of laboatory and field experiments in the control of apple mildew and other fungous diseases by means of castor oil potash soap emulsions of hydrocarbons with phenol bases, and mixtures of hydrocarbons with phenols, and a preparation of tar components known as pomastin. They consider that the phenols are likely to prove of great importance in plant protection. SEO i et eee Bb 32 | ae se: a Apple ~ Powdery Mildew; Sooty Blotch; Flyspeck Recent literature 1. Anon. Powdery mildew-e Results of expe rime nts. Fruit World of Australasia 27: 221: 1926. — ; 2. Foéx, E. Notes sur quelques Erysiphacées- Bul. Soc. Myc. de France 41: 417-438. 1926. 3. Oppenheimer, H. R.- Die Therapie der Baumschulkrankheiten. Angew. Bote 8: 137-146 1926. 4. Schubert, K. and K. Richter. Studien zur Bekémpfung des. Apfelmeltaues (Podosphaera leucotricha) und einiger -anderer Obstbaumschiédlinge: pilzkicher. und tierischer Art. Angew. Bot. G2 446-167.) 1926, 220°: ua SOOTY BLOTCH AND FLYSPECK CAUSED BY GIOEODES POMIGENA (SCHW.) COLBY AND LEPTOTHYRIUM POMI (MONT. & FR.) SACC. These two diseases are widespread in eastern United States, but the principal losses have been reported from the Middie Atlantic and Ohio Valley States southward. In 1926 sooty blotch was reported to be more or much more prevalent tha either last year or the average year in Delaware, Maryland, New Jersey, Arkansas, Illinois, and Minnesota. The losses reported were Virginia, 6 per cent; Maryland, © l per cent; Iilinois, 0.7 per cent; Delaware, New York, Kansas, and Missouri, a trace. It was reported.as important on unsprayed fruit in Arkansas, Indiana, and Michigan. According to H. W. Anderson: "An unusual condition resulted in many of the western Illinois orchards because of the extremely wet weather in August and September which brought about an unusual outbreak of sooty blotch. In general the disease was serious only in those orchards where late spraying with a fungicide was neglec- ted. Where a fungicide was included in the second brood codling moth spray there was little trouble." Schneiderhan observes that "sooty blotch was the most important disease of apples in Virginia in 1926. The reason for this unusual importance is found in the fact that all spraying was discontinued in June because of the arsenic residue problem. In addition, the heavy rains in the late growing season re- Sulted in very favorable conditions for infection." ae mh DS Apple - Sooty Blotch; Flyspeck; Fruit Spot Martin states that in New Jersey, "sooty blotch was observed on Rhode “Island Greening, Bismarck, Fallawater, Northern Spy, Wealthy, York, Grimes Golden, “Maiden Blush, Golden Pippin, and Ohio Nonpareil... Northern Spy was especially sus- ceptible in Michigan, while Grimes Golden is reported as very susceptible in Indiana and Missouri." FRUIT SPOT CAUSED BY PHOMA POMI PASS. Records of the Plant Disease Sur vey since 1908 show that this disease is restricted to the region from Maine to North Carolina westward to Iowa and Arkansas. The prevalence and losses vary considerably from year to year in each state. The disease appears during one season and may be entirely absent the “next. Fruit spot usually does not cause severe losses over a whole state, rather it may be confined to a single variety, perhaps in a restricted locality, although there have been reports in some years when the damage equalled that caused by some one of the major apple diseases. In 1926 there were but few reports from collab- orators, however the fragmentary data indicate that the disease was more prevalent than either last year or the average year and that the losses were greatest in a “group of eastern states, i-e., New Jersey with 1.5 per cent loss; Delaware, Maryland, and Ohio each with 0.5 per cent; and Virginia with a trace. Missouri also reported a trace. In Ohio, H. C. Young reports that a great deal of the “Gisease developed on fruit in storagee In New Jersey, W. H. Martin reports: "In some sections of Burlington County this is the. most serious disease the fruit grower has to contend with.: . Obser- vations showed that infection took place puch earlier than formerly supposed." Walton and Orton (2) also discovered that fruit infection could take place Much earlier in the spring and later in the fall than was thought to be the case. These investigators have connected Phoma pomi Passer. (Cylindro spor ium pomi | Brooks) With a perfect stage belonging to the genus Mycosphaerella, probably M. Pomi Passer. Positive infections were obtained on Baldwin, Grimes Golden, and | einen with cultures from single ascospore isolations. | The 1926 data on varictal susceptibility can. be summed up in the following: Varieties reported susceptible - King David in Missouri; Stayman and Golden | |Delicious in New Jersey. Varicties reported very susceptible - Grimes Golden and Jonathan in New Jersey. Delaware reports that the disease was generally prevalent on fall varictics. | ; | ‘Recent literature 1. Walton, R. C. Apple fruit spot.. In,-Pemsylvania Agr. Exp. Sta. Bul. 204 (Ann. Rept. 39; 1925-26): 15. 1926. ai and ©. R. Orton. The perfect stage of Le ia latent pomi. Science n.s. 63: 236. Feb. 26, Loe 34, BITTER PIT, NON-PARASITIC | Bitter pit occurs widely in the United States. In some years it is de- structive in eastern sections, ‘while in the irrigated apple dis tric ts of the West it is one of the more important apple diseases. The reports of collaborators in 1926 indicate that the disease was present in the Middle Atlmtic and Ohio Valley states, New York, Michigan, Minne- sota, and Oregon. The losses reported were, Virginia, 5 per cent; Ohio, 1.5 per cent; Michigan, 1 per cent; Maryland, 0.75 per cent; Delaware, 0.25 per cent; New Jersey, West Virginia, and Illinois, cach a trace. Anderson and Tehon re- | port it as occurring mostly on fruit from young Delicious end Winesap trees in westemm Illinois. Schneiderhan, in Virginia, reports Winesap and Rome subject to bitter pit, and York, King David, and Grimes to be very liable to attack. He states further that: ~ "Practically 15 per cent of all cull apples in northern Virginia had bitter pit. It is the commonest non-parasitic and the most important disease in Virginiae® Bennett reports Northern Spy to be susceptible in Michigan. According to Hd..C. Young -insOhio: "A considerable amount of this discase’ appeared in storage, apparently due to the excessively wet weather prevalent before and during harvest." Recent literature 1. Duriez. Une maladie nouvelle di pommier. Pomol. Franc. 1926 (1): 17-18. Jan. 1926. 2. Smith, A. J. M. Bitter pit in apples, a review of af problem. Bch Rep. Food Invest. Board. Great Britain 28: 1- -2A. 1926. JONATHAN SPOT, CAUSE UNDETERMINED The reports of collaborators show that Jonathan spot was perhaps slightly more prevalent this year in comprrison to last year and the average year. As to losses, however, there were but few reports as follows: Illinois, 1 per cent; Delaware, 0.25 per cent; Maryland, Virginia, Ohio, Michigan, Minnesota, Oregon, end Missouri, a trace. Anderson and Tehon report for Illinois that there was a 10 per cent loss in grade of Jonathans which constituted about one-tomth of the entire apple crop. According to Bennett, 20 per cent of some lots of stored Jonathans in Michigan showed spotting; in Iowa too, stored fruit in local mrkets showed a high percentage of spotting. Several states specified Jonathan as the most susceptible variety but in addition Delaware reported the disease on Stark Delicious end Rome, Minnesota on Wealthy, and-Michigan on Northern Spy. 35 Apple - Tom then Spot; “King David Spot Harrison (1) in 6 ee tenting on the polatt on of tempe rature. to the keep- ing quality of the Jonathan apple concluded that Jonathan spot developed more profusely at higher temperatures. Pentzer (3), ina histological study of the skin of affected apples, determined sbhat the normally red pigment in subepidermal cells was bluish~brow in spotted regions. A-colorimetric determination showed this condition to be associated with a defici ency. of gcid (P 4-7 compared with 2.8 for normal tissue). The use of paper wrapppers impregnated ‘with various harmless acids is suggested as a control. Récent literature 1. Harrison, J. Ee. The Jonathan apple in cool storage. Jour. Dept. Aer Victoria a (1): 31-38. 1926. land 26 elie tiatacr. re Die fleckenbilduné beim Jonathen apfel. Zeitschr. Pflanzenkr. 36: 264-269 . 1926. 4- Pentzer, W. T. Color pigment in reletion to the development of Jonathan spot. Proc. Amer. Soc. Hort. Sci. 22 (1925): 66-69. 1926. eee 4. Plagge, H. H. Prevention of storage disorders in apples. Amer. Fruit Grow. Mag. Ab. (10); 3, 18. Qct. 1926. KING DAVID SPOT, NON-PARASTTIC P -A brief cate of this apprently new disease on the King David variety is 8iven by Robbins (1). He states that the spot ting ‘ce curred on fruit approeching maturity during le te summer, and that the dis ease is characterized by the occur- rence of circular, dark brown to. ‘black, slightly sunken spots, 2-6 mm. in diameter, centered usually abut a lenticel, and more abumant on the side of the fruit ex- posed to. the sun. The disease is considered to be physiological in nature. Brooks and Fisher, Office of Fruit Dis ease Investi gati ons, submit the following report: "A spotting of King David apples has been an annual occur-—_ rence in the Pacific Northwest for a number of years and occas- ionally hes been reported: from Virginic end other Eastern’ States. The spots often are almost indistinguishable from bitter pit, differing in: that they are always superficial with no deep- Seated areas out. of contact with the skin. ‘This "pit" type occurs on the cheek of the apple, generally in the’ ‘médian’ por- tion or tovard the calyx end. In other cases. King David spot resembles. typical Jonathan spot in that only skin cells are affected. It differs, however, in that it first appears long before the apples are mature on the trees and does not increase in storage. It differs also in being more prevalmt on the grecn Side and frequmtly is confined to groups of spots adjacent to the 36 tae Apple = King David Spot; Root Rots calyx lobes or the base of the stem. Both the "pit" type and the ‘less severe injury are -at.first dark green in color, later be- coming dark brown'or blacks . ~~ .: 4 +a wees a "King David spot has: shewn no response “to ‘irrigation and ee = . fertilizer experiments conducted at: Wenatchee, Washington, but there has been a correlation: between its occurrence and more or less severe aphid infestation." © ex. ~~ ae a ogc nt = Gardner in Indiana reported in 1926 that the surface type of injury of bitter pit (presumably King David spot) occurred rather cena ey on ee David, with a trace on Rome. ve = Recent literature 1. Robbins, W. J. Botany. In Some .new.developments - in agricultural science. Report.of the: Director... Missguri Agrs Exp. Sta. Bul. 236: 44-45. ow ROOT ROTS Armillaria root rot (Armillaria mellea (Vahl) Quel. } Tennessee reports Armillaria root rot to be generally distributed, caus-— ing an estimted loss of 2 per cent. In Mississippi the disease was local with a loss of only a trace. In Oregon it was scattered and appeared mostly on land which had been cleared of oak. The disease was reported merely as present in Arkansas, New York, and Ohio. Miles remarks that, "one orchard in northern Alabama showed 20 per cent of trees dead in the last five years, and 12 per cent now show external and evident signs of disease. The loss for the state is probably 2 per cent." Zeller (5) states that it is a widespread and destruc- tive orchard disease in the Northwest, especially in that portion of the coast — states west of the Cascade Mountains. Infection of the roots may take place (1) through wounds, (2) at points of contact of diseased and healthy roots, and (3) at point of emergence of lateral roots. Other root rots Ozonium omnivorum Shear is reported as causing death of apple trees in northern Arizona, especially in irrigated farms. Loss estimated at 4 per cent. H. R. Brisley and Streets}. Tarbenhaus reports a 10 per cent loss for Texas. He says that because of this disease apples cannot be grown in the black lands. Hypholoma sublateritium Fr., according to Thomas (3), was found associ- ated with crown injury of ‘apples in New York. (see also winter injury, page 38) Xylaria spp-, black root rot. Only-five collaborators. sent data relat- ing to occurrence of this root rot. Virginia reported a loss “ab te 5 per cent, and Illinois and Marylend, a trace each.s In Tennessee it was considered to be of moderate importance, while in Michigan it was said to be extremely rare- Schneiderhan reported from Virginia as follows;. "Xylaria causes our commonest Bi) on - ‘dingy Rous; bora} Piiey root rot. A survey of 25 of the best orchards in ricaeeveR County indicates an - average mortality rate in trees of 15.2 per cent. Black root rot is considered » to be responsi ble for at least half of this trouble. Sporulating Xylaria was found in July." A maximm infection of 10 per cent was found in an orchard of Yellow Transparents in the Ozark region of pi aN ae accord ing to Anderson and Tehon. : Hawkins (2) remarks that from veda 2 to Illinois reports have been made of orchard infection by Xylaria polymorpha (Pers.) Grev., X. hypoxylon (Linn. ) Grev., ami X. digitata (Linn.) Grev. It is known that the . parasitic infection by these species £s very destructive to apple orchards, and cases are cited east of the Mississippi River where they also affect pear trees. Both Hawkins (2) and Thomas (3, see also winter injury) state that the fungus attacks. through injured bark. Recent literature 1. Carne, W. M. Root rot of fruit trees due to Armillaria mellea. Jour. Dept. Agr. West Australia II, 3: 429-432. 1926. 2. Hawkins, Stacy. Some Xylarias of Indiana. Proc. Indiana Acad. Sei. 35 (1925); 225-229. 1926. 3. Thomas, H. E. Root and crown injury of’apple trees. Cornell Agr. Exp. Sta. Bul. 448; 1-9. 1926. 4. Valleau, W. D. Root troubles Gee AP %o flly death of apple oes Trans. Kentucky State Hort. Soc. 1925: 141-155. 192. : clio iatctedndliy he Zeller, 5S. M. Observations on infections of apple and prune roots by Amillaria mellea Vehl. Phytopath. 16: 479-484. July 1926. SPRAY INJURY In Delaware, according. to Adams, "Pyrox" (containing copper) caused severe leaf-yellowing on weakened trees. He says also that arsenical dust (90-10) ceused typical spotting on the foliage of weakened Williams and Barly Ripe. From New Jersey, Martin reports that a summr strongth of concentrated lime-sulfur caused severe leaf burning and that even Bordeaux mixture caused damage in some orchards. The Division of Plant Pathology in Washington reports that more injury than usual _ occurred from oil sprays, Bordeaux, and lime-sulfur-s Oil injury took several foms including reduced vitality of trees and reduced size, spotting and russeting, and premture dropping of the fruit. The necessity of limiting arsenic residues On the fruit stimlated extensive commercial use of summr oil sprays. In south- eastern Ohio, Ballou and Lewis (1) find that low temperature and excessive cloudi- ness and moisture just previgus to and during the blooming poriod favored rmsset injury to apples from sprays. They say that their work of the past four years Shows thet much of the msset injury caused by caustic sprays occurs in the use ea 38 Apple - Spray Injury; Winter Injury of Bordeaux fa the pink spray of fruit buds. On the other hand, dry lime-sulfur straight through the spraying period gave 94 per cent of clear, unrusseted fruit on the Ensee variety, which is partiqmlariy susceptible to spray injury. Hydrate lime used in the same manner gave 96 per cent unrusseted fruit. Grubb and Hat (3) maintain that post-blossoming use of lime-sulfur entails a considerable risk of reducing the crop. Osterwalder (4) summarizes the results of ten years' ex- periments with sprays. Bordeaux and various commercial spray mterials generally induced foliage injury while, on the whole, lime-sulfur preparations (1-40 pro- portions especially) were more efficacious than the copper mixtures. Recent literature Le «Ballou,,Fs,He, and I. P.- Lewis. Spraying to control apple scab and apple blotch in southeastern Ohio. Proc. Ohio State Hort. Soc. 59: 165-101. 1926. 2. Farley, A. J. Spray injury. Rept. Maryland State Hort. Soc. 26: 165-167- 1926. | 3. Grubb, N. H., and R. G. Hatton. Post-blos soming use of lime-sulfur spray and fruit dropping. Gard. Chron. -79: 424-325. 1926. 4. Mogendorff, N. Some chemical factors involved in arsenical injury of fruit trees. New Jersey Agr. Exp. Sta. Bul. 419: 1-47. 1925. 5. Osterwalder, Ae Schorfbekdmpfungsversuche aus den Jahren 1915-1925. Zeitschr. fir Pflanzenkrankh. 36: 79-97. 1926. 6. Shutt, F. T. The examination of Canadian sp ray ed apples for arsenic. Analyst 51: 91-492. 1926. 7+ Sutton, G. Le Tests to determine the presence of arsenic in apples after treatmmt with arsenical sprays. Jour. Dept. Agr. ‘lest Australia II, 3: 221-225. 