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THE CANADIAN HORTICULTURIST 



pedigreed plants. But such plant breeders 

 are few." 



" There are many of our Canadian straw- 

 berry growers who are growing their plants 

 on good soil, under good cultivation, and 

 who are careful to select healthy, vigorous 

 plants from new plantations, who can fur- 

 nish just as good plants as any of the adver- 

 tisers who make such extravagant claims 

 for their plants grown in no better way. I 

 am glad that you are taking this matter up 

 in The Horticulturist. I have heard of 

 Canadian growers who have been disap- 



pointed in these so-called pedigree plants 

 obtained from the States, when they might 

 have got as good, if not better plants from 

 some near-by "grower or neighbor. It is 

 well that our fruit growers are anxious to 

 get the best that can be obtained, yet they 

 must remember that varieties are developed 

 Or bred up by the few who can give the at- 

 tention to crossing and' breeding of plants, 

 while the general grower is concerned more 

 about the selection and growing of thrifty, 

 vigorous plants of the varieties so estab- 

 lished." 



BLACK ROT OF GRAPES * 



PROF. W. LOCH HEAD, O. A. C, GUELPH, ONT. 



PERHAPS some of our Ontario grape 

 growers are wondering if the 

 methods which are so effective in. Ohio in 

 controlling the grape rot can be relied on 

 in Ontario. We are not able to answer this 

 question definitely on account of the new- 

 ness of the situation and the absence of ex- 

 perimental work for a longer period than 

 one season, but on account of the similarity 

 of situation of the two grape belts, both as 

 to soil and climate, we would be justified in 

 answering in the affirmative. Both regions 

 are grape regions on account of their pecu- 

 liar position to one of the great lakes, both 

 being strongly influenced by the presence 

 of a large body of water to the north. 

 Moreover, the experience of Mr. W. H. 

 Bunting this past season in controlling a 

 bad attack of black rot in his large vineyards 

 near St. Catharines would lead us to believe 

 that the disease could be controlled even 

 more effectively the coming season. Mr. 

 Bunting sