REPORT OF THE nORTICVLTVRIST 111 



SESSIONAL PAPER No. 16 



FUNGOUS DISEASES AND OTHER INJURIES. 



1'lie following fungous diseases and other injuries are thought worthy of special 

 mention this year : — 



Sooty Fungus or Fly Speck Fungus (Leptothyrium pomi). My attention was called 

 to this disease by Mr. Alex. McNeill, Chief Fruit Inspector for the Dominion. It is not 

 a common disease in Oi\tario, Ijut was more prevalent than usual in the vicinity of St. 

 Catharines this year. The following quotation from a letter received from Mr. Robert 

 Thompson, St. Catharines, Ont., gives information regarding it. He writes : ' We have 

 had it here in very low lying orchards, in flats or creeks or orchards in valleys in damp 

 seasons, but never very much. This season it is more prevalent. It has always been 

 called by the bu3'^ers in Montreal 'The Cloud' and the fruit is called ' clouded fruit '. 

 This disease also occurred to a limited extent in the orchard of Mr. D. J. McKinnon, 

 Grimsby, Ont., who submitted a specimen of affected fruit for examination. The Sooty 

 Fungus is more prevalent in some of the Eastern States than it is in Canada, the variety 

 of apple most ah'ected being the Khode Island Greening. 



The disease appears on the surface of the skin in irregular, black, sooty -like patches, 

 which look not unlike splashes of ink. Fortunately, it is easily controlled and one spray- 

 ing with Bordeaux mixture when the apples are about the size of hickory nuts is said to 

 prevent the spread of it. 



Russetting of Apples. — The skin of apples russetted badly in 1902, from Prince 

 Edward Island westward to the province of Ontario, and there has been much discussion 

 as to its cause. At the Central Experimental Farm a few varieties are russetted every 

 year, but this season more kinds were affected. 



It is our opinion that the russetting was due to spraying and that some kinds are 

 more subject tlum others. This year, by mistake, a very strong copper sulphate mix- 

 ture was put on a few trees here. The fruit on these was much more russetted than on 

 those which received the regular mixture, showing that the strong mixture had caused 

 russetting. It is our belief that owing to the exceptionally cool season the skins of 

 apples were not as tough as usual, and that the ordinary Bordeaux mixture caused the 

 russetting which occurred in different parts of the country. Statements liave been 

 made that the fruit was russetted on both sprayed and unsprayed trees in orchards, and 

 others have said that the russetting only occurred where the trees were sprayed. Closer 

 observations will be made next year. 



Dropping oj Apple Leaves. — The leaves of apple trees dropped badly this year, 

 especially during the month of July. This dropping occurred in the Maritime provinces, 

 in the province of Quebec and also in Ontario. It was also common in the eastern 

 states. Small brown patches first appeared on the leaves which gradually became yel- 

 low and dropped ofl". The brown patches looked as if they were caused by scald. They 

 were put under a high power microscope at the Central Experimental Farm and no trace 

 of disease could be found. In one orchard visited it was noticed that there was little 

 or no injury where the leaves did not get the direct rays of the sun. This injury 

 occurred in both sprayed and unsprayed orchards. There is a leaf disease in the United 

 States which causes injury somewhat like this, but as no disease was to be found the 

 only present explanation of the dropping is that it was caused by unusual climatic con- 

 ditions. 



Black Rot of the Cabbage. — Since 1899 the cabbages at the Experimental Farm 

 have been affected with the disease known as black rot and this year they were badly 

 injured by it. The mid season and late varieties have been most affected. This disease 

 has only been recognized since 1889, when it was found in Kentucky, but it has become 

 very troublesome within the past ten years, and now occurs in the United States in a 

 great many states and does serious damage to this vegetable. It has not, however, been 

 often reported in Canada. The only report this year was from A. Bangel, Nicolet, Que., 

 who wrote that it was doing much damage to his cabbages. It attacks cauliflowers, 

 Brussels sprouts and turnips and some other allied vegetables. 