1926. Oy) Weleox, Beis Apples and arsenic. Engiand's complaint brings some - new suggestions for @achard spraying. -Country Gentleman 91: 21, 5-665, « 19266 WINTER INJURY. Arkansas; The extremely dry weather of last summer combined With variable winter weather has resulted in a great deal of injury, especially to young apple trees on the exposed southwest side. An unusual number of both old and young trees have died this season. (V. H. Young) oy Apple - Winter Injury; Parasitic Diseases Minnesota; Some apple trees killed and many twigs killed back from tips. Wet weather in late fall (1925) following ex- tremely dry weather caused late growth and failure of preper ripening of wood. (Sect. Pl. Path.) : Michigan: Young orchards of Grimes and Yellow Delicious were considerably damaged by an October freeze in 1925. (Bennett) Missouri; There is a serious crown and root injury on Jonathan and Grimes. The Missouri Pippin shows evidence of being resistant. In some 15-year old orchards there is a loss of 20 per cent of the trees and it is estimated that 75 per cent of the orchards over 10-years old in the central portion of the state show from 1 to 10 per cent dead or dying trees. (Archer) i In New mane Thomas (3) found Sauces. cael especially Xylaria and lypholoma, to be associated with root and crown trouble; from artificial infec- tion and from observation he decided that the action Sy low temperature on im- mature crown amd root tissues is primarily responsible. Scrious root injury caused by low winter temperature occurred on apple in the northeastern part of Kansas, according to White. Missouri and South Carolina both reported the oc- ‘urrence of basal cankers on apple due to freezing injury. Bradford and Cardinell (1) base an analysis of the relation of winter con- ditions to fruit culture in Michigan during a period of 80 years on an exhaustive study of the literature including available weather records. It was found that intense cold was not necessarily a cause of winter injury, bu when combined with either unusually heavy autumn rainfall or long drought, was a potential source of demage. Lack of maturity in the wood is deemed the grea al factor in inducing Winter injury, and in this connection pr olonged mitivation and heavy manuring nave proved unwise practices. The location or site of an orchard is potentially important from the standpoint of winter injury. Recent literature 1. Bradford, F. C., amd H. A. Cardinell. Eighty winters in FE ieee orchards. Michigan Ste. Spec. Bul. 149: 3-103. My 1926. 2. Sandster, EB. P. Winter killing of apple trees in Colorado. Pruit Belt 24 (3): 18. Mar. 1926. 5+ Thomas, H- HE. Root and crown injury of apple trees. Cornell Mer. Oxps Sta. Bul. AAG: 1-9. 1926. MISCELLANEOUS PARASITIC DISEASES Botrytis sp., blossom-cnd rot, reported by Heald and Sprague (A) to be he cause of a spot rot in storage. | _ Gercospora mali Ell. & Ev., leaf spot, ane Corticium salmonicolor Berk. & Br. Burt eon 228) lists this as para- Pas, On apple, pear, and fig shoots in Florida and rae iit Appic - Parasitic Diseases Corticium galactinum (Fre) Burt, reported by Burt (2, ps 202) as occur- ring on living roots of apple in Arkansas, Illinois, and Missouri. Corticium stevensii Burt (Hypochnus ochroleucus Noask), according to Miles caused con- Siderable twig blight in two orchards in hort caster Alabama. Glocosporium perennans Zeller & Childs, perennial canker, was reported by the Division of Plant Pathology to be of moderate importance in eastern Washington. It occurs both as a canker and a fruit rot. Winesap is resistant but Spitzenberg is very susceptible. In Oregon, according to Zeller, the dis- ease is less prevalemt than usal. He says that: "As a canker, new infections Were almost nil this year but fruit picked after the first fall rains was materi- ally reduced in storage and transit’ due to a rot produced by this organism. The Canker is linked with winter injury but none of the latter occurred during the previous season." Barss reported thet perennial canker and anthracnose together caused 10 per cent loss in Oregon. Leptosphaeria coniothyrium (Fckl.) Sacc., orange pox canker. Fromme states that specimens of the fungus were received from Bryant, Nenad oa The injury was very slight. ‘ Myxosporium corticolum Speg., superficial bark canker, was observed in all parts of New Jersey by Martin. . Nectria galligena Bres., European canker. Zeller (10) fully describes this disease as it occurs in Oregon. -He reports for 192 that the disease was practically absent due to the fact that trees had not been subjected to winter injury during the preceding season. However, the disease was recorded in the White Salmon section of Washington. Mills indicates that it is of slight im- portance in New Yorke Maryland and South Dakota both report losses as a trace. Species of Nectria, Gibbecrella, Fusarium, Cylindrocarpan, and Remularia are reported on bark of Pyrus spp. by Zeller (eK Neofabraea malicorticis (Cord.) Jack., anthracnose, reported to be moderately important in western Washington and in the White Salmon Section; and also in western Oregon. (see perennial canker) Penicillium sp., blue mold rot, occurred commonly. Phoma mali i Schulz. & Sacc., canker. A report of this disease has been published in Plant Dis. Rept. 10: 124. Nov. 1, 1926. Phytophthora cactorum (leb. & Cohn) Schroet., fruit rot. Indima - Heavy rains in late fall and summer made favorable conditions for infection of Grimes. It occurred only on fall@m or low merging fruit. (Gardner) Pleospors spe, fruit rot. Rose and Butler (7) state that the fungus, presumably P. herbarum citrorum, was isolcted several times from PaaS shipped from Washington, Oregon, and California. Pleurotus subaveolatus Pk. was reported in Washington as slightly im- portant as a heart rot of Staymen Winesap. Fisher suggests that this fungus may be identical with P. corticatus of Europe but material wes lacking for confirmation. Rhizoctonia sp.-, damping-off, 5 per cent loss as damping off in young seedlings in Texas. (Taubenhaus Schizophyllum gommune Fr., heart rot. In Missourion old trees in neg- lected orchards; loss a trace, according to Archer. The disease is also re- ported from Washington. Sclerotinia fructicola (Wint.) Rehm., brown rot, is widely distributed on apples in the United States but the losscs ordinarily are quite small. In 1926, losses were reported as follows: Maryland, 0.5 per cent; New Jersey, Virginia, North Carolina, Ohio, Illinois, md Kmsas, cach a trace. Dowson (4) discusses the association of Sclerotinia *PraGhige na with e core rot end premature fall of fruit. Al meiaunt - ah dinate Diseases Stereum purpureum um Perse, associated with silver ee is reported to be quite important. in eastern and central Wash ington. Trametes peckii, reported as the cause of heart rot in an occasional tree in Washington. Nalsa leucostoma (Pers.) Py. , die-back, was reported from New York and Missouri where slight damage ocurred. In Washington it is reported as a canker. Beaumont and Hodson (1) list the various fungi associated with die-back of fruit treeSe Volutella fructi Stev. & Hall, spongy dry rot. Sherwood in West Virginia reports this on Northwestern Greening. Recent literature ds 10. .Beaumont, A., and W. E. H. Hodson. Second Annual Report of the Department of Plant Pathology, Seale-Hayne Agricultural College, Newton Abbot, Devon, for the year mding September 30, 1925: 1-32. 1926. Burt, HiesAe » The Th edieeeies cbc oP: Nbwthyl Anand cers LV (Corticium). Ann. Mo. Bot. Gard. 13: 173-354. 1926. . Dowson, W. J. On acore rot and premature fall of apples associated with Sclerotinia fructigenae Trans. Brit. Mycol. Soc. 11: 155- 161. Aug. 1926. Heald, F. D., and R. Sprague. A spot rot of apples in storage sinc by Botrytis. secs Moa 16: 485-438. July 1926. Murphy, Pe A. Some fungus diseases of fruit trees. Jour. Dept. Lands and Agric. Ireland 25; 269-280. 1926. Pethybridge,' G. H. Fungus and allied diseases of crops 1922-1924. Min. Agric. Mise. Publ. 52: 1-97. 1926. Rose, D. H-, and L. F. Butler. Pleospora rot of lemons and apples. (Abstract). Phytopath. 17: 47. Jan. 1927. Southee, BH. A., md F. T. Brooks. Notes on a pycnidial fungus associated with a dy ing-back of apple branches. Trans. Brit. Mycol. Soc. 11: 213-219. Dec. 1926. Weber, Anna. Sprojtning af frugttraeer og frugtbuske mod snyltesvampe samt disses biologi. (Spraying of fruit trees and bushes against parasitic fungi, together with the biology of the latter.) Tidsskr. for Planteavl. 42: 219-318. 192bo Zeller, S. M. sr eral of pomaceaus fruit trees. Oregon Agr. Exp. Sta. Bul. 222; 1-52. Mar. 1926. Apple - Parasitic Diseases; Non-Parasitic: Dis cases ll. Zeller, S. M. Cankers of ‘bgpie and pear in Oregon oni their . control. Oregon Agr. Exp. Sta. Circ. 73: 1-29. Apr. 1926. ain Species of Nectria, Gibberella, Fusarium, Cylin- drocsrpon and Remularia occurring on the bark of Pyrus spp. ‘in Oregon. Phytopath. 16: 623-627. Sept. 1926. | MISCELLANEOUS NON-PARASIT IC DISEASES Chlorosis, lime induced. Texas ~ Prevalent in limestone regions. (Taubenhaus). Washington - Of slight importance. It occurs locally end is associated with high water table and very calcareous subsoil. It can be over- come by application of iron sulfate in the root area. The disease is very general in the region of Boise and Twin Palls, Idaho, where it causes Severe loss. (Fisher). Wallace and Mann (12) determine that green apple leaves, when compared with chlorotic leaves, contain higher percentages of dry matter and lower percentages of ash, and that the calcium content of the ash is much higher, while the percentages of potassium and sodium are much lower. Data, presented in tabular form, tend to show that the soils associated with chlorosis contain high percentages of carbonates Cracking. Fromme por a a rather widespread cracking of apples in Virginia, especially on the Stayman varicty. The trouble evidently was induced by heavy rains. He states: "We assume that this phenomenon is similar to the crecking of cherries in which osmotic prawesses are set into motion, resulting in sufficient. pressure to cause a rupture of the skin." Schneiderhan reported that York Imperial, Winesap, Rome Beauty, and King David were affected also. Corky core. In describing this trouble, D. F. Fisher says that it occurs locally in Washington but is of slight importance. It occurred where there was | e deficiency of soil moisture and apparently was favored by a high temperature... It was more or less general where there was a shortage of irrigation water or Where soil conditions were such that trecs could not get adequate moisture. The Rome, Delicious, and Jonathan varieties were susceptible. The effect on the tree was premature ripening and dropping of the fruit. It seems that the disease is generally more prevalent in the Okanogan Valley of British Columbia than in. Washington. Cork, drought spot, and drought die—back. “ Hewe Yorkow! nbs only in the Champlain V Valley, affecting chiefly the Fameuse and McIntosh varieties. The 1926 loss amounted to 1 per cent of the crop on these varieties. In Clinton County © cork and draght spot are the chief concern of most growers. In 1925, these ap- parently releted troubles. anit 4 es marketable crop one-half in seh hn orchard ; (Burrell). oi ¥ trial *) i \eted2 al odd to ygoigid of } . Drought die-back. Mills yr Burell of New York say that this trouble | own to occur in New York only in the rida Valley. It was less sev ' | 1925+ They consider that cork, drought spot, and drovht die- ptoms prodiced by a common cause. Burr states "Die-back is associated with cork and drovg ht Xe Vv s found to some extent on the fao-beet Prope 43 Apple ~ Ree tinmpedbeis Dis cases more or less irregular lanes ieee ‘of ee eeniitea dp region can often be nnerd back into three-year old wood." . Drought spot. Also occurs in ie estes Champlain region of New York on Mcintosh and Northern. Spy+. The loss in Clinton County in 1926 was estimated at 5 per cent of the commercial crop. A 30 per cent loss was found in one 90 acre orchard. In Orwell, Vermont, about a,dozen trees were found with drought-—spotted fruit. Burrell states, "This disease can be found abundantly in some parts of the northern orchards in Clinton County, New York, where it is not known to have occurred previously. It occurs on trees that’ are large and vigorous as well as on trees that are small and stunted. It occurs on trees that show die-back and on trees that do not. The first drought spot lesions discovered in 1926 occurred on a McIntosh tree which showed considerable die-back of the terminal twigs. The external symptoms as noted on fruits 1-1.5 cm. in transverse diameter are, a brown band in the epidermis, partially encircling the apple near the calyx end with many Minute droplets of an amber-colored fluid exudate scattered over the surface of the lesion." Anderson reports the disease to be serious in ee Illinois and Barss States that unusually dry weather in Oregon was the cause of considerable trouble. Incompatibility with black walnuts. Schneiderhan, in reports to the Plant Disease Survey, calls attention to the incompatibility between apple trees and black walnut trees when growing closely enough to pemit the intermingling of the roots. He states; “Bighteen instances have been noted. Measurements of dis- tances between the walnut and apple have been completed in 16 of the cases. A total of nineteen walnuts were found to: have caused the death of 49 ad the dwarfing. of 10 apple trees. The maximum distance at which a tree was killed by the toxic substance given off by the walnut roots was 75 feet and the minimum distance was 16 feet. The average distance at which death occurred was 33 feet and the average distance at which they were dwarfed was 40 feet. In only one instance was an apple tree found to function normally within the average border of the toxic court. This was a Stayman tree 30 feet from a large walnut. The irregularity of the direction of root growth of the walnut my account for this exception. English walnuts do not cause injury to the apple." Internal breakdown. > Bunncidaphan reports the trouble to have been preva- in Virginia on Duchess and Ben Davis apples. The cause of the trouble is a oe the oe. low rainfall late in, the season. i, a] ing Was reported from California as the cause of a 4 per Cerne eres according to Fromme, this disease was responsible for the on of 100 trees in an orchard. Archer reports the disease to be of e in Southern Missouri. again reported by Mills from New Vorke Ss reported to be slightly important in Idaho and Washington. sis ibaa ee in Washington. 44. Apple - Non-Parasitic Dis cases: Stigmonose induced by the box.elder bug cau sed “some damage ‘in a few or-— chards in Washington, according to Fisher. The Rome variety seemed to be es— pecially preferred. The crop was completely ruined on some trees. The insects were Quite gregarious, confining themselves to certain trees and often to the sunny side. The feeding punctures praluced brown spots just below the skin of the apple. ; Water core Was present to a slight extent in Missouri on Early Harvest and in Michigan on King and Northem Spy. In Indiana some of the younger trees of lp aeiecticaed eg and Duchess showed as high as 75 per cent water core. Brooks and Fisher (1) state that irrigation’ exper iments show tha t apples from lightly irrigated trees develop -more water core than those from heavily irri- gated trees: An excess of soil moisture did not increase the anount of injury. Nitrate and potash fertilizers’ seemed to reducé'the amount of injury+ They be- lieve that the disease is the result of’ sap exudation under pressure and that high sap concentration is a precursor of the disease. Sun _ scald of apple fruit was reported from New York, Connecticut, and Delawaree In the last named state, Adams reports that the injury was more se- vere .than ever before and that 20-por cent of the Stayman variety was affected. Mae ~ Recent literature 1. Brooks, C., and D. F. Fisher. Water core of apples. Jour. Agr. Res. 32: 223-260. 1926. 2. Detjen, L. R. Physiological dr opping of fruits. Delaware Sta. Buls. 143: 5-47. 1926. 4. Granovsky, A. A. . Studies on leafhopper injury to apple leaves. Phytopath. 16: 414-422. . June 1926. 4. McClelland, N., and L. W. Tiller. Cool storage investigations in _ New Zeland. Season 1925. Fruit Worid of Australasia 27: — 179-184. 1926. ; 5. McLean Thompson, J. Some general problems of the transport by see and conservation in store of ripe fruit. Jour. R. Soc. of Arts 74; 328.541. 1926. 6. Oskemp,-J*. Apple scald. Proc. New York State Hort. Soc. 1926 (7lst Ann. Meet.): 191-196. 1926. 7+ Plagge, He Soft scald end breakdown of apples as abe eee by storage temperature. Proc. Amer. Soc. Hort. Sci. seg 58-66. 1926. O. and T. J. Maney. Cold storage investigations with Wealthy Apples. Fifth Progress Reports Iowa Agr. Exp. Sta. Bul. 230: 59-72- 1925. Effectiveness of oiled wraps in the control of storage diseases of apples. Bienn. Rep. Kansas State Hort. Sec. 38 (1924-25): 155-157. 1926. Apple - Non-Parasitic Diseases A5 Pear — Blight 10. Reimers, Ke Funktionelle krankheiten bei Ktihlhauseepfeln. Obst- u. Gemtiseb. 72: 235-237. Ang teas ll. -Wallace, Re H. The prodiction of intumescences upon apple twigs by ethylene gas. Bul. Torrey Bot. Club 95% 305- AOL. June 1926. 12. Wallace, T., md C. HE. T. Mann. Investigations ‘on chlorosis of fruit trees. I. The composition of apple leaves in cases of lime-induced chlorosis. Jour. Pomol. end Hort. Science tern 112, 19°65, ; PLULAR igs BLIGHT CAUSED BY BACILLUS AMYLOVORUS (BURR.) TREV. In 194, as in “previous years, blight was reported from practically all pear-growing districts. The majority of collaborators reported the prevalence to be the same as last year and as the average year. However, Delaware, Connecticut, Pennsylvania, Illinois, and Indiana reported more than usual, while New York, Arkensas, Arizona, Colorado, and Washington reported a aa The losses reported for 192 are given in table 15. The DORI reports of collaborators indi cate the nature of damage oc- curring in 1926. New York: Some orchards have been badly damaged this year. There was only a slight emount of blossom blight but late infection occurred through the twigs. (Barrus) Virginia: H#astern Shore Section - Blight has practically eliminated pears from home’ orchards. Severe infections. were common in tne southern peninsula. (McWhorter) Tennessee: Outbreak was later than usual, perhaps due to dry and cool spring. By May, however, the blight was widespread in eastern Tennessee. (Hesler) Arkansas: For the first time in a number of years there was a good crop of fruit and very little blight. (Dept. Pl. Path.) Ohio: Especially severe in saithern and southwestern Ohio With infection extending northward. (Thomas) Indiana: Serious mainly as a smrce of infection for apple orchards. (Gardner) | Pear — Blight ’ Kansas: Severe in scattered localities in southeastern and eastern portioris of state. (White) Arizona: Blosson blight severe in northern part of state, ° (Brisley) Washington: Only traces of blight were observed in the eastern part of the state. The dis case was partiailarly active last sedson and considerable hold—over' blight Was observed early this spring. (Dept. Pl. Path.