CIHM Microfiche Series (Monographs) ICMH Collection de microfiches (monographies) Canadian Institute for Historical Microreproductions / Institut Canadian de microreproductions historiques .MSsssmsmiSi^im^sr^immssi^smmfrmmiiL:^ '^^w'^isimimm ^&i7^^£^iTQ,ti^'{i£ f-- Technical and Bibliographic Notes / Notes techniques et bibliographiques The Institute has attempted to obtain the best original copy available for filming. Features of this copy which may be bibliographically unique, which may alter any of the images in the reproduction, or which may significantly change the usual method of filming are checked below. n Coloured covers / Couverture de couleur I I Covers damaged / Couverture endommag6e □ Covers restored and/or laminated / Couverture restaur^e et/ou pellicul^e I Cover title missing / Le titre de couverture manque I I Coloured maps / Cartes geographiques en couleur □ Coloured ink (i.e. other than blue or black) / Encre de couleur (i.e. autre que bleue ou noire) [~ 1 Coloured plates and/or illustrations / Planches et/ou illustrations en couleur Bound with other material / Relie avec d'autres documents Only edition available / Seule Edition disponible y I Tight binding may cause shadows or distortion along interior margin / La reliure serr^e peut causer de I'ombre ou de la distorsion le long de la marge interieure. n n Blank leaves added during restorations may appear within the text. Whenever possible, these have been omitted from filming / II se peut que certaines pages blanches ajoutSes lors d'une restauration apparaissent dans le texte, mais, lorsque cela ^tait possible, ces pages n'ont pas 6t6 film6es. Additional comments / Commentaires suppl6mentaires: L'Institut a microfilm^ le meilleur exemplaire qu'il lui a et6 possible de se procurer. Les details de cet exem- plaire qui sont peut-Stre uniques du point de vue bibli- ographique, qui peuvent modifier une image reproduite, ou qui peuvent exiger une modification dans la m6tho- de normale de filmage sont indiqu6s ci-dessous. Coloured pages / Pages de couleur I I Pages damaged / Pages endommagees D Pages restored and/or laminated / Pages restaur^es et/ou pellicul^es Pages discoloured, stained or foxed / Pages decolordes, tachet^es ou piquees I I Pages detached / Pages detach^es I /] Showthrough / Transparence I I Quality of print varies / D D n Quality in^gale de I'impression Includes supplementary material / Comprend du materiel suppl^mentaire Pages wholly or partially obscured by errata slips, tissues, etc., have been refilmed to ensure the best possible image / Les pages totalement ou partiellement obscurcies par un feuillet d'errata, une pelure, etc., ont 6t6 film^es k nouveau de fafon k obtenir la meilleure image possible. Opposing pages with varying colouration or discolourations are filmed twice to ensure the best possible image / Les pages s'opposant ayant des colorations variables ou des decolorations sont film^es deux fois afin d'obtenir la meilleure image possible. This item is filmed at the reduction ratio checlted below / Ce document est 1i\mi au taux de reduction indiqui ci-dessous. 10x 14x 18x 22x 26x 30x J 12x 16x 20x 24x 28x 32x The copy filmed here has been reproduced thanks to the generosity of: Library Agriculture Canada The images appearing here are the best quality possible considering the condition and legibility of the original copy and in keeping with the filming contract specifications. Original copies in printed paper covers are filmed beginning with the front cover and ending on the last page with a printed or Illustrated impres- sion, or the back cover when appropriate. All other original copies are filmed beginning on the first page with a printed or illustrated impres- sion, and ending on the last page with a printed or illustrated impression. The last recorded frame on each microfiche shall contain the symbol — ♦- (meaning "CON- TINUED"), or the symbol V (meaning "END"), whichever applies. Maps, plates, charts, etc.. may be filmed at different reduction ratios. Those too large to be entirely included in one exposure are filmed beginning in the upper left hand corner, left to right and top to bottom, as many frames as required. The following diagrams illustrate the method: L'exemplaire