} California: Growers succeeded in stopping the spread of blight which caused serious losses last season. (H. A. Harris) The sterilizing solution used in Los Angeles County consisted of mercuric chloride 4 tablets, mercuric cyanide 4 tablets, water 1 pint, glycerine: 1 pint. (Cc. R. Gorton, Deputy County Hort. Comn. ) The following represents the scant data on varietal resistance: In Dela- ware it was very prevalent on Keiffer (Adams)e The Sand Pear, considered to be resistant, sometimes suffers severely in Florida (West). At the Stark Nursery in Missouri all varieties were severely blighted except Surprise (Archer). In Michigan the Keiffer was resistant and the Bartlett very susceptible (Bennett). Reimer (2) reporting on spraying tests, states that Bordeaux spray ap-— plied at the proper time will materially reduce the number of blight infec- tions, although russeting of the fruit will occur when spray applications are followed by continued rains. The pink or pre-bloom application was found to be the most effective, although there was evidence that later application also had vaine. Spraying with Bordemx mixture is to be regarded strictly as sup- plementary to the other work of root inspection, eradication of cankers and blighted branches, etc. . Table 15- Percentage losses from pear blight, as estimated by collaborators, 1926. Percentage: ; ::Percentage: loss States reporting 2 loss :States reporting 75 : Louisiana =! ay : Arizona 40 : Mississippi ce: ge : Connecticut, 40 : Arkansas -f : Delaware, Texas, 2A) : Tennessee 5 : Kansas 20 : North Carolina 2: 1s : Ohio iy : Missouri ss 1 : Virginia, West 10 : Illinois, Towa — a Viren 8 : Maryland 2. araee : New Jersey, Wisconsin, 5 : Michigan, South = : Idaho, Washington, Dakota, Californie ss : Oregon AY Pear - Blight; Scab Recent literature 1. Nixon, E. L. Fire blight.. Permsvivania Agr. Exp. Sta. Bul. 20g se22e" "June" 1926" 2. Reimer, F. C. Value of Bordeaux mixture in blight control. Seventeenth Ann. Rept. Oreg. State Hort. Soc. p- 1-7. Dec. 1925. SOR ere Eb bts 3. Rosen, H. R. The number and arrangement of flagella of the fire blight pathogen, Bacillus amylovorus. Mycologia 18: 23-26. Jan.-Feb. 1926.. noe i | SCAB CAUSED BY VENTURIA PYRINA ADERH. Apparently scab was relatively unimportant in 1926 since its occurrence Was reported only in 13 states and.of these only 10:gave estimates of losses: © New Jersey, 5 per cent; Maryland, Wisconsin, Oregon, and California, each 1 per _ Cent; Ohio and Connecticut, each 0.5 per cent; Michigan, Delaware, Virginia, and _ West Virginia, a trace. New.York, Pemsylvania, Iowa, and Washington reported the disease to be present but gave no estimates of losses. Connecticut, New York, Pennsylvania, Maryland, Ohio, Illinois, Iowa, and Washington report less preva- | dence in comparison with a normal year. New Jersey, Delaware, Michigan, and _ Wisconsin report average prevalmce. x ie Some of the reports of collaborators follow: | New York: Although reported as present in many counties” . in the eastern and western parts of the state, the disease has ae caused practically no damage. The dry: cool spring and early | summer is probably responsible for this condition. (Barrus) Pennsylvania: Occurrence very slight. Least on record. (Thur s ton) Washington: Scab occurred only in slight amounts in western part of state. (Dept. Pl. Path.) Oregon: Present throwhout western portion of state but by n) means aS severe as in 1925. (Barssd Ms A few reports were received on varietal susceptibility as follows: _ Flemish Beauty in Michigan; Clapp Favorite, Anjou, and Flemish Beauty in New York; _ Sheldon and Flemish Beauty in Connecticut reported as susceptible; Bartlett and Kei ffer in Michigan reported as resistant. a LEAF BLIGHT CAUSED BY FABRARA MACUIATA (LEV.) ATK. The records of the Plant Discase Survey show that practically all the reports of this disease have come from areas e4st of the Missouri River, with most of the reports of important losses coming from New York, Pemsylvania, New Jersey, Delaware, Maryland, end Ohio. In 1926 only eight states reported losses as follows: New Jersey and Maryland, 5 per cent each; Temessee, 2 per cent; Delaware, West Virginia, Arkansas, Illinois, and Michigan, a trace. In Delaware, Adams reports that there was heavy leaf infection on neglected trees. In Georgia, Higgins reports that the disease did not appear although it is usually serious on most varietics of pear. The Departmemt of Plant Pathology in Arkansas re- ports that it was abundant on French secdling pears, defoliating the trees in September. MISCELLANIOUS PARASITIC DISEASES Armillaria mellea (Vahl) Quel., root rot. Washington. Brovm blotch (undet.) ~ Occurred commonly on Keiffer and slightly on Bartlett in Missouri. (Archer) , Bacterium tumefaciens EFS. & Town., crown galle One report in Conrecticut on nursery stock imported from France. (Clinton) Fumago vagans Pers. Occurred as a sooty mold following plant lice in Connecticut. (Clinton) _ " . ; Gymnos orangium globgsum Farl., rust. Connecticut and Florida. Gymnospo rangium kernianum Bethel rust. 100 per cent infection of the fruit on one tree in northem Arizona. (Brisley) Leptothyrium pomi (Mont. & Fr.) Sacc. and Gloeodes pomigena (Schw. ) Colby, fly speck and sooty mold. Occurred quite commonly in Missouri. (Archer) Mycosphaerella sentina (Fr.) Schroet., leaf spot. In 1926 reports of losses were received from Tennessee, 2 percent; Marylam, Illinois, and Michigan, a trace each. In addition the disease was reported to occur in New York, Virginia, and Indiana. Nectria galligena Bres. Reported by Dililon-Weston (2) as an "eye rot" of pears. Qzonium ommivorum Shear, root rot. Prevalent in black lands of Texas, causing a loss of 2 per cent. (Taubenhaus). 2 per cent loss in Arizona. : Physalospora malorum (Pk.) Shear, black rot. Losses were reported in 1926 from Maryland, 5 per cent; Tennessee, 1 per cent; Illinois and Michigan, a trace each. In Delaware fruit infection was prevalent on ljate harvested fruit. In Arkansas it was reported as slight on fruit. In New Jersey injury to tips of new shoots Was observed ‘in one orchard. In Missouri two small collections were made, one on leaves and the other on twigs. Phytophthora cactorum (Leb. & Cohn) Schroet., fruit rot. Indiana. 49 MISCELLANEOUS NON-PARASITIC DISEASES Bitter pit - Reported from Washington. Black-end rot. Caused a oH per cent loss in California. (Milbrath). Also present in Washington. Heppner (4) describes black-end rot or hard-end as a serious trouble, evidently physiological, which has been causing enormous losses to the Califomia Bartlett pear industry for the past several years. It has been observed in practically every pear growing section of the state, such as the Antelope Valley of Los Angeles County, the Sacramento River section, and Mendocino, El Dorado, Contra Costa, Lake, and Napa Counties, and reports have come also from other sections where the Bartlett pear is produced; so apparently no pear prodic- ing section of the state is entirely free from it. In preliminary investigation to determine the nature of the disease, careful records were kept of the fruit ‘as harvested from each tree in twelve orchards in various parts of the Antelope “Valley. Of the trees on Japanese roots 70 per cent produced fruit with black-end, while none of the trees on French roots produced such fruit. About the sane re- sults were obtained in observations in other sections. A very few isolated trees on French roots were found bearing black-end fruit, in each case in soil which ‘Was excessively wet in winter and extremely dry in summer. Conclusions cannot be drawn until more work has been done. Chlorosis (excess of limc) — Traces in Texas. (Tau benhaus) Exanthena ~ Two occurrences reported in California. (H. E. Thomas ) Frost injury - Michigan reported a 0.5 per cent loss; Arizona and bei “atrace. In Washington the injury was said to be important. Hail injury - In South Carolina, according to Ludwig, affected 85 per cent @2 the crop. . Leéf scorch ~ Caused probably by atmospheric desiccation was moderately importent in Washington. The demage occurred during a period of high temperatures with freqent drying winds. The Bartlett was resistmt, while Anjou and Bose were susceptible. (Fisher) Rough bark — Reported in Washingtons (Dept. Pl. Path.) Recent literature 1. Barnard, L. C. Little leaf of pears (lake County conditions). Galetomia Cult. 67 (1): 8. July 192. 2. Dillon-Weston, W. A- Re An "eye" rot of pears. Gard. Chron. i, 80: 375. Nov. 1926. 4. Harrison, J. BE. Cold storage of pears. Fruit World of Australasia 27: 30-32. 1926. 4e Heppner,’ Myer J. Bartlett pear black-end rot investigation. Califomia Pear-Grover 6 (9): 5-6. 1926. Hawemedler,) Si) Me A blossom and spur blight of pear caused by a strain of Botrytis cinerea Pers. Jour. Agr. Res. 43: 477-482. Sept. 1926. 50 Bacillus amylovorus (Burr.) Trev., fire blight. The losses reported by collaborators for 1926 were New York, 5 to 10 per cent; Marylend and Michigan, each 5 per cent; Texas, 1 per cent; Virginia, a trace. _The disease was ‘said. to be important in Ohio and New Jersey, and only slightly important in Pemsylvania, Delaware, Termessee, South Caroline, Florida, and Indiana. Fabraeca maculata (Lev. A ie eee iaen te Reported from Tennessce with loss of 2 per cent; Michigm, l-per cent; New York and Maryland, each « trace. Also reported to occur in Connectimt, lege Sou th ‘Carolina, and Florida. Gymnosporangium germinale (Senn Kern, rust. oss in Maryland, 5 per cent; and in Michigan and Virginia, « trace cach. Also slight occurrence re- ported in New York, Connecticut, Ee ES Haas New Jersey, South Carolina, and North Carolina. Glocodes pomigena (Schw.) Colby, he blotch. Found plentifully both _on harvested quineces and on fruit on the trees in Missouri. Superficially and microscopically the fungus hes the appearance of the sooty bleteh fungus, althouch there were no fruiting bodies. So far as could be determined there seems to be no reference in the literature reporting this fungus on quince. (Archer) Physalospora malorum (Pk.) Shear, black rot. Reported from Indiana and Connecticut. “ay: 2 Recent litcrature 1. Wormald, H- On the occurrence in Britain of the conidial stage of Sclcrotinia cydoniae Schcll. Trans. Brit. Myc. Soc. 10: 403-306. eb. 25, 1926. DTS aes Et Oey SP ONL Sy lt Re Ue AS BROWN ROT CAUSED BY SCLEROTINIA FRUCTICOLA (‘7INT.) REHM. This discase is widespread in all the principal peach growing districts of the United States. Since 1918, according to records of the Plant Disease Survey, the heavicst percentage losses have occurred in South Carolina, with an average loss of 24 per cmt; Florida, 18.5 per cont;.Georgia, 12-5 per emt; Kentucky ond Mississippi, each 11.5 per cent; Pennsylvania, 10.9 per cent; North Carolina, 10.2 per cent; Delawarc, 10.1 per cent; Maryland, 9.8 per cent; Alabama, 9-7 per cont; New Jersey, 7«1 per cent. The losses for 19 26 are given in table 16. The prevalcnce of Gaacas rot in 1926 was the same in comparison with the average yvar in New Jersey, Tennessee, Alabama, Mississippi, Louisiana, Iniians, Missouri, and Kansas. It was said to be more prevalmt in Delaware, Maryland, and Michigan; while it was less so in Connecticut, New York, Pemsylvenia, Vir-— ginia, North Carolina, South Carolina, srkensas, and Tllinois. Peach = Brown Rot. The following data on the observance. af the first mature apothecia are presented: as Georgia: Apothecia were nok, plentiful but a few were observed in the orchards towards, the end. of March. (Dunegan) Arkansas: Eee eee Sunde ‘around Fayetteville. (Dept. Pl. Sie yo | Illinois: ‘Apothecia we re pipeee cs in old plum thickets and under peach trees which had not been cultivated. A few were found in the region of Collinsville in qltivated peach orchards. In general, however, apothec ia wer e not common in well kept orchards. (Anderson) Indiana: Active apothecia found in Knox County, April 21, under seedling trees. (Gardner ) Connecticut: Some rot on early varieties, but little on late varieties compared with most-seasms. (Clinton) New York: One orchard of Rochester peaches showed severe injury to the branches which appears to be caused by brow rot. Other varieties in the same orchard seen to be free from the injury. (EB. E. Frane) Delaware: The first infection was.found on Early Rose. Harly varieties in general showed heavy infection. Infection on Carman followed peach moth infestation. oes) Georgia: Blossom blight first seen on. ish ae. Scattered infections were observed on Mayflower, Red Bird, Carman, Uneeda, and Hiley, but the disease did not become prevalent. he a result it was possible to successfully harvest the early varieties. (Dunegan) ~ Mississippi: Very severe on early varieties due in part to injuries resulting from a heavy hail stom and a wet spring. (Wedgw or th) The relation of weather conmlitions to the development of brown rot is discussed in the following remarks by collaborators: Illinois; Browm rot was almost absent from fruit this year because of two factors. Curculio was extremely rare and weather comitions were unfavorablé for the developmmt of the disease up to the time of harvesting. The wet weather during harvest might have caused heavy losses but for the fact that growers had sprayed 51 52 Peach — Brown Rot unusually carefully and had thinned their fruit more than usual. The cracking of the fruit as a result of heavy rains following extreme dry weather in southern Illinois would have been a serious factor so far as brown rot was concerned had the spores been abundant in the orchards. Some brown rot developed in transit and in the market, but it was mich less than expected. (Anderson) Oregon: Abundant ee: ;and dry atmospheric conditions pre- vailing through March and April were rather unfavorable for spore fomation and infection. There was considerable loss in some orchards. Little spraying done. (Barss) Ohio: The weather during late August and early September was favorable for development of the eee. but spraying held it in check. (H. C. Young) South Garo] inn: With relation to the dry weather, which existed during the summer, it might be said that brown rot was less trouble- some than in any other year. The result was an unusually large crop which caused the price to drop almost to the no-profit point. (Iudwig) North Carolina: A deficiency of summer rainfall retarded the disease. In the Sandhills sections, where orchards were well sprayed, the disease was less prevalent than in other parts of the state. (Fant) Delaware: Evidence indicates more fruit infection than has been experierced for five years. Aboe normal rainfall during July with humid weather favored infection. (Adams) Table 16. by collaborators, 1926. Percentage losses from brown rot of peach as estimated Percentage: ::Percentage: loss :States reporting ce loss :Otates reporting 25 : Louisiana tec BS 19) : Maryland, Missouri By LO : Michigan < 2 8 : Alabama a 6 : Arkansas =< 1.5 D : New Jersey, Tennessee, : as North Carolina, 2: 05 : Mississippi =< ol A : Ohio ::. Trace : Connecticut, West Virginia : Delaware, Indiana, Oregon : Virginia South Carolina, Kansas : New York : Califormia : Texas, Illinois Recent literature le Anon. Spray calendar for peaches. New Jer sey Cires 181: 1A. 1926. eh Do Peach ~'’Brown. Rots Leaf :Curl 2. Anon. Control of brown rot in stme fruits. Recent experiments at ae New Zealand. Jour. Agr. 45: 170-174. Sept. 4. Roberts, J./W., and d. Co Dunegan. Blossom blight of the peach. Phytopath. 16: 217-222. Mar. 1926. 4. Schneiderhan, F.-J., and R. H. Hurt. The dry-mix spray for peaches. Virginia Agr. Exp. Sta. Bul. 239: 1-16. 1926. IEAF CURL CAUSED BY, EXOASCUS.DEFORMANS (BERK.) FCKL. Records of the Plant Disease Survey would indicate that leaf curl has been reported from all states except Vermont, Wisconsin, Minnesota, North Dakota, South Dakota, Montana, and Wyoming. According to collaborators' reports since 1916 the highest percentage losses have occurred in Oregon; 4. 8; Maryland, 4.2; Kentucky, ha 6; New York, 4-5; Permsylvania, 4; eae oe 2. th Arizona, 2's oe and oun, eel; and Michigan, 2. : In "1926 it would seem that the, nee Stottred aS an epidemic in Arkansas, Illinois, Indiaa, Missouri, Mississippi, and Louisiaha where it was reported to be more prevalent than usual or than last year.. Edgerton reports the occur- ‘fence of the disease for the. first time in Louisiana. He states that there was apparently an epidemic on young trees. in all the northern part of the state. The first occurrence is recorded from Utah also by B. Le Richardse He states; i "The disease was found in a severe form in the Bear River Canyon District. Two orchards were. damaged to the extent of from 60 to 75 per cent of the crop. The almost complete defoliation of the trees at the late date of July indicated that the trouble may become a serious factor in peach culturé in the state." A collaborator's report in the files of the Plant Disease Survey states that the _ disease occurred slightly in Utah in oe but evidently it has nok been reported meince that time. The reports on losses for the United States are given in table a7. and the dates of earliest appearance in table 18 Following are extracts from the reports of collaborators: Massachusetts; Infection:very light in orchards which reccived a dormant spray. (Osmun) Connectiat: This discase is now seldom reported. (Stoddard) New York: Only slight amounts noted. (Mills) New Jersey: Reported only from north Jorsey. (Martin) D4. Peach ~ Leaf Curl Georgia: Duc to the late scason and severe cold in last of March and early April, deaf, curl hes, been serious in some parts of state. (McHatton) Mississippi: General as the result of cool wet weather in spring. (Bvalc) Texas: Epidemic duc to late cold wet spring. (Taubenhaus) Arkansas: Perhaps the most outstanding discase this spring. Extremely prevalent, causing severe defoliation of unsprayed and poorly sprayed trees. Weather extremely favorable for the devclop- ment of the disease during spring. (V. H. Young) Ohio: Of no importance this year. Few scattering cases. (He C. Young) Indiana: Serious in orchards not properly sprayed. Lesions noted on fruits. (Gardner) Tllinois; The outstanding disease of peach this season was leaf curl. It is safo to say that this was the worst outbreak of this disease which we have expericneed for a decade. The outbreak was unexpected since no leaf curl was observed the previous season in the region where it was most severe.this ycar. As & result of the conditions this year we hive learned that there is no way of fore- ‘telling epidemics of leaf curl, am the only way to protect the orchards is to spray in the fall with a fungicide which we know will control the disease. It is not safe to wait until spring. The belt where the disease was most severe extended from Carbondale northward to Neoga with the severest infection in the Centralia region and castward. Some orchards were completely de- folic ted and so weakened that they did not sct a crops Where nitrate was used promptly some orchards recovered sufficicntly to produce a fine crop. The cause of the unusual outbreak this season wes the prolonged cool weather during April following a warm period in March which started the buds. Also, growers had not been able to apply the sprays carly in the spring due to unfavorable weather, and @ great many orchards werc either spray ed too late or were spreyed with oil emulsion. (Anderson) Michigan: Common over the entire state on unsprayed trees. (Bennett) Missouri: Most severe infestation in 15 years. Severe all over state in unsprayed orchards. Severe defoliation occurred in parts of the Ozarks resulting in total loss of fruit in many small orchards. (Archer) 5 Peach - leaf Curl ° The following few reports of collaborators indicate the nature and effective- ness of control measures: Tllinois: It was noticed that where Bordeaux mixture had been used with oil emlsion that very good control had been se- cured. In one orchard oil emulsion alone had been used on part of the orchard while oil emulsion plus Bordeaux had been used on the remainder. Although the spray had -been applied after the buds began to swell, fairly good control had been secured. Orchards which had had consistently good care both as to pruning and fertilization in former years although sprayed with Oil alone did not suffer as much as those which had not received this care. It is not known why this’ should make a difference but it was evident in several sections. (Anderson) Maryland: Severe in all unsprayed orchards and also where dormant application was mde after the buds began to swell. In -one orchard check trees hed 95 per cent leaf curl and trees which were sprayed while domant with concentrated lime-sulfur (1-9) had only 5 per cent infection. (Jehle). Tennessee: Very prevalent where dormant spray with fungicide was omitted. (Boskin) Georgia: Orchards well sprayed with concentrated lime-sulfur during february have shown little infection. (McHatton) Alabama: Unsually severe where only winter spray or oil spray was given. (Miles) : Arkensas: Many growers are apparently dispensing with a fungicide in the dormant spray, since lubricating oil emulsion has displeced lime-sulfur as a scalecide in many cases. This omission of the fungicide is risky, as demonstrated by the severe infestation of le.f curl this season. (V. H. Young) Table 17. Percentage losses from peach leaf curl as estimated by colleborators, 1926. Se en eee Percentage: ::Percentage: loss :States reporting loss “States reportin a) : Missouri 3 wal : California 2 : Maryland, Tennessee, :: Trace : New York, New Jersey, ; Arkansas i : Delaware, West Vir- fi feo 9; Nortn Carolina, Alabama ~’:: : Pinta, Georgia. i 1 : Illinois, Indiana, oie » louisiana, Michigan, Kansas oe > , root rot. Occas ional ‘trees in many or- hards of California. (Thomas) Coccomyces prunophorae, lig. leaf spot. New York, Delaware, Maryland, Arkansas, Ohio, Michigan, Wisc msin, Minnesota, Missouri, and Oregon. Losses were reported as a trace in Maryland, Ohio, Michigan, and Minnesota. Phyllosticta prunicola Sacc., leaf gover In Missouri 100 per cent in one locality. (Archer) Phyllosticta virginianae (E. & H.) Seaver, leaf spot. Towa. Im nursery on Hansen variety. (Archer) Plum — Miscellaneous Diseases 69 Cherry -— Brown. Rot Phyllosticta sp-, plum blotch. Texas; traces. (Taubenhaus } Tranzschelia pruni-spinosae (Pers. ) Arth., rust. Texas. Chlorosis due to excess of lime. Texas. Exanthema (cause unknown). Present in the Santa Cruz Mountain District of California. (H. BE. Thomas) : Internal browning and shrivel (non-parasitic). Reported from Wasco County, Oregon. Little was noted in Willamette Valley where it is often serious- (Barss) Recent literature 1. Brooks, F. T., and W. C. Moore. Silver-leaf disease. V.- Jour. Pool. & Hort. Science 5: 61-97. 1926. 2. Carne, W.M. Crinkle of Japanese Plums... Jour. Dept. Agr. Western Australia 2nd Ser. 3 (2): 175. 1926. Se eWwarbrick, Ts The healing of wounds in woody stems. Jour. Pomol. & Hort. Science 5: 98-114. 1926. Cull Gee Be Ys BROWN ROT CAUSED BY SCIEROTINIA FRUCTICO LA (WINT.) REHM. -Reports of brown rot on cherries in 1926 came from the Middle Atlantic _ and the Ohio Valley States, as well as from some of the Middle Western, most of Hythe Great Lake States, and the Pacific Coast Stetes. Apparently there was less than usual, only Virginia, Tennessee, and Califomia reporting more. The losses for 1926 are given in table 22. In Oregon Barss states: "At harvest time, which was three weeks in ad- Vance over the average season, some brown rot showed in all wéstern Oregon or- Chards but not enough to cause severe losses on the trees except in case of Bing Cherries which cracked from rain and became badly rotted afterward." In New York, ) according to Mills, brown rot following curmlio injury caused considerable loss ato some growers in Ulster County. In Virginia, Schneiderhan reported that worm injury and moist weather during ripening season increased the infection. Table 22. Percentage losses from brown rot of cherry, as estimated by collaborators, 1920. Percentage; ::Percentage: loss _ :States reporting sass loss :Otates reporting % ; Maryland 2: 1 : West Virginia, 5 : New Jersey, Tennessee:: : Fillinois, Califemaia G) : Virginia, Arkansas, :: =) : Ohio, Wisconsin Michigan 5: .crace : New York, Delaware, a : Oregon side : Lowa, Kansas, 1 : Connecticut ae : Washington Pi Recent literature {0 Cherry IBAF SPOT CAUSED BY COCCOMYCES HIEMALIS HIG. In 1926 the leaf spot of cherry occurred in scattered states although it Was mostly confined to the Middle Atlantic and Ohio Valley States. Evidently the disease was not important this year since, of the 17 states reporting on comparative prevalence, only 4, New Jersey, Maryland, Virginia, and Missouri, reported it to be normal, and Connectimt alone reported it to be more than normal. Losses for 1926 were reported from Maryland and Missouri as 10 per cent; Michigan and Arkansas, 2 per cent; Virginia, Tennessee, Towa, and Montana, 1 per cent; Wisconsin, 0.5 per cent; Yest Virginia, Tllinsis, Kearsas, and Oregon-e LYace. Ws In New Jersey, Missouri, and Arkansas complete defoliation occurred in many cases where sprays were not applied. In Delaware it was generally prevalent but no heavy defoliation occurred. In Wisconsin the disease was controlled with lime-sulfur and in Temess see with Bordeaux mixture. : BACTERIAL SPOT CAUSED BY BACTSRIUM PRUNI EFS. Bacterial spot on cherry was reported from two states only in 1926. In New York it was said to be the cause of much dropping of leaves in one county. In Missouri it ceused defoliation of trees in some parts of the Ozarks and it was also found several tims causing severe leaf spotting of.nursery stock. BACTERIAL GUMMOSIS CAUSED BY BACTERIUM CERAST GRIFFIN Bacterial gummosis was reported from Washington, Oregon, and California. -In Californic, according to Goldsworthy, gummosis is a more or less chronic con— dition in cherries. Many limbs are lost each year, although not many trees are affected. The fruit is usually harvested before wood losses occur. Losses duc to. the disease cannot be estimated, but it was of moderate importance in 1926. In western Oregon, according to Barss, the disease is causing less damage than formerly, due to the fact that many growers sre resorting to seedling stock for Dedies, to Which limbs are graftcd later. Sackett (1) reports on a new bacterial dis ease of the Wragg cherry, caused by Phytomonas (Pseudomonas ) cerasi wraggi Sackett. ‘The disease is cheracterized by brown spots on the leaves and b by watery, green (later black and sunken) lesions on the unripe fruit, which eventually becomes mummificd. t, W. G. Report of the Bactcriologist. 38th Ann. Rept. olorado Agr. Exp. Sta. for year 1925: 16-20. 1926. @et WL Cherry MISCELLANEOUS DISH ASES Armillaria mcllea (Vahl) Qudl., root rot. Reported: on an occasional tree in many orclimrds in California. Botrytis cinerea Auct., gray mold. Caused 1 per cent loss in Califomia. mxoascus cerasi (Pck1 -) Sadeb., witehcs' broom. Occasional in western Oregon. ; oe i Plowrightia morbosa (Schw.) Sacc., black knot. Although widespread this disease was reported only from New Jersey, Pennsylvania, Virginia, Missmri, and Idaho. It was not mentioned as of economic importance in any of these states. Podosphacra oxyacanthae (DC.) D By., powdery mildew. Reported from Missouri, Towa, Wisconsin, Indiana, and New York but the disease was considered to be important only in Fowr vhere the loss wes reported as 4 per cent. Recent literature ls Faces, H., and Stachelin. Les ma ladics des ceriSicrs au printemps 1926. Terre Vaud. 16: 421-415. July 1926. 2. Gray, W. P. Spraying and harvesting the cherry crop. Ann. Rept. State Hort. Soc. Michigan 55: 21-24. 1926. 54- Ross, W. A- Sour cherries injured by Bordeaux. Canada Hort. A9; 23. Feb. 1926. Ais) Lubeur, Carl von Auftreten der blattbrfune der stisskirchen durch befall von Gnomonia erythrostoma aa Hee ech Peau (Rheinpfalz). Zcitsehr. Pflanzenkr. 36: 237-258. 1926. Sw2oR T ClO 0 . Armillaria mellea (Vahl) Quel., root rot. Occasional tree killed in California. Bacillus amylovorus (Burr.) Trov., fire blight. Loss a trace in Texas. Bactcrium corasi Griffin, bactcrial gummosis. In Califomis the disease is chronic in all apricot regions. Apparently the infected trees produce as well es Dealthy ones, but the life of a discascd tree is considerably shortened. (Goldsworthy ) Bacterium pruni EFS., bacterial spot. Reported from Texas and Missouri. Bacterium ace ee HES: 3icrown Zalle hess. 2 tpeleJeent ini Wrizona. Cladosporium ¢ carpophilum Pauiems, scabs Texas. oss Ohh per eccnte Coryneum beijerinckii Oud., blight. Reported from Califomia, Oregon, Washington, and Idaho. In Idaho there was an unususl amount of the discase due to the neglect in spraying last year on account of a severe freeze which killed all the San Jose Scale. (Hungerford) Apricot - Discases Grape ~ Black Rot Coccomyces spe, leaf spot. Texas. Ozonium omnivorum Shear, root rot. Loss 1 per cent in Arizona. Sclerotinia fructicola (ilint.) Rehm., brown rot. Reported from Weshington and Connecticut. Losses negligible. Chlorosis duc to too much limes Trace in Texas. Exanthema (cause unknown). Occurred in one district in California. Loss a trace. ip) DT Sw hein se SwveOr EuS) Me B Jil | abel Gime BLACK ROT CAUSED BY GUIGNARDIA BIDWELLII (BLL.) VIALaA & RAVAZ Of sixteen states reporting on black rot in 1926, seven, Maryland, Tennessee, South Carolina, Wisconsin, Iowa, Missouri, and Kansas, reported the average amount; five, Connecticut, Pemnsylvania, Michigan, New York, North Carolina, and Illinois reported less; while only one, Virginia, reported more. The losses for 1926 are given in table 2%. General remarks of collaborators are given below: North Carolina: In an average> year black rot is important on fruit of the bunel grape but it doves not'oceur on fruit or the muscadine grape. (Poole & Fant) Arkansas: Very important where spraying is not well done. Always present in home vineyards. Noted also on vinifera type. (Depts Pl.’ Paths) Missouri: Particularly serious in southern Ozarks but is found to certain extent all over state. The Vergeens variety is especially susceptible. (Archer) Table 24. Percentage losses from black rot of grape, as estimated by collaborators, 1926. Percentage: : Percentage: loss rotates reporting los 10 : Maryland, Tennessee =e 2 : Delaware 9 : Virginia a i : West Virginia, A : North Carolina : “A : Wisconsin, Kansas 3 : South Carolina, Texas, ©: Trace : Illinois, Michigan, : Grape - Downy Mildew; Powdery Mildew 7. Schneider, G. A. Erfahrungen in der Rebschadlingsbekampfung. Nachr. tber Schddlings bekampf. (Formerly Nachrichtenbl. Landw. Abteil. Parbenfabriken vorm. F. Bayer & Co., Leverkusen bei Koln-am-Rhein) 1: 5-7. 1926. 8. Villedieu, G., and Mme. La composition et l'action des bouillies cupriques. Comptes Rendus Acad. d'Agrie. de France 12 (2): 65-70. 192. POWDERY MILDEW CAUSED BY UNCINULA NECATOR (SCHW.) BURR. In 1926 powdery mildew was reported to be present in Connecticut, New York, New Jersey, Pennsylvania, Maryland, Virginia, Texas, Ohio, Michigan, Iowa, Ari- zona, California, and Oregon. The losses reported were Maryland and California, 0.5 per cent; Virginia, Texas, Michigan, and Iowa, a trace. In Arizona the dis-— ease was especially severe in a large vineyard of Thompson Seedless- In Oregon it was gereral on Vinifera stock but was controlled by sulfur dust. D. H. Rose and W. S. Ballard have mede surveys in Califomia during 1925 and 1926, and re- port as follows on powdery mildew: "Powdery mildew was less surious in 1925 and 1926 than in 192A: and much less so than in 1924. Early in both seasons it caused some russeting of Malaga, Muscat and a few other varieties, about October 1, because of increased rainfall and cooler weather, the "active" mildew (live mycelium and spores) was found to a slight extent on the stems of the bunches in numerous viteyards of Muscat, Malaga, Emperor, Chanez and a few other varieties. On all of these peri- thecia in various stages of developmmt were found. "Hvidence was obtained from holding tests during both seasons that mildewed stems are very likely to be attacked in-storege or in transit by decay fungi, especially gray mold." Recent literature dhe Dubaquic, Je Le soufre colloidal contre l'oidium. Gironde Agr. et Vitic. 2 (15): 4-5. Mar. 1926. 2- Eyles, F. Two diseases‘of the vine. Rhodesia Agr. Jour. 23: 929-932. Oct. 1926. . 5+ Flossfeder, F. Grape mildew and its control. California Grape Grow. 7 (6): 6-7- June 1926. 4. Houston, H. Economy in sulphur. California Grape Grow. 7 (5): 14-15.- May 1926. —— en Grape (i BLACK MOLD ROT CAUSED BY ASPERGILLUS NIGER VAN TIEGEH. "In California black mold rot was found on all commercial varieties in 1925 and 1926 but caused most’ loss on Zinfandel, Burger, and Grenache Alicante Bouschet. The first two regu- jJarly and the third occasionally form bunches so tight that the berrics are often broken mrely by their pressure against each other in the bunch. The conseqient lcakage of juice’ furnishes a culture medium for the germination of the»spores of the mold and seems to be the min cause for occurrence of the decay in the varictiss mmtioned. Varicties which form loose, open bunches such as Malaga, Thompson Secedless, and Muscat were not found attacked by the mold” except Guring or soon after periods of rainy weather. Black mold rot was fairly common from. Modesto southward in the San Joaquin Valley, rare in the districts east of Los Angeles, and scored not’ to occur at ell north of Modesto or in Sonoma and Napa Countics. Tho rot was casily recognized. in the vineyard or an pack ing houses by the characteristic dark purplish-brovmm masses of spores. ‘These usually occurred on nests of two or three or a dozen or more berrics. In diseascd spots in the bunches where the fungus had been present for sometime, affected berries were dried up and much shriveled. Berries only recently affected were soft and leaky like those attacked by gray mold. "Tn transit the fungus scems to spread and devclop less than gray mold, for shipments ins pected at. the receiving markets rarely show much loss because of it. In one test made at Fresno in 1926, three bunches badly rotted by the mold were placed on a two-inch layer of sound bunches of Grenache grapes in a lug, and then cov- ered with more bunches of the same good qiality- At the ond of 10 days at 45 to 50° F. there was no sign of black mold rot in any but the three bunches which were rotten when the test began." (D. H. Rose and W. S. Ballard) ' GRAY MOLD ROT CAUSED BY BOTRYTIS SP. (PROBABLY B. CINEREA) "In Californie gray mold rot was found in 1925 in practically all of the vineyards visited in Sonoma and Napa Counties; it also egecurred, though to a lesser cxtent, in the territory around Sacramento and Lodi, mainly on Zinfandel, Tokay, and Alicante Bouschet. It was still less important at Modesto and could scarcely be found at all around Fresno and Bakcrsfield until the rains began carly in October. It is noteworthy that as here indi- cated gray mold rot was progressively worse from south,}#9,north and, as pointed out in the case of black mold rot that/discase was progressively worse from north to.south. Both were found at Modesto, which is roughly helf way between Bakcorsfiéld (Kern County) and Santa Rosa (Sonoma County). The distribution of the two probably depends on differences in temperature and humidity in the different sections. It is knotm at least that Botrytis is Grape ~ Gray Mold Rot; Frost Injury most prevalent in moist, cool temperatures like that of the Bay counties. A recent survey in Oregon by Schuster and Husman shows that in the grape growing regions of that state Botrytis is quite prevalent and. often