film* fut reproduit grdce A la gintros'ni de: Bibliothjque Agriculture Canada Les images suivantes ont M reproduites avec le plus grand soin, compte tenu de la condition et de la nettet« de l'exemplaire film*, et en conformity avec les conditions du contrat de filmage. Les exemplaires originaux dont la couverture en papier est imprimie sont filmis en commen9ant par le premier plat et en terminant soit par la derniAre page qui comporte une empreinte d'impression ou d'illustration, soit par le second plat, selon le cas. Tous les autres exemplaires origiriaux sont filmis en commen9ant par la premiAre page qui comporte une empreinte d'impression ou d'illustration et en terminant par la derniire page qui comporte une telle empreinte. Un des symboles suivants apparaltra sur la derniire image de cheque microfiche, selon le cas: le symbola — ► signifie "A SUIVRE". le symbole V signifie "FIN". Les cartes, planches, tableaux, etc.. peuvent fttre film«s « des taux de reduction diffirents. Lorsque le document est trop grand pour «tre reproduit en un seul clich*. il est film* A partir de I'angia supirieur gauche, de gauche * droite, et de haut en bas, en prenant le nombre d'images n*cessaire. Les diagrammes suivants illustrent la m*thode. 1 2 3 MIOtOCOfY RESOLUTION TEST CHART lANSI ond ISO TEST CHART No 2| 1.0 I.I 1.25 1 2B 1 2.5 1^ 112.2 1 4.0 1.4 2£ 1.6 ^ APPL IE D INA^GE Inc ^5r Tfi^i East WQ'" S('e*t ^S Roc^-.es'c New 'oft< 1*609 USA JSS (.ne) 482 - 500 - Pnone ^= (^16) 288 - 5989 - fa. mac] < nr bi ihouj luicl li-od liici ; u BLACK LEG DISEASE OF POTATOES ! ■ '-K BV PAUL A. MURPHY. H.A., M.K.C.S.I.. Assislaut in charge of Field Laboratory for Plant Pathology, Charlottetown, P.E.I. riiis disease of potatoes is, not very well known, altluiugh it is widespread in Canada, as in most countries where potatoes are grown, and does a great deal of harm in certain years. It appears in July as a rule — affected plants being of a light yellowish-green colour and sickly looking. They have little anchorage in the ground, and the under- ground part of the stem is attacked by a soft black rot which can be traced down into the set, where it arises. Diseased plants seldom produce any crop, and if they do the tubers rot as a rule, the infection passing into them from the parent plant. The affected tubers are moist and soft, often with a black cavity inside, or the whole of the flesh may be re'2.'-i.')4 EXHIBITION CIECULAR No. 82 (January, 1916.) ■^■v I ; I '1 I iJ i I ■i •i I'l.ATK A. -A piitiitM [ilaiit 'Ivinn ficmj an attack of I'lack-lf^;. Ii.--An infi-(t>-() •'liiH.t. Iilackciii-d liy tln' dist-ast- at l\n- base, tin- >o called "blark let;. " " C-K. — A iiiiriiluT i>f ixitatiii's, cut tliruui^li. sljowinj.' the disease » itliin the tlllHT, ( I'll,,!,, Ihi-niiiih tin i-ourtrfu of iJr. It'. A. Urtoii, I'. S. llr/il. nf A'.lf.) 8 Mole (o). Corrosive subliiuutc is rather insoluble and a small iiuaiitiiy of hot water should be used to dissolve it. Wooden or earthcnwurt- vessels only siioiild be used. Mote (!>). More than one batch of potatoes should not lie disinfcL'tod in the same solutiou of corrosive sublimate because it loses its strcnfctii (iiiiekly. The formalin solution may be used repeatedly. Note (c). Corrosive sublimate should not cost any more than liO cents ;in ounce Formalin should not cost more than 25 cents per pint. 4. Keep a jar of for.nalin solution of the same strtngtli at hunil with u spare knife in it when cutting seed, and if a tnl)er which shows traces of rot be met with, discard the whole tuber and dro)) tlie knife, with which it has been cut. into the disin fcctant and use the other one. 5. Do not grow potatoes in soil that needs drainiiiii. A wal soil favours the disease. The disinfection mentioned in (3) will not he etfeetive unless tiie selection described in article (2) be also carried out. Either of the treatments -riven is also i;ood for Common Scab, and to a less extent for Rhizoctonia and Powdery Scab, for which the corrosive siibliniati' i- lietter. These di.sease< aie capable of livin;^ in tin- >oil also. For further information aitply to the Dominion liotanist. Central Kxixrimentiil Farm. Ottawa. Read also- Potato Diseases Trajismitted hv ilio \'~c ,it rnMi\in