destructive. These regions, it is scarcely necessary to point out, have a cool, damp climate. Anderson in 1924 reported Botrytis as by far the most serious fungous parasite in southeast Alaska which, as he also points out, has a climate characterized by mild winters and cool simmers accompanied by much cloudy and rainy weather. | "In 1926 the distritution of the rot was quite the eee of that found in 1925. The Bay counties had almost no rot of any kind and the southern sections (San Diego, Los Angeles, Ontario) an unusual amount in some localities and more in most localities than they had the year before. At some places in the south the increase in decay was thought to be due to extremely hot weather just after picking began, followed by weather in which there was much fog and dew at nighte “Like black mold rot, and evidently for the same reasons, the rot caused by Botrytis was most serious on Zinfandel. Examination of bunches of this variety in which the decay was only slight showed almost invariably that the decay had started in a cracked berry and had spread from that ‘to others around it. In a few instances it appeared that infection had proressed into the berries through the cap stem from an old lesion onthe min stem of the bunch. Such lesions may, of course, have resulted from growth of the fungus in- ‘ward to the min stem rrom infected berries; on the other hand they may have resulted from the spring infection reported by Milbrath. This seems to have affected only the blossoms and young grapes though there is a possibility that here and there the fungus spread into the main stem, but soan became dormant and remained so until favorable conditions later in the season caused it to resume growth. "In the Alicante Bouschet variety infection was usually worse in the tighter bunches. In the Tokay variety:it was confined almost entirely to bunches which showed the cracking described elsewhere in this papere In the Chenez variety in one vineyard it was found attacking the stem and occasionally the derries at the lower end of the bunch. Where only the sten was affected the berries attached beyond the stem lesion Were slightly browned and much shriveled." (D. H. Rose and W. S. Ballard) FROST INJURY In 1926 frost injury, confined largely to the old canes, caused consider- able loss in the Lake Erie region of New York. In Delaware only weakmed vines were affected but the commercial crop was not reduced in yield. Michigan re- ported a loss of 5 per cent. In Minnesota the loss was estimated at 0-5 per cent the crop being reduced by frost in only a few isolated places. Iowa reports the injury to be much more than the average year, due to a combination of a wet fall and an early freeze which killed mny vines. The loss in Arizona was estimated as a trace. ; 77 OTHER DISEASES AND INJURIES Bacterium tumefaciens EFS. & Towns., crown gall. Indiana and Utah. In egon, Barss reports crowm gallon European grape due presumably to Bacterium efaciens. He states that Muscats were resistant and Riesslings susceptible in asco County. The disease was common also in Josephine County. Clitocybe monadelpha (Morg. ) Sacé., root rot. Reports were received from outh Carolina and from Missouri. However, the fungus was not fruiting in either e, the determination being made solely on the nature of the mycelium and the ymptoms. In Missouri, where the damage was reported as slight, the grape root m Seems to be associated with the disease. Plants in low, moist ground have m holes and are covered with mycelium. These plants die but those on high dry und, Similarly attacked by the worm, are not affected with mycelium and do not Cryptosporella viticola (Reddick) Shear, dead arm. A single case was re- ted from New York. Glomerella cingulata (Stone) Spauld., ripe rot. Caused slight loss in ithern Missouri. In Arkansas, according to Rosen, a species of Pestalozzia is ociated with the ripe rot fungus. He states: "Much shelling of Concord grapes ether with a browmish discoloration of fruit stalks and a rotting of the fruit occurred in vineyards where ripening of fruit has been retarded. Acervuli of m Gloeosporium and Pestalozzia have been found on fruit and fruit stalks. The ptoms of the disease aré markédly differmt from those described in the lit- ture." Caconema radicicola (Greef) Cobb, root knot. California, 0.5 per cent loss. Ozonium omnivorum Shear, root rot. Texas, 5.per cent and Arizona @ per cent Phakopsora vitis ‘(Thuem. ) Syd., rust. In Florida, according to Rhoads, s disease often becomes abundant late in the season but it occurs so late that does not have economic importance. Sphaceloma ampelinum D By., anthracnose. Maryland, Ohio, Wisconsin, innes ota, and South Carolina. In none of these states was it said to be of im- Portance. i Chlorosis due to excess of lime. Texas, 0.5 per cent. & Pedicel canker (undet.)° This ‘trouble is rather important in Missouri and evidently it is not reported in the literature. In Jackson County, where it has Seen observed for a number of years, it caused a loss of 25 per cent in one imeyard of White Diamond. The disease was reported on the same variety from two other Widely separated localities. Later it was found in Wright County in the Miss ouri Fruit Experiment Station vineyards where it occurred on Niagara, Lady Washington, Janesville (all white varieties) and on Vergeens (a red variety). The Sease is prevalent before ripening of the fruit. The first symptom appears as : small area at some point on a fruit pedicel. ‘The area increases in size until € pedicel is girdled by dead tissue. The grapes below the girdle then become Ariveled end fall off. No organisms could be isolated and it seems probable that l@ disease is non-parasitic. (Archer) ? Uneven ripening (undet.) In Arkansas, Been states that vineyards in two counties Showed an unusual amount of green underdeveloped fruit in clusters of ripe fruit. In some instances this seemed to.be associated with a withering of Peduncles. Extreme dry weather alternating with rains is offered as an expla- eo of the trouble. 78 Grepe - Other Diseases m4 Recent literature le ass Wy ° NG@:2 10. alesis 12. Bennett, C. W.: Dead am disease of grape. _ Ann. Rep. Michigan. Hort. Soc. -5A: 22-24.., 1925. (wot BE Dest Bab! Bonnet, L, 0. A promising rancay for black measles. California Sta. Cire. 303: 1-10. 1926. Carne, W. M. Black spot or anthracnose of the grape vine (Gloesporium ampelophagum). Jour. Dept. Agr. West Australia. II,.3: 178-182. June 1926. Faes, H., and M. Staehelin. Le rougeot ou rougeau. Annuaire Agric. de la Suisse 27 (1): 109-121. 1926. and P. Tunduz. Station federale d’éssais viticoles a - Lausanne et Domaine de Pully- Rapport Annuel, 1925. Annuaire Agric. de la Suisse 27 (2): 241-270. 1926 «° Foex, H.,-and A. Ayoutantis. - D'une production rouge a con— ‘sistance gélatineuse que revet parfois la vigne au printemps. Bul. Soc. Mycol. France 40: 316-341. Apr. 1926. Gard, M. Le traitement de l'apoplexie de la vigne. Rev. Vitic. 64: 84-65. 1926. . 2 Hoc, Pe Le remplacement des manquants dans les vignes atteintes d'apoplexie. Jour. Agr. Prat. nes. 45: A76-A78. June 1926. Nougaret, Ree Folletage and apoplexy of the grape. California Cult. 66: 649. June,1926. Quaintance, A. L-, and C. Le Shear. Insect and fungous @memies of the, grape. U.S. Dept. Agr. Farm. Bul. 1220: 1-5A. Mar. 1926. Rhoads, A. S. Diseases of grapes in Florida. Florida Agr. Lxpe Stas Bulls 178: 75-156. Jan. 1926. Viala, P. Geographie de l'esca. Rev. Vitic. 65; 69-92. 1926. Lesions de l'esca. Rev. Vitic. 65: 105-121; 121-125; 205-212. 1926. _ Recherches sur les maladies de la vigne. Esca. Ann. Dpiph. di: dedoe dozer 201-208. Traitements de l'escas Rev. Vitic. 64: 1926. SL A BR RY LEAF SPOT CAUSED BY MYCOSPHABRELLA FRAGARTAE (TUL.) LIND. The common leaf spot was evidently of slight importance in 1926 judging from reports received from 22 scattered states. Losses reported were 1 per cent in Texas and a trace in Illinois. In eastern Virginia severe late infections Sceurrcad. In Michigen, according to F. C- Strong of the State Agricultural College, Dunlap is considered susceptible, while Premier seems to be more re- Sistant. In Oregon, Zeller states that Marshall, Orcgon, Wilson, and particularly Ettersburg No. 121 are susceptible. LEAF SUORCH CAUSED BY DIPLOCARPON BARLIANA (HLL. & EV.) WOLF i Leaf scorch was reported in 1926 from Connecticut, North Carolina, Vir- Zinia, Maryland, Delaware, and Arkansas. The disease was not considered to be important except, perhaps, in North Caroline where it wes found to the extent of 7) per cent on the calyces in some fields of Klondike causing the so-called "dead. Caps-" The trouble was found rather abundantly on Heflin's Early varicty in Virginia and on Gandy in Maryland. Rosen states that the discase was severe in frkensas on the variety known as "Texas", while Aroma grown alongside appeared to be almost immune. Wolf (1) notes the wide difference in susceptibility of var- ieties to the disease and suggests the planting of ‘immune or resistant varietics end spraying with Bordeaux mixture as control measures. Recent literature de Wolf, F. Ae leaf scorch disease of strawberries. North Gero ine Stas Toch. Bul. 20; 1-162°' 19208" POWDERY MIIDE] CAUSED BY SPHABROTHECA HUMULI DC. Powdery mildew was reported in 1926 from New York, Maryland, Delaware, New Jerscy, and Washington. Hcald and Dena (1) state thet an unusual deve lop— Ment of the discase occurred especially on Champion od Progressive varie tics in Spokane Valley in \ashington. The first crop was a complete loss in some CaScse Recent litorature ieeeicaid, Fo Ds, ond 8. F. Dana. 36th Ann. Repts’ Washington Agr. Exp. Sta. 1925-1926 (Bul. 208): 45. Nov. 1926. 8 v0 Strawberry MISCELLANEOUS DISEASES AND INJURIGS Botrytis sp», fruit rot. Reported from Connecticit, Mcrylenad, Delawarc, Virginir, No: North Carolina, and Cealifomin. «aA. G. Plakidas romarks that ordi-— Naxely tthe Strayberry fruic, rots, anc of slight importenée in California, but that this year, due to heavy rains in April ond May, about one-half of the first crop was ruincd. Collctotrichum sp., anthracnosc. Found in Florida by a. N. Brooks. In—- fected patches occurred in scattered localitics on Missionary varicty. The discase was noticed mainly on the mnners and very scldom on other parts of the plants. Young tissuc is attackcd re ome Dendrophoma obscurans (BLL. & Eve) And., angular spot. Florida, Wrsseunee and Illinois. sxccptionally severc. (Anderson) Fuligo sp. and other slime molds. In suveral cases growers stated that plants had been smothered by the slime mold. (White) Fusarium sp-, root rot. Moderately important in Massac and Florida. In all three states a Fusarium has been isolated tissue. 4S yet there has been no demonstration that this fungu the discasec. a dp) 99 Rhizoctonia sp-, black root rot. Reported from Kansas and Washington In Kansas, White states that often cntire patehcs are killed prcsumaoly by this dis cases. Black root is. reported to occur in Missouri-and Micnigen also, but in ny these swo states the cause is undctermined. In Michigan, aieene S GO te: Ore Strong, the disease was present in mny places where losses varica Trom 10 to 25 per cent. Rhizopus nigricans Ehr., leak. A 2 per cont loss was said to have occur— red in the ficld in eastern,and.southom Texas. One report was .rcecived 4n Connecticut. Tylenchus dipsaci ( Kuchn) Bast., stem nomatode. hicKeay in Oregon reports that the geoce se is known mostly along the coast and that it is spreading from ack to cultivated ones. is (CundcteJMnWexasis Mosaic (undct.)’ a trouble reported as mosaic occurred in Ohio, Indiana, and Wisconsin, and in Manitoba. Onio - The discase vhich is being deseribed in Ohio as the mosaic is showing =p and is quite prevalent, causing & distinct loss throughout our ORaDenEY section. -H. C. Young,.July 1). Manitoba paece found first time in 1925.) Aiso a little this year. (Bisby) Root burn Caiks 14) Fen Ss southern Texas. 4 cattcred traces in irrigated sections of Yellows (undet.) Colorado. This trouble has beon reported from several locations in the state, but not at all: severe. (Learn). Cslifomia — Gontinu to De.scrious throughout central corstal districts of Califommia. Sprcads rapidly through new ficlds of Banner, Marshall, and Oregon varictics and caused permancnt stunting. Other varictics are affectcd but in varying dcgrces. (Horne). Etter®s selections very resistant; Marshall, Bammer, Oregon very susceptible. (Plskides)s Yellows, as it oceurs on the Pacifie Coast, is apparontly a virus "desteses aes Gerding to Plskidas, (2). et (cs Reecnt litcrature 1. Hodson, W. G. Notes on the stem celworme Jour. Min. Agr. Great Britnin 33: 259-262. June 1926. § 81 strawberry — Discases ond Injurics Raspberry — janthracnosc Pe Plokiudas, de Ge strawberry ‘yellows ina dogenern ti on di scase of the strawberry. Phytopath. 16: 423-426. 1926. 40 Rosic,. Dean. H. | Discases of strawberries on tho markot, U.S. Vepus cher. Cire. 02: 128, Dec. 1926. A. Rolation of strawberry fruit rots = weather conditions in the ficld. Phytope th. 16: 229-232. 1926. 5. Stanilend, L. N. Some obsurvations on strawberry cclworm. Ann. Ropte Agr. & Hort. Ros. Sta. Univ. Bristol 1925: 61-65. 1926. er ee ANTHRACNOSE CAUSED BY PLsCTODISCHLLA VENETA (SPEG.) BURKH. In 1926 anthracnose was reported rather general] ly. ag OLES sn ca most of the territory east of the Great Plains THEI ie The losses for 1926 are given in table 24. Pennsylvania: ‘this is by far the worst fungous disease of raspberries in the state. It is easily controlled by lime sulfur spray. (Krout) Virginia: Most important raspberry disease of state. (Schne iderhan) Arkansas: The limiting factor in raspberry culture. (Dept. Pl. Path.) ete Wisconsin: Severe enough to note in 16 nurseries. (Vaughan) Towa: Drought in early season checked disease. (Gilman) Oregon: Our dry summers must keep the disease in check. (Zeller) It is generally recognized that red varieties of raspberry are rather re= Sistant to anthracnose while black varieties are susceptible. This fact was fur-— Wher attested in 1926 by reports of collaborators. Bennett in Michigan and Archer in Missouri report red varicties to be resistant. In Missouri the red raspberry does not propagate freely and is subject to winter killing and therefore is not grown commercially. Black varicties were reported to be susceptible in Minnesota, New York, Oregon, and Missouri. Table 25 represents data on varictal susccpti- bility which has been compiled from the literature and from reports of collabor-— ators. It Will be seen that there is a lack of agreement regarding the resistance Several varicties. §2 Raspberry — Anthracnose Table 24. Percentage losses from raspberry anthracnose, as estimated by collaborators, 1926. Percentage: +:Percentage: loss :States reporting loss :States roporting 10 : Ponnsylvania Bs 1 : Minnesota, Towa i 2 Virgina “$3 2 : Miichigan : Maryland, Indiana es i : Ohio, North Dakota 5) : Kansas oe op Mew - Yorks Table 25. Data on varictal susceptibility to anthracnose compiled from literature and from collaborators' reports. Resistant Susccpt ible Very Resistant Columbian (P) (1)* : Columbian(P) (6)* : Antwerp (R) (14) Hoosier (B) (15) 2 Cumberland (B) (14) ; Cardinel (P) (10) Quillen (B) (12) : Cuthbert (R) (11,14): Columbian(P) (11)* Van Flcet (R) (13) Kansas: (B) (ad) : Cunher smd (BY loan 7 - - 10 s Kine (RP (2,9) : Eureka (B) (14) : Latham (R) (2) : Gregg (B) (3,5,7,14) : Miller (R) (9) : Kensas (B) (8,10) : Plum Farmer (2) (13 : Mammoth Cluster (B) (14) hy 14) : : : Ohta (R) (2 : Plum Parmer (B) (1,3,4) Sunbeam (R) (2) : : Turner (R) (9) (Pp) - Purple varicty. (B) — Black varicty. (R) -— Red variety *The Columbian, according to Burkholder (11, p. 158), "forme rly was regarded as nearly immune, ‘but it now exhibits « marked suscepti- bility. It is not known whether this vericty really possessed re- sistance at one time or whether merely the stock was free from the discasc." References and cuthoritics for date on varictal susceptibility. (1) Reported in 1926 to the Plant Disease Survey by W. S. Krout from Ponns ylvania. (2) Revorted in 1926 to the Plant Discase Survey by the Section of Plant Pathology of Minnesota. (3) Reported in 1926 to the Plant Discase Survey by C. W. Bennett from Michigan. (4) Reported in 1925 to the Plant Dis vase > Survey by G. P. Clinton from Connecticut. 83 Raspberry - Anthracnose; Leaf Curl, Mosaic (5) Reported in 1924 to the Plant Disease Survey by W. S. Krout and C. R. Orton from Pemsylvania. (6) Reported in 1923 to the Plant Disease Survey by E..F. Guba from New York. AE: f ut (7) Reported in 1923 to the Plant Disease Survey by J. F. Adams from Delaware. (8) Reported in 1921 to the Plant Disease Survey by J. A. Blliott from Arkansas. ; (9) Reported in. 1919 to the Plant Disease Survey by R. E. Vaughan from Wisconsin. yt (10) Reported in 1919 to the Plant Dis ease Survey by W. E. Maneval from Missouri. (11) Burkholder, W. R- in Comell Agr. ee Sbasubull. Soul 17 < (12) Colby, A- S. in Amer. Fruit Grower Mag. 46 (3): 50. 1926. (16) Marrow, G. Mo im UcS-D.A. Circ. 320. 1924. (14a) Gregory, ©. T. in Hoosier Hort. % (4)2 35-39. 1925. (14) Rhoads, A- Ss in Ozark Fruit Grower 9: 3-5. 1924. (15) Taylor, W. A. in U.S.D.A. Yearbook 1910: 429-430. 1911. Recent literature 1. Ulrich, F. Spraying raspberries. Minnesota Horticulturist 54: HF B08 V T9265 Aig LHAF CURL, MOSAIC, AND STREAK (VIRUS) Leaf curl . Leaf curl in 1926 was reported*from Connecticut, New York, Pennsylvania, /Maryland, Ohio, Illinois, Indiana, Michigan, Minnesota, Iowa, North Dakota, _ Nebraska, and Washington. Estimates ef losses were given by collaborators as Meeollows: Ohio, 3 per cent; Pennsylvania, 5 per cent; Maryland and Michigan, 4 Meper cent; North Dakota, 2 per cent; and Towa, a trace. ' In Pennsylvania the disease is easily controlled by roguing (Krout). > The report from Nebraska is the first for that state (Goss). In Minnesota an un- _ usual condition occurred in a few scattered plantings where 75 to 80 per Cent on leaf curl appeared svddenly after several years of apparent freedom from the _ disease (Sect. Pl. Path.). In New York a large amount of the disease was found _ on stock impor ted from Canada and Michigan (Mills). With reference to varietal susceptibility the following notes were sub- MMitted by collaborators: In Minnesota, Latham and King resistant; Marlboro and Cuthbert susceptible. In Iowa, black varieties are susceptible. In Michigan, King and Plum Farmer are immune; Gregg and Viking and especially Cuthbert, Victory, anc Cumberland are susceptible. In Connecticut, Cuthbert is susceptible. Reported to be present in Connecticut, New York, New Jersey, Pennsylvania, Maryland, Virginia, North Carolina, Ohio, Michigan, Wisconsin, Minnesota, Iowa, Kansas, Colorado, Washington, ard Idaho. The estimated losses for 1926 are given in table 26. Raspberry — Mosaic Pennsylvania: The disease is being controlled by a thorough system of roguing which has been practiced for four consecutive years. By the spring of 1927, 400,000 disease-free plants will be ready for distrivoution. (Krout) Wisconsin: Nearly half of nursery stock was refused certi- fication because of mosaic. Seven types of the disease are recog— niized in inspection. (Chambers & Vaughan) Minnesota: Mosaic and mildew are so closely associated that it is not possible to estimte the relative amount of damage caused by each. (Sect. Pl. Path.) Kansas:. First discovery in the state. Found on Latham variety introduced from Minnesota. (White) Idaho: Most serious ras berry disease in state. (Hungerford) Collaborators' reports for 1926 on varietal susceptibility are incon- Sistent in certain points but they are listed as given: Connecticut: Herbert very resistant; King, Golden Queen, and Cuthbert susceptible. Reports received; several serious. Mostly on red varieties but some reports received of slight injury on black varieties, i-ee- Plum Farmer and Cumberland. (Clinton & Hunt) New York: Herbert and Latham resistant. | Michigan: All varieties suceptible. (Bennett) Pennsylvania: -Ali varieties susceptible. (Krout) Indiana: Black TeeEeeR ghbepots bie (Gardner) Minnesota: Sunbeam and St. Regis apparently resistant. tham very. susceptible to infection but very tolermt. King nd Marlboro iess susceptible to infection and less tolerant. ect. ees Path.) fy Iowa:- Jne hundred per cent infection found on Columbian. Table 26. Percentage losses from raspberry mosaic as estimated by collaborators, 1926. Percentage: ::Percentege: loss :Otates reporting ois ioss States reporting 40 : Pennsylvania 2 4 : Maryland 15 : New York Eis 2 : Connecticut, 1A : Minnesota - : Rien 2 i? : Michigan :: Trace : Virginia, Iowa, S : Ohio Sc E eee 85 Raspberry -— Streak; Blue Stem Streak J No reports received from collaborators in 1926. The disease is discussed by Berkeley and Jackson (1). Recent literature 1. Berkeley, G. H., and A. B. Jackson. Studies in raspberry diseases. Mosaic, leaf curl, rosette, and wilt. Pamph. Canada Dept. Agr. n.s. 72: 3-15. 1926. eye Glent, P. Ae The mosaic situation in Tliinois. Proc. Wisconsin State Hort. Soc. 56: 117-121. Aug. 1926. ‘43. Hanchett. Raspberry mosaic. Proc. Wisconsin State Hort. Soc. 56: A0-AA. Aug. 1926. A. Rankin, W. H. Raspberry mosaic control in Hudson River Valley. Proc. New York State Hort. Soc. 71: 173-178. 1926. 5 Mosaic of red and black cultivated raspberries. (Abstract) Phytopath. 17: 46. Jan. 1927. 6. Ruggles, A- G., and J. D. Winter. Some aspects of mosaic of the red raspberry from the standpoint of the nursery inspector. Minnesota Hort. 54: 7985. Mar. 1926. 7+ ‘Thatcher, R. W. Forty—fourth Ann. Rept. New York Agr. Exp. Sta. 1924: 29. 1926. Be Winter, J. D. Raspberry mosaic in Minnesota. Proc. Wisconsin State Hort. Soc. 56: 121-130. Aug. 1926. BLUE STEM (WILT) CAUSED BY VERTICILLIUM ALBO-ATRUM REINKE & BERTH. Blue stem in 1926 was reported in scattered localities in New York where, according to Mills, 10 per cent infection occurred in some fields. It was said to be increasing in Erie and Monroe Counties. In New Jersey, the Department of Plant Pathology reports that the disease was first recorded July 14 at Richfield in Passaic County. In California, according to B. A. Rudolph: "The disease occurred locally in the San Francisco Bay region. The variety Syracuse was resistant but Columbian Purple, Cuthbert, Ranaree, and black cavs were susceptible, especially the last two named. One field of Ranaree showed 40 per cent of the plants infected. The first infection was noted in June near Palo Alto. In general the season was not favorable in this district for the development of the disease." 86 a Raspberry — Blue Stem; Winter Injury; Other Diseases Recent literature 1. Berkeley, G. H-, and A. B. Jackson. Verticillium wilt of the red raspberry. Scient. Agr. 6: 261-270. Apr. 1926. 2. Harris, R. V. The blue stripe wilt of the raspberryes Ann. Rept. East Malling Res. Sta. 1924: 126-134. 1925. WINTER INJURY In 1926 frost injury was reported from New York, Pennsylvania, Michigan, Minnesota, Iowa, Missouri, South Dakota, and Oregon. Reports of losses were: Minnesota, 55 per cent; Iowa, 15 per cent; Pennsylvania,.1 per cent; and Michigan, a trace. New York: The injury occurred in Erie and Wayne Countics. Especially on red varieties. (Mills) Michigan: Cuthbert and Cumberland were susceptible. (Bennett) Minnesota: In 1926 there was much more damage than in the average year, in some plan tings 100 per cent of the plants being affected. Wet weather in fall of 1925 following long dry period caused plants to continue growing lete into the winter. Sunbeam and Ohta were very resistant; Latham moderately resistant and King was susceptible. (Sect. Pl. Path.) : i) Iowas «Wet fell and early freeze ceused great deal of injury. (Gilman) . : Missouri: Red varieties are especially susceptible. (Archer) Oregon: This year there was a type of injury affecting 25 per cent of canes in the worst places. We suspect that this was due to late growth of canes in 1925, thus partially using the reserve which was needed the following summer (in 1926). (Zeller) Recent literature 1. br rank, A. Winter injuries to berry plants. West. Fruit. 8 (2): Il, 1W2Tbeo Febt 19268 OTHER DISEASS=S Ascospora rubi (Westend.) Zeller, cane spot. This is the most common cane- ae é : : inhabiting fungus of most brambles in western Oregon and Washington and in average years I believe it must do more damage than spur blight. (Zeller (4) 87 Raspberry -— Other Dis cascs Bacterium tumefacicns EFS. & Towns., crow gall. Reported in 1926 from New York, Pennsylvania, Maryland, Virginia, Tennessee, Ohio, Indiana, Michigan, Wisconsin, Minnesota, Iowa, Nebraska, Kansas, and Idaho. The losses were esti- mated as 6 pen Cens imiMechigsan and Lows): Sper cent )in, Ohio and.Kansas: 2 ‘per Sent in Pemsylvania and Minnesota;.1 per cent in Tennessee; and a trace in New York, Maryland, and Virginia. In Wisconsin plants pulled in roguing for mosaic showed 15 per cent infection with crow gall (Vaughan). In Pennsylvania the in- fection Was said to.bc heavicr.in light sandy soils. A great deal of rain in lattcr half of yéar seemed to cause a rapid growth of galls (Krout). In Tennessec the St. Regis variety was very susccpt ible (McClintock). In Michigen, King, Cumberland, Plum Farmer, Cuthbert, end Columbian were susceptible, especially the ast two named (Bennett). In Oregon, Barss reports one doubtful case of crown gall on canes of black caps. Gymnoconia interstiticlis (Schl.) Lagh., orange rust. Reported from New York, Illinois, Towa, and Washington. Orange rust was unusually severe in New York on black raspberries, especially the Orlando. In TFllinois the disease was rare. In Iowa it occurred moderstcly in the southwesterm pert of the state. Germination tests in Washington proved the long cycle form to be present. Leptosphacria coniothyrium (ickl.) Sace., canc blight. Reported from Vir-— Ginia, Missouri, and Oregon. In Oregon, according to Zcller, the fungus caused damage for the first time. It was found on the Munger varicty which had been at- tacked by the strawberry root borers The fungus entered through pruning wounds oid kidided some of the. laterals. Mycosphacrella rubi Roark, leaf spot. Now York «nd Missouri. Mycosphacrella ruvina (Pk.) Jacz., spur blight. Indiana and Oregon. In wendiana the fungus;occurred on the Cuthbert varicty as a leaf spot, according to Gardner. Zeller states that damage oceurs only in the Ashland district of south- yern Oregon, although the fungus is widespread in the Willamette Valley. Pezizella lythri (Desm.) Shoar & Dodge. Observed in one locality in Missouri on living canes. Phragmidium imitans Arth., leaf rust. Washington and Oregon. In Oregon, meccording to Zeller, it occurred on the Cuthbert varicty in the Willamette Valley. He stetes that the lesions on the canes are usually destructive but that they werc “mot common in 1926. Pucciniastrum americanum (Farl.) Arth., rust. Roported on Rubus idaeus | Aaculeatissimus in Wisconsin. : Sphacrothces humuli (DC.) Wint., powdery mildew. Reported for second time trom Connecticut where Stoldard states that the Letham varicty was attacked but That Cuthbert ncarby was not effected. In Minnesota mildow is closcly associated With mosaic. | Recent literature 1. Colby, Ae S., and H. W. Anderson. Diseases of brambles in Illinois and their control. Illinois Sta. Circ. 405: Ha20s, »! 19266 e~ Dodge, B. 0O., and R. B. Wilcox. Diseases of raspberries end Blackberries. U. S. Dept. Agr. Farm. Bul. 1488 : 1-42. June 1920. 88 Raspberry —,Other Diseases Blackberry - Orange Rust; Anthracnose Be Harriers Vie Three rasp berry dis cases. The blue stripe wilt, cane spot discase, mosaic. Fruit Grow. Fruite, Flor. & Mark. Gard. 62: 205-206, 208. Aug. 12, 1926. 4. @Zclicr, 8. M. A correction. Mycologia 19: 150-151. May-June 1927. Goryncum mborum Oud. = Hondersonia rubi (West.) Sacc. as suggested by Archer. Ascospore stage should be called Ascospora mbi (estend.) Zeller instead of Ascospora ‘ryuborum (Oud.) Zeller. BUT Con BIE VROROS ORANGE RUST CAUSED BY GYMNOCONIA INTERSTITIALIS (SCHL..) LAGH. AND KUNKELIA NITENS (SCHW.) ARTH. These two rusts, not always easily separated, were reported widespread in the United States. The losses as a rule are very slight and in 19 26 only six states gave estimates; i.e., Michigan, 4 per cent; Pennsylvania, O.1 per cent; “Maryland, Iowa, Missouri, and Kansas, a trace. In Michigan, according to Bennett, Eldorado is quite resistant while Kittatinny and Blower are susceptible. In Tennessee, McClintock states that Harly Harvest is susceptible. Recent literature 1. Dodge, B. O., and Ll. O. Gaiser. The question of nuclear fusions in the blackberry rust, Caeoma nits:s.. Jour. Agr. Rese 42: 10045-1024.. 1926. ANTHRACNOSH CAUSED BY PLECTODISCELLA VENETA (SPEG.) BURKE. Anthracnose was reported in 1926 from New York, Delaware, North Carolina, Arkansas, Minnesota, Missouri, and Oregon but evidently it was of slight impor- tance as only traces of it were said to occur. In Delaware the disease was gen- erally observed in home plantings (Adams). In New York it was thought to be im- portant only in Chautauqua County (Mills). In Missouri most of the plantings are conducted on a scientific basis with proper spraying, pruning, etc., thus re- ducing losses to a minimum (Archer). In Oregon the disease is not a factor due perhaps to the dry summers (Zeller). Blackberry to Dewberry 89 OTHER DIS TASES Bacterium tumefaciens HFS. & Towns., crown gall. Texas, Idaho, Washington, and Oregon. In Porto Rico, Cook reports one case was found at the Experiment Beation On a plant sent from the United States. Ceregspora rubi’Sacc., blotch. Caused a 15 per cent loss in North Carolina according to Poole. Blotch caused heavy defoliation of plants during “the late season when the new canes were being formed. Leaf infection was 100 per cent in ) every field and the coalescing of spots was so heavy that many leaves were shed. Fusisporium mbi Wint., reported as double blossom. Common in Louisiana. * x i % e(Tims) Mycosphacrella rubi Roark, leaf spot. Occurred in New Jersey, North Caro- Setoa, Indiana, Texas, and Missouri. ‘The losses were estimeted as 0.5 per cent in Blexes and as a trace in Missouri. In North Crrolina, Poole reports much injury Bto the canes because the fungus remained active in spots near the ends of the " eanes throughout the winter. In some fields the girdling of the canes just before the berries ripened caused heavy losses ; Frost injury. Reported from North Carolina, Minnesota, Iowa, and South Dakota. In North Carolina, Poole stated that the injury resulted in poorly formed Merrics- In Minnesota the lack of wintcr hardiness is the limiting factor in the “Culture of blackberry. ecent literature 1. Weber, G. &. Double blossom of blackberry. Citrus Indust. 7 C2). -Gas Peps 4926. Be ips) 4 1B pt = ol aad Cereospora rubi Sacc., blotch. Reported from North Carolina by Poole who femarks thet "On such perennials as the Llucrctia cdewberry the disease caused se— meere defoliation in’some fields carly in September. The normal growing season Extends into December end the defoliation will probably result in a shortage for Weems 1927 crop, since the cance growth in badly hee ed fields is not well devel- Moped. The discase was prevalent in cvery dewberry field examined." Gymnoconia interstitialis (Schl.) Lagh., orange rust. New York, Arkansas. Mycosphacrella nibi “Roark, leaf spot. Tcxas- Plectodiscella venota (a) Burkh., anthracnose. In North Carolina there as only a slight infection . in the VaoP ne hy of Cameron, where the disease caused heavy losses in 1925 (Poole). One report from Missouri. | Mosaic (virus). In Washington, mosaic was the cause of considerable damage. Frost injury. In North Carolina, Poole reports that the lucretia variety “as affected, with poorly formed berries as a result. Bie cant literature its control. North Carolina Agr. Exp. Sta. Bul. 240: i ; ig 1. Wolf, F. A.-, and B. O. Dodge. Anthracnose of dewberries and ils. eb. 1926. = \ Loganberry to Gooseberry LOGANEBARRY ‘from Oregon. Zeller - He mentions that the little damage that Mycosphaerella mbi Roark., lear spot. Reporte States that the disease is important also as a cane sp disease is serious in some years but usually it does s frowers, cannot. be induced to spray for it. Plectodiscella veneta (Speg.) Burkh., amchracnose. Reported from one locality in Washington. ' Verticillium seis Reinke & Berth., blue stem. In Califomia Rudolph states that red and black varieties of loganberry are very resistant to bDlue stem. DWart. This ee e, evidently due to a virus, was reported from Oregon by Zeller. A small planting of about one-half an acre was observed in which about 15 per cent of the plants were diseased. Coit sdttodnwN ude Botryosphacria ribis Gross. & Dug., cane blight. Reported from New Jersey. | Pseudopeziza ribis Kicb., anthracnose. Indiana. | Puccinia grossulariae (Schum.) Lagh., rust. Severe in some parts of North Dakota (Brentzel). Recent Tite rau re 1. Briton-Jones, H- R- A note on the leaf spot disease of black currants (Pseudope 2zZi za ribis). anne Rep. Agr. & Horte Res. Stat. Univ. Bristol 1925: 105-108. 1926. 2. Cobb, A. Je Reversion or nettle nead in black currants. Garden 90: 325. June 5, 1926. 4. Stevens, N. lh. Occurreme of the current cane blight fungus on numerous. hosts in the Southern States. iycolvgia 18: 278 202. 1926s ibek a Botrytis cinerea Auct.-, dic-back.e Reported on Oregon Champion from one locality in Oregon (Barss). Pseudopeziza ribis Klcb., anthracnose. In Illinois anthracnose was very abundant in all sections of the state and caused defoliation early in the season (Anderson). The disease was reported also from New Jersey where it caused mod- erate damage. In western en the disease is general and Serious when not controlled with Bordeaux mixture (Barss). Puccinia grossulariac (Schum.) Lagh., rust. Severe in some parts of North Dakota. ety i iL Gooseberry t9 Cranserra 3 Scptowig grossuliw age Missourie Sphaerotheca mors—uvae (Schw.) Berk. & Curt., powdery mildcw.* Uonnecticut and Oregone ‘ Igete SOs SLL tly, ip Oretcata un pa Recent literature 1. Anon- The dic-back disease of gooscberry (Botrytis cinorea Pors-) Gard. Ghron. TIT, 80: 434. Nov. 27, 1926. 2. Anon. Gooscberry rust. Scottish Jour. Agr. 9: 308. July 1926. CRANBERRY In 19 26 the Division of Plant Pathology of the Washington Agricultural Experiment Station reported the following crenberry disuases to be present in Washington. The m jority of the fungi were found oniy in Pecific County. Exoba- sidium oxycocei Rostr. (hypertrophy) slight importance; Exobasidium vaccinii (Fekl.) Wor. (red leaf spot) very important; Fusicoccum putrefacions Shuar (end rot) very important; Glomerella cingulata vaceinii Shcar (bitter rot) slight im- portance; Guignardia vaccinii Shear (blast) slight importance; Pestalozzia sp. (rot) slight importance; Venturia compacte Pk. (1lucf smudge) slight impor tance; Sclerotinia oxycocei Wor. (hard rot) very important. Sclerotinia oxycocci was also reported from Wisconsin by H. F. Bain of the State Department of Agriculture. He estimates the loss to be a trace for the State With a 4O per cent infection found in some ficlds. The disease was most Severe in Juneau, Monroe, ad Jackson Counties. He mentions that dry weather Conditions wore unfavorable for the development of the fungus, since it is con- Sidered that rainy weather is necessary during the time cf discharge of ascospores and conidia. The tip blight stage appears at about blossom time. Berry infection occurs during or just after blossoming while the typical hard rot stage is reached at harvesting time. With relation to storage rots in Wisconsin, Bain. has reported that: "The harvesting season was the most unfavorable on record. It was very rainy and there were some freezes, both conditions being conducive to rot. It is impossible to estimate loss since most berries were remilled as often as required and eventually sold. Real loss consisted of remilling charges and low prices at which unsound fruit had to be sold. Poor keeping quality aided abnormally large production in depressing market value of the crap. On the basis of incomplete culture studics, the active fungi were: Fusicoccum putrefaciens (end rot) most prevalent rot; Guignardia vaceinii (carly rot) some; Acanthorhyncus vaccinii (rot) slight; Phomopsis sp., slight; Penicillium sp. (ripe rot) slight; Ceouthospora lunate (black rot) very Slight; Helminthos- p2rium inaequalis Shenr, trace. "Most of the trouble was experienced with Searl's variety 92 diseases in Massacnuss Recent Cranberry to Blueberry and least with Howes (very small production), McFarlins and some native varictics. All other varieties were intermediate between these with no extensive trouble in the production of any of then. The crop as a whole kept poorly md, in addition to the varietal difference noted ce some dogs suffered more ee others with— out relation to geographical location or variety.' The following report submitted by Neil f&. S1S EU = deals with cranberry tts and is W SS "The most serious disease of cranberry plants at the present time is false blossom, formerly called Wisconsin false blossom, the cause of which has not yet been determined. It is apparently on the increase in both Massachusetts and New Jersey, although it is impossible to tell with any degree of accuracy how much of the apparent increase is due to increasing interest in the disease and to the fact that many growers are now able to recognize it in their bogs. "The amount of loss, from fruit rots in New Jersey was not very different from that of the last ‘two years’ That is) if was somewhat above the average for that state. "In Massachusetts, the Early Blacks, which constituted about haif the crop, showed cxcellent keeping quality but there was much loss from decay in the Howes (the chicf late berry). Part ofthis loss. may no doubt be attributed to the fact that this is the largest cranberry crop on record and some of the berrios were held much longer than usual. Comparative storage tests ¢ ut in Chicago on -ber- rics from Massachusetts and New Jersey as Wwoil as Cregon and Wisconsin showed end rot to be more important in storage than all other rot fungi combined." literature 1. Stevens, N. o-, and Wi. H. Sawyer. The distribution of cranberry false blossom. Phytopath. 16: 223-227. 1926. Ce he false blossom situation. Proc. Amer. Cran. Grow. Assoc. ee 20-26. 19275 The Department of Plant Pathology in New Jersey reports finding what appears to be a new Steen” of the blueberry. The diseased plants were found at Whites Bog in Burlington County. A gall-like formation resembling black knot covered the entire stems. Out of 1§ isolations, 15 colonies of a Fusariun were ovtained but this fungus is not beliewed to be the original cause of the galls. Do Cicrus) Pruaes ="Cenker MULBERRY Ozonium omnivorum Shear, root rot. Prevalent in the black lands of Texas, sausing a loss of 1 per cent, according to Ta benhaus. : oclerotinia carunculoides Siegler & Jenkins, popcorn disease. Reported Mirom Texas, Florida, Georgia, and South Carolina. A specimen received from Florida is the first collection in that state, according to Miss Jenkins. q 1. Nicolas, G. Un nouvel héte de Ganoderma applanatum (Pers. ) Bul. Soc. Mycol. France 42: 190-191. Nov. 15, 1926. q Prepared by H. Re Fulton q Ce BIR Si oe RU Ts I. “DESEASES CAUSED BY OR ADPRTBUTED TO PARASTTES CANKER CAUSED BY BACTURIUM CLTRI (HASSE) JEHLE In Florida two infected trees were found and destroyed at Sebring in cember, 1926. Tims reports the occurrence of citrus canker on orange at Hhibodaux, Louisiana. None was reported from Ale sama, Mississippi, or Texas. cent literature 1. Neal, D.C. Scouting for citrus canker. Quart. Bul. Mississippi State Pl. Bd, 6 (2): 14-15. July 1926; 2. Peltier, G. L., ad Ww. J. Frederich. Effects of weather | on world distribution and prevalence of citrus. canker 3 and citrus scab. Jour. Agr. Res. 32: 147-164. 1926. Further studies on -the overWintering of Pseudomones citri. Jour. Agr. Res. 32: 335-345- 1926. 94, Citrus Fruits BLAST AND BLACK PIT CAUSED BY BACTERIUM CITRIPUTHALE OC. O. SM. (B. CITRAREFACIENS L TT pushy Pawcett reports that black pit is of minor importance on lemon fruit in California, while blast occurs locally in the northern part of state on navel oranges. Lewcock (2) and Carne (1) report the occurrence or the organism in South Australia and in Western Australia, respectively. Recent literature 1. Carne, W. M. Citrus pit (Pseudomonas citriputeale, C. QO. Smith). Jour. Dept. Agr. West. Australie II, 3: 37 8- Boils Bepte L926 2. lewcock, H. K. A citrus bacteriosis occurring in South Australia. (Abstract) Phytopeth. 16: 80. Jan. -1926. 3. Smith, 0. O. Similarity of bacterial diseases of avocado, lilac, and citrus in California. Phytopath. 16: 235- 236. Mar. 1926. SCAB CAUSED BY SPHACELOMA FAWCETTI J@NKINS (SPOROTRICH UM CITRI BUTLER) Florida: Scab on grapefruit was gencre]1 od much more prevalent then usual. Cool rainy weather in late March Tavorea infection. Loss was duc to heavy drop of small fruit, and to the culling of seabby mture fruit. (Winston) Occurred on grapefruit and lemons in moderate amount in scattered localitics, being of considerable importance im the central ridge section. (Rhoads) Alabama; Satsuma oranges in Mobile and Baldwin Counties are very susceptible; satisfactorily controlled by spraying with Bordemux mixturee Unusually heavy infection on fall flush of growth. (Fulton) Louisisna: Reportca by Tims on Satsuine oranges. m i exas: Reported as unimportant by Toubecnhaus. Porto Rico: Much less severe than usual on fruit from winter bloom, more severe on later blooms. (Cook) op Citrus Fruits - Scab; Melanose _ Recent literature 1. Peltier, G. L., and W. J. Frederich. iiffects of weather on the world distri dition and prevalence of citrus canker and citrus scab. Jour. Agr. Res. 32: 147-164. 1926. 2. Winston, J. Re, Je J. Bowman, and W. J. Bach. Relative susceptibility of some rutaceous plants to attack by citrus scab fungus. Citrus Industr. 7 (43): 26-29. Mar. 1926. . MELANOSE CAUSED BY DIAPORTHE CITRI (FAWCETT) VIOLF (PHOMOPSIS co - CLTRI PAVICETT) Florida: Less prevalent than usual, but gereral in all old plantings; grapefruit most susceptible, oranges and tangerines less so; pruning out dead wood reduces infection of young fruit and leaves, but spraying with Bordeaux mixture is more effective. (Winston) More leaf infection of grapefruit, and less fruit infection than in previous year. (Kuntz) Alabama: Somewhat more prevale@t than previously, but of slight importance; the routine spraying of young fruit with Bordeaux mixture keeps melanose in check. (Fulton) Porto Rico: or pee good results from treating with Bordeaux spray. (Cook) } The melanose reported in 1925 (Pl. Dis. Neptr. Suppl. A7: 282. 1926) on _ teaves of sweet seedling orange from Arizona proved to be false melanose, not the _ true melanose caused by Phomopsis citri, which apparently does not occur in that Ves tate . th Wolf (3) reports tlhe discovery of the. perfect stage of Phomopsis citri, | Which he calls Diaporthe citri. Meecent literature 1. Fulton, H. R. Spraying for gitrus melanose control. Gibrus Indastr. 7 (4): 6-7, 51. Mar. ean a Spraying for control of cass nodeniouee Florida Grow. 33 (11): 6, 29. Mar. 13, 1926. Wolf, F. A. The perfect stage of the fungus which causes melanose of citrus. Jour. Agr. Res. 33: 621-625. Dotty. i, 1926. NI Ae Something new about melanose. Proc. Florida State Hort. Soc. 39 (192): 153-154. 1926. Citrus Fruits — Stem, End Rot; tine and Green liold Rots Tall END ROT CAUSED BY PHOMOPSIS CITRI FAWCSTT or DIPLODIA NATALENSIS EV. or OTHER FUNGI Rhoads reported Phomopsis citri on oranges and grapciruit in Florida. Both the Diplodia and See types are of slight importance on Satsuma oranges in Alatsma (Fulton). In Porto Rico, Phomopsis is of very little impor- tance, but Diplodia is severe in some places (Cook). In Califomia, Phomopsis ealifomica Fawc. causes.a minor rot of lemons only (Fawcett) . Stevens (1) reports that the perfect stage of Diplodia natale@isis is Physalospora rhodina (Berk. & Curt.) Cke-, which is also the perfect stage of Diplodia gossypina ypina and occurs on numrous other hosts. Two other species of Physalospora are reported by him as occurring on citrus, one found in Cuba, des— cribed by him as a new species, P. fusca; the other, P. malorum (Pk.) Shear & Stevens collected in Alabama by Fulton. Another similar fungus, a Botryosphacria Very Simijiar to Bs ribis Gross. & Dug-, was found in a culture isolated from a rotted orange from Califomia. Recent literature 1. Stevens, N. Ee Two species of Physalospora on citrus and other hosts. Mycologia 18: 202-207. Scpt.-Oct. 1926. BLUE MOLD AND GRUEH MOLD ROTS CAUSED 3Y PENICILLIUM ITALICUM WEHMER AND PENICILLIUM DIGITATUY (FR.) SACC. Florida: Slightly more severe than usual in January; can be controlled to some extent by borax treatment. (Fulton) Alabama: Caused slight losses on marketed fruit. (Fulton) Califomia: Penicillium digitatum very important; borax wash a help in control. Penicillium italicum more prevalent than usual, especially on lemons, not effectively controlled by borax treatnet. (Fawcett) Porto Rico: Of little importance: (Cook) Recent literature 1- Benton, R. J. Borax treatment of lemons for store. Agr. Gaz. New South Wales 38: 94. 1926. 2. Hostetler, V. V. Prevention of decay in citrus. fruits. Better Crops 7 (1): 14, 44, 50-51. Sept. 1926. Citrus fruits — Blue aie. Green Mald Rots; Fruit Rots 4. Powell, H. ©. ‘The control of blue and green molds of orange. Negative results from borax. South African Fruit Grow. 13: 232. Sept. 1926. Ae The use of ‘sodium borate for the control of blue and green molds of oranges. Pretoria, 1926. FRUIT ROTS CAUSED: BY VARIOUS ORGANISMS Alternaria Citri Pierce, black rot, occurred in the usual very slight amounts in Florida and Alabama (Fulton). It was observed in several groves in Arizona, causing premature ripening of the fruit (Arizona News Icttcr). It caused less damage than last year, about the normal amount, to navel oranges (Fawcett). Bartholomew (2) states that Alternaria causes probably more decay to Califomia lemons than any other one fungus, except possibly Fenicii lium: The following organisms were reported (by Fawcett exccpt where other- wise indicated) from California, mostly as of moderate or slight importance. Aspergillus niger Ticgh. Botrytis cincrea Pors. Oospora citri-aurantii C. 0. Sms, sour rot, less prevelmt than last year on lemons. Penicillium roseum Link, pink mold, a minor rot of Iumons. Pleospora sp. causes mainly a stor age rot of lemons that was observed only occasionally. 2,3 Pythiacystis citrophthora E. H. & 7 BE. Sm., brown rot, on fallen orange fruit. (Horne) Sclerotinia sclerotiorum (Lib.) Mass. Trichoderma lignorum (Todv) Harz, a minor rot of lemons. Recent literature 1. Bartholomew, E. T. -Alternaria rot of lemons. California Agr. Exp. Sta.’ Bule 408: 1-32.. Oct. 1926. as . Conecrning Alternaria rot of lemons. Jalifornia Uitrogr. 22 (1): 14-15, 17- Nov. 1926. 3- Fawcett, H. S. Alternaria problem in relation to navel oranges. California GCitrogr. 12 (1): 40-41. Nov. 1926. Ae) Hawkins; Ll. As, and W. R- Barger. Cold storage of Florida grapefruit. U. S. Dept. Agr. Bul. 1268: 16s 1926. 5- Read, F. M. The storing of lemons. Jour. Dept. Agr. Victoria 2A: 292-303. May 1926. 6. Rose, De il., and L. F. Butler. Pleospora rot of lemons and apples. (Abstract) Phytopath. 17: 47. Jan. 1927. a Citrus Pruits \ FOOT ROT ATTRIBUTED TO PHYTOPHTHORA TERRESTRIS SHERB. . Florida: General; affcets chiefly the sweet orange sccdling groves. (Rhoads) Sanitation appears to be a fairly eifective control measures The best apparent results follow treating the affceted parts with a wash made of bluestone snd sada lyc, applied two or more times at intervals of six months. (Winston) Porto Rico: A form of gummosis or foot rot of unknown causation is common and sometimes scrious. Good results follow cutting out end painting with a mixture of tar and carbolincum. (Cook) Recent litcraturc 1. Rhoads, Arthur S. A new method for treating foot rot. Amr. Fruit Grower Mag. 46 (11): 7, 24. Nov. 1926. GUMMOSIS AND BARK DISUASES DUE TO VARIOUS ORGANISMS Botrytis cinorea Pers., Botrytis gumosis, Cealifomia - see Dothiorella. Diplodia natalensis Ell. & Hv., dic-back, Porto Rico. Diplodia sp., Diplodia gummosis was of the usual moderate importance in California, lemon being most susccptible and ormnges slightly so. (Fawcett) Dothiorella ribis (Fekl.) Sacc., Dothiorclla gummosis and Botrytis gummosis were reported from. Crelifomia as occurring sceettcringly ond being of moderate importance, lemon being most susceptible and orange slightly so. (Fawectt) : Phomopsis californica Pawc., decorticosis or shvll—bark Was moderately important in attacking trees after.they are 10 to 15 years old. Lemon is the only susceptible commercial type of citrus, the Bureka variety is very suscep— tible and the Lisbon is susceptible in @alifornia. (Fawectt) of usual prevalence and generally distributed in California. Bark infection was favored by April rains end moderate temperatures, and later the lower leaves and twigs were attacked. Trifoliata root stock is immune, sour orange is very re— Sistant, sweet orange and grapefruit are susceptible, and lemon is very suscep- tible (Fawcett). In Arizona this disease was found to have damaged a number of large grapefruit trees where debris had accumulated above the bud unions and Where there was an almost constant supply of waste irrigation water. (Arizona News Letter) Recent Jiterature 1. Petri, L. Azione tossica della calciocianamide sulla Blepharo- spora cambivora e la Pythiacystis citrophthora- (The toxicity of calcium cyanamide to Blepharospora cambivora and Pythiacystis citrophthora. ) Boll. R. Staz. Pat. Veg. 6: 135-138. 1926. Citrus Pruits eis) OTHER PARASITIC DISEASES Armillaria mellea (Vahl) Quel., root rot, California. Capnodium citricolum Vente , sooty mold, Florida ~— Control of insect pests liminates sooty mold (5 ee Texas. ‘Porto Rico — Quite common and necessitates ashing the fmit. (Cook) : Cephaleuros virescens Kunze, alleged leat spot. Porbo Rico. Colletotrichum glocosporisides Peonz., to which anthracnose and withertip are ttributed. In Florida, anthracnose was rather prevalent on grapefruit dur ing Pring on dead ripe fruit in many sections, particularly so on ridges and locations ubjected to extremes of drought and wet (Winston). Less than usual on twigs and eaves in Califomia with slight damage because of absence of contributing condi- ions such as frost, wind, etc. ‘It also causes a fruit rot of moderate to slight moortance Pieent). Porto Rico. Epiphytic higher plants of many carey Ponto Rico, orn of any importance nless very abundant, and can be controlled by removal. (Cook) Gloeosporium limetticolum Clausen, withertip of limes, Florida ~ Affects ey lime trees wherever they are growm throughout the state (Rhoads). Porto Rico - ecasional ly found on lime trees, usually very serious where it occurs. (Nolla)} Tylenchus semipenetrans Cobb, citrus nematode, was reported for the first e from Arizona in two grapefruit orchards in Maricopa County, apparently not ing seriously affected the trees. (Streets) ent literature fe MeMecme ite! Oe, end) Ha is: Lee. Citrias: disicasés and their control. New York, McGraw-Hill Book Co-., Inc. 1926. 2. Fulton, He R. Relative susceptibility of citrus varieties to eas by Gloeosporium limetticolum Clausen. Citrus Ind. WO} e 13, 17, 24-25. Aug. 1926. Eee heriand, S$. C« Withertip disease of limes. Suggestions for its control. Trop. Agriculture 3; 74-75. Apr. 1926. NON-PARASITIC DISEASES AND INJURIES Blight or wilt, caused by deficient or irregular water supply, Florida - lost prevalent in thirsty soils, very deficiont in organic matter, especially in the older groves on rough lemon root stock. The addition of organic matter to the soil seems to be the most promising line of treatmmt (Winston). In certain of the heavier soil types with normally high water table injury from draght was very Serious in May. Some young groves showed 50 per cent of the trees completely ‘“defoliated and there has been excessive drop of fruit from mature citrus trees (Kuntz). Wilt continues to be of considerable importance in the groves sof cextaim ioedittaes, but causes slight loss for the state as a whole (Rhoads). Porto Rico- A few reports have been reecived- (Cook) 100 ! Citrus Fruits Spray injury, Florida - Bordeaix-oil burn caused moderate loss, grapefruit being most susceptible md oranges and tangerinss somewhat less sos There was no definite correlation between weather conditions «id this injury. A large ex- cess of lime in the Bordearx tends to reduce injury. ‘he cGegree of injury does not vary with the soveral types of emulsifier. CUsclcium taseinate added ta the Bordeaux— oil reduces the injury but dws not eliminate it. Refined white oils are about as risky as red oils (Winston). Porto Rico - In varying degrees depending on work-— manship, usually slight. (Cool:) Recent literature 1. Bartholomew, E. T. Internal decline of lemons. III. Water deficit in lemon fruits caused. by excessive cvaporation. Amer. Jour. Botta; If: MO2.) AG2b. ye end W. Je Roobins. Internal decline (cndoxerosis) of lemons. IV. The carbohydrates in the peel of healthy and endoxcrotic fruits. Amer. Jour. Bot. 13: 342-454. 1926. 4. Braunton, Hi... June drop of oranges. California.Gylts 67: 56. Salah, 92os 4. Rhoads, A. 8S. Investigations on citrus "blight", wilt or leaf curl in Florida. (Abstract) Phytopath. 17: 58-59. Jan. 1927. 5. Pregress report) on, ci.brus blight .investigations. Proc. Florida State Hort. Soc. 39 (1926): 143-146. 1926. 6. Surry, Gs, degy andy Ls Diy Batch elors.9 Citrus) culture, an, central: California. California Agr. Exp. Sta. Bul. 405: 1-24. Aug. 1926. June drop: p.» 20-21. DISEAS HS O;> UNKNOWN CAUSATION Die-back and_ammoniation, cause unknown, is on the wane in Florida due to more judicious use of fertilizers, less cultivation, and the prompt use of blue- stone as a soil application whenever die—back symptoms appear. Old seedling orange trees are most. likely to show symptoms on the fruit while grapefruit shows the symptoms most usually on the vegetative parts (Winston). There was slicsht damage in scattered localities in Califomia.: (Favcett) False melanose or greasy spot, cause unknown, Porto Rico. Gummosis, cause unknown, Florida — Less prevalait now than several vears ago.. lemons and seedling oranges are most susceptible. The usual treatments are of questionable valuee Possibly gummosis my be induced or aggravated by cold injury. (Vinston) i 101 ‘Citrus Fruits to Avocado Mottie leaf or foliocellosis, cause unknown, is a disease of major impor- tance in Califomia but is probably gradually growing less because of better gen- eral management of orchards (Pewcett). Common and occasionally serious in Porto Rico. (Cook) Nail head rust or Scaly bark, caise unknown, Florida -— Is on the decrease and seems to disappear in my particular grove as soon as it begins to receive Ordinary spraying and care (Winston). Affects chie ofly the sweet orange, cnd is of importance only in certain loctlities throughout the citrus belt (Rhoads). Arizona — A slight amount on a few trees in one locality. (Streets) , Psor9sis, cause unknown, is less prevalent in Florida than some years a&g0-6 Ht is most prevalent in droughty locations. No treatment now in use gives Ssatius= factory results (Winston). Tangerines are especially susceptible (Rhoads). In California it is ery important and generally distributed on trees 8 to 10 years Of age. Lemon is immunc, grapefruit and tangerine are suscept ible, end sweet Brange Varietics are very Susceptible. (Fawcett) Recent literature i. Carne, W. M...Exanthemas (A dic-back of orange trees.) Jour. Dept. Agr. Western Australia II, 3: 59-62. 1926. 2. Doidge, Ethel I. ee (psorosis) OL Clirus trees. | JOU. Dept. Agr. South Africa 12: 61-67. 1926. Av O CAA DO Cephaleuros virescens Kunze, algal leaf spot. Porto Rico. Colletotrichum glocosporioides Penz. caused rot of m.ture fruits, especi- Welly of the Puerte variety, in Florida (inwicbomlin ia Porto: Rico it was severe on Some seedling trees and of little importence on others. (Cook) Diplodia sp., stem disuvase, was reported from Porto Rico as killing twigs | and seedlings, being most severe on seedlings grown in heavily mamred soils. (Cook) -Pestalozzia Sp., blight, Texas. i Pestalozzia guepini Desm. was reported.to kill twigs end seedlings in Porto Rico, being most severe on seedlings that had been grown in heavily manured Boils. (Cook) | Phyllachora gra peli Rehny , tar spot. Porto Rico. Pythiacystis citrophthora BE. H. & R. E. Sm., bark disease. California. Rhizopus sp. llost active cies rot of ripe avocado fruit in Cali- | aia (Horne) : sphaceloma sp., scab, was gener al in Florida causing scrious leaf spotting and fruit blemish. (Fulton) Recent litereture 1. Horne, W. T. Avocado frit decays. Ann. Rep. California Avocado Assoc. 1925-26: 96-99. 1926. 102 Avocado to Banana 2. Smith, C. 0. Blast of avocados - a bacterial disease. Ann. Rep. California Avocado Assoc. 1925-26: 72-74. 1926. Se Blest of avocados — a bacterial disease. Califomia Citrogr. 11: 163. Mar. 1926. 4. Similarity of bacterial diseases of avocado, lilac, md citrus in California. Phytopath. 16: 235-236. MANGO Colletotrichum gloeosporioides Penz., canker and fruit rot, was.reported as common in:Porto Rico and very severe in some cases (Cook). The same fungus was reported as causing blossom blight during moist weather throughout the island, and as producing serious withertip in one locality. (Nolla) Diplodia sp.-, withertip. Porto Rico. Meliola mangierae Harle, ‘sooty mold. Porto Rico. Oi. EV Bacterium savastanoi EFS., knot or tubercle disease. California. (C. 0. Smith) aba tae Monkey face, probably physiological, was less severe in California than during the preceding year, cadsing moderate loss. It is generally distributed on the Barouni variety. ‘There is distortion of the blossom @md with development of corky tissue in the flesh, correlated with degéneration of the embryo. (Rawlins) Soft nose, probably physiological, was less severe in California than during preceding year, causing moderate loss. It is generally distrilmted, but confined to the Sevillano variety. It develops after fruit begins to color. Young trees, heavily pruned, md heavily irrigated trees appear to produce most affected fruit. The fruit is soft at the end, shrivels end spoils. (Rawlins) B-A NANA Fusarium cubonse EPS., wilt, was very destructive throughout Porto Rico. (Cook) : Glocosporium musérum Cke. & Massee, fruit rot, was very common bit not important on over-ripe fruit in Porto Rico. (Cook) Papaya to Pig LOA AP ay A Glomerella cingulata (Ston.) Spauld. & Schrenk, fruit rot, occasionally severe in Porto Rico. (Cook) Pucciniopsis caricae Harle, leaf spot. Porto Rico. Florida. Gy UM Nip BA Clitocybe monadelpha (Morg.) Sacc., root rot, observed occasionally in Florida. (Rhoads) Glomerella cingulata (Ston.) Spauld. & Schrenk, fruit rot, was common and “severe in Porto Rico. (Cook) DA Graphiola phoenicis (Moug.) Poit., rust. Porto Rico. Texas. Bastiat | Botrytis cinerca, Botrytis rot, apparently the most serious rot of this ‘fruit in Galifornia. (Horne) | Penicillium expansum Link, rot, was reported as abundant on ripening fruit in Califomia. (Horne) LaiG: Caconema radicicola (Grecf) Cobb, root knot. Texas. i Ceorcospora spp-, leaf spot. Prevalmt but unimportant in Texas. Collctotrichum sp-, anthracnose. Tcxas. Corticium salmonicolor Berk. & Br. Slightly important in Florida. Macro phoma fici Alm. & Cam., canker. Loss a trace in Texas. Qzonium omnivo rum camel root rot. Arizona and Texas. Loss 2 per cent in black lands of Texas. uhizoctonia TRE sitlieinobRA Matz., lcaf blight. Mississippi. ‘@lorida. Sclerotinia sp., foot rot. Texas. ; Ceoroteclium fici (Cast.) Arth., rust. In Texas unimportant in sprayed Orchards but in unsprayed orchards tho loss often 100 per cent. Pronature dropping (phys siological). Prevalent, with loss of 0.5 per cent in Texas. 104 Fig to Pecan souring of fruit (cause unknown). Reported from Texas where Taubenhaus reports the loss to be 40 per cent. , He states that the disease is associated with fruit punctures made by the cotton leaf mothe Caldis (1) and Smith (2) discuss the relation of certain insects, acting as carriers of a yeast, to infcc- Beton of fig’ fruits, Recent litcrature 1. Caldis, P. D. Souring and int ornal rot.of the figs. -—Paciiae Rural Press 111: 500. Apr. 17, 1926. 2. Smith, R. Pig diseases and their control. Pacific Rural Press 112: 575. Nov. 20, 1926. PO UME GR AON A Cercospora lythraccarum Heald & Wolf, lsaf spot. “Ruported for the first time in Alabama. ae PEGAN SCAB CAUSED BY FPUSICLADIUM EFFUSUM WINT. The situation with regard to pecan scab is well summrizcd in a report of J. B. Domaree to the Plant Disvase Survoy. "The prevalence of pocan diseases during the scason of 1926 as observed in several places in southeastern United States was not greatly diffcront from that of previous ycars- Scab caused by Fusicladium effusum Wint., however, is undoubtedly gradually increasing in importance. While at one timc the disease in an epiphytotic form was confined to one or two varieties, the causative fungus is now capable of s.riously attacking sovceral varictics of the host. There is evidence that this process of adaptation is still going one During the carlicr days of the pecan industry (20 or 25 years ago) the Delm:s and Georgia and some Toxas varictics were the only oncs that scomed to be sus- ceptible. Later, other varictics, such as Van Deman, Alley, schlcy, and Pabst were added to the susceptible list. The fungus now scoems to be adapting itsclf to other varictics once thought \ ; is Recent 105 Pecan to be quite resistant. Of the formerly considered resistant varieties Moneymaker was found to be susgeptible at Jeanerette and Whileville, Louisiana, and Selma, Alabama. Scab infected nuts of the Stuart variety were collected this season by Wedgworth in Mississippi, and Boyd at Thomasville, Georgia. The fungus has been attacking the variety Frotscher slightly in south Georgia and north rlorida for the past four or five years and some loss of the variety occurred in south Georgia and Louisiana this season. Pecan scab caused a total loss of the Schley, Pabst, Delmas, Georgia, ‘and Alley varieties in several thickly planted areas of north Florida, and the south» portions of Georgia, Alabama, Mississippi, and Louisiana this Season. Control measures under the direction of the U. 8S. Department of Agriculture are keeping pace with the gradual extension of the discase. Two to four applications of Bordeaux mixture applied during May, June, and July, if supplemented with Orchard sanitary measures, will effectively control pecan scab. Four to six applications of monohydrate copper-lime dust con- trolled the disease very satisfactorily on the Schicy and Alley. varieties in south Georgia this season. Fighting the disease — with dust is mceting with considerable favor and as a result of experiments conducted this past year extensive commercial dust-— ing will be practiced next season." a literature 1. Anderson, H. W. Discases of nut crops in the northern United States. Rep. North. Nut Grow. Assoc. 16 (1925): 38-45. 1926. 2. Blackmon, G. H. Preliminary report from the Florida Agricultural Experiment Station on pecan investigations. Proc. Georgia-Florida Pecan Grow. Assuc- 20: 40-44. 1926. 3. Boyd, 0. C. Report on the experiment of 1925 for pecan scab control at Baconton, Georgia.’ (Abstract) Phytopath. 16: 64A-645- Sept. 1926. a , A. Demaree, J. B. Recent developments regarding pecan discasos,. Proc. Georgia~Florida Pecan Grow. Assoc. 20; 62-65. 1926. Ds a The pecan scab fungus. (Abstract) Phytopath. 16: 642-643. Sept. 1926. 6. and J. R, Cole. Commercial contro} of pecan scab. U.S. Dept. Agr. Dept. Circ. 386: 1-8. June 1926. {> Nolen, R. E. Pecan scab. Florida Agr. Exp. Sta. Bul. 101: 251-276. May 1926. . 106 ' Pecan OTHER DISEASES Bacterium tume fachens EVS. & Towns., crown gall. ‘Texas. Cercospora fusca (Heald & Wolf) Rand, brow leaf spot. Reported from North Carolina; southern Georgia - loss a trace; and Texas - loss 0-5 per cent. ie. Be Reyes on the Office of Fruit Disease Investigations,. in a report to the Plant Disease Survey states, "The Céercospora leaf spot makes its appearance about midsummer. It becomes quite plentiful during the latter part of the season and is found in most. orchards. It is not considered important in thrifty trees. In prevalence it was not noticeably different this season than in former years." Microsphaera alni (Wallr.) Wint., powdery mildew. Very prevalent in Texas causing premature shedding of fruit. Loss 5 per cent (Taubenhaus). Loss a trace in southern Georgia. Usually common on isolated or city trees; also common on Mobile, Success, and Pabst varicties. (Boyd) Ozonium omivorum Shear,. root rot. Texas. Phyllosticta caryac Pke, nursery leaf blight, was. less prevalent during 1926 than it has been for several years. Very few nurserymen considered it suf- ficiently serious this scason to antes any control measurese During favorable seasons the disease is serious in nurserizs (Demarce). xeported from Texas by Taubenhaus. Kernel spot (insect puncture). Repor ted tae0 Gcorgia and Arkansas. Ac-— cording to Boyd, the loss in southern Georgia was estimated at about 4 per cent, there being a 50 per cent loss in some Angst ie : Black pit (undet.) Reported from South Carolina and Gcorgia. Boyd esti- mates the loss in southern Georgia at 4 per cent. He states. that the Sehley and Frotscher varicties suffercd most in 19 26, especially in the southern part of the state. Some trees lost 5 to 25 per cent of their crop. ditule “cate? aga roport to the Plant Disease Survey, Demaree makes the follow ing observation: "The known distribution of little leaf of pecans is from Savannah, Georgia, south to:Miami, Florida, and west to Biloxi, Mississippi. Recently the writer found the disease present on trees near an,old plantation homestead cight miles from Charleston, South Carolina. Dr. S. G. Lehmen showed the writer specimms of typical little leaf that he had collected in an orchard near Raleigh, North Carolina. Heretofore, little leaf had only. been found on trees that had been planted in fertile garden soils within city limits. The Raleigh specimen is the only one known by the writer to have bee collected from trees SnowLng under orchard conditions." See also Demarec (2) sha . Rosette (undet.) Reported from South Carolina, Georgie, Texas, and Ari- zona. A loss of 10 per cent was reported for southorn Georgia by Boyd. Demarec in his report to the Plant Disease Survey states: "A smaller percentage of pecan trees are affected. with rosette now than ten years ago. MeMurran reported in 1919 (U. S. Dept. Agr. Bul. 756) that 10 to 20 per cent of the pecan trees planted in or- chards in samtheastern United States were affected with this disease. The smaller percentage of rosetted trees now present may be attributed SS i 107 Pecan to Walnut . to several factors, as follows -- better care of orchards, judicious use of fertilizers, the general practice of plowing under leguminous cover crops, and greater discrimination in the selection of new orchard sitess During the pioneer days of the pecan industry many orchards were planted on impoverished cotton lands, deep sandy. landsS or eroded hillsides. Such soils as a rule develop rosetted trees. The selections. of such undesirable soils for orchard sites aré now very gemerally avoided, conse- quently a smaller percentage of rosette affected trees develop in the younger orchards." (See also Skinner and Demaree (4) mrecent literature is Videir, He Ss: Black pit of pecan. Amer. Nut Jour. 26: 6, Ve Jan. 19217. ae a9, J. Be Little leaf discase of Pecans. Phytopath. 16: 277-203 » 1926. Ae Recent developments regarding pecan diseases. “Proc. Georgia-Florida Pecan Grow. Assoc. 20: 62-65. 1926. A. Skinner, J. J., md J. B. Demaree. Rela tion of soil conditions and orchard management to the rosette of pecan trees. Wes. Meme Mere Bale 1570: I-16. 1926. Be ee 1 Sw A LN UT Bacterium juglandis (Pierce) EFS., bacterial blight. Reported from Dela- Ware, Washington, Oregon, and Califomia. California - Epidemic, loss about 60 per cenit. The reason for the epidemic is not clear, since both temperature and rainfall were normal. The Franquette and Hureka varieties were resistant, while Payne, Placentia, Chase, Concoru, and others were susceptible. Although generally Considered to be resistant the Eureka variety in 1926 showed a loss of 40 per cent and the Mayette a loss of 50 per cent (Rudolph). Oregon - Experience shows that even our most favored commercial variety, the Franquette, often suffers severe losses, It is estimated that in 1925 and in 1926 at least half the crop that set On the trees was attacked by blight. These two years are probably for Oregon i about the worst years on record. (Barss (1) Gnomonia leptostyla (Pr.) Ces. & DeNot., anthracnose. In Delaware, accord— ing to Adams, anthracnose was very severe on the black walnut and butternut, caus— ing defoliation. English walnuts also shoved infection but there was no defoli- ation. The disease was reported also from Connecticut and Missourle 108 Walnut to Coconut Recent literature 1. Barss, H. P. Bacterial blight of the walnuts. Oregon Agr. Coll. Exten. Serv. Circ. (mim.) 229: 1-4.. Dee. 1926. 2. Gard, M. Le pourridic du noyer. Traitements et mesures preventifs. Rev. Vitic.64: 188-191. 1926. ALMOND Cladosporium carpophilum Thuem., scab. Reported for. the first time in Connecticit by Clinton. : Coryncum beijerinckii Oud., blight. Loss 4 ner cent in Califomia, ac- cording to Milbrath. ; i Sclerotinia fructicole (Wint.) Rehm, brown rot.. Loss estimated as 30 per cent in Stanislaus County, California. There was much rain during and follow- ing the blooming period and mild temperatures prevailed during the time of infec- tion. Thc Jordan, Texas, and Langucdoc varieties were considered to be resis tant but the [I.X.L., Non Pareil, and especially the Drake and Ne Plus Ultra were sus-— cep tible.. (Rudolph) : Bacterium sp., blight. “Gereral in Oregon and causing large losses in some nurserics and in some young plantings. Phyllactinia;corylea (Pors.) Karst., powlery mildew. Present in Washington Recent: Llitcrature 1. Berss, H. P. Bacterial blight of filbort. Orcgon Agr. Coll. Exten. Serv. Circ. (mim.) 230: 1-6. Doc. 1926. Collctotrichum sp., snthracnosc.e' Florida - Quite commonly found in nur- series on young plants and apparently of soe importance. (Seal) —~ . Diplodia sp., leaf spot. Florida - Not uncomion in the nurseries in the southeastern section of the state. Of little importence. (Seal) Pestalozzia sp., leaf spot. Florida - Gneral in the smtheastern part of the state. Of little importence. (Sval) Phytophthora palmivora Butlcr, bud rot. Porto Rico -— The campaign for the extermimtion of this discase by the destruction of diseased trees has been very successful. (Cook) Re are 109 Coconut Phytophthora sp-, bid rot. Florida — Gencrally distributed over the south- eastern part of the state. Of mjor importance. (Seal) . Thiclaviopsis paradoxa (DeScyn.) Hochn., fruit fall. Rare in Porto Rico. (Cook). Seel reports Thiclaviopsis sp. on leaves to be general and of some im-— Mertance in the Southeastern section of Florida. Recent literature 1. Mendiola, Ne B., amd G. O. Ocfemia. The work of brivding disease resistant crop plants at the Colloge of Agri- culture at Los Banos. Philippine Agr. 15: 117-120. Aug. 1926. 2e Sharples, A» Discascs of coconut palms. Maleyan Agr. Jour. 1A: 65-733 91-95. Mar. 1926. %-. Teodoro, N. G Coconut diseases and their controle Philippine Agr. Rev. 18; 585-592. 1925. A. Tucker, ©. Me. Phytophthora bud rot of coconut pelms in Porto Rico. Jour. Agr. Res. 42: 471-490. 1926. 5. Walters, H. Ae Report of the Agricultural Department, St. Incia 1924: 1-30. 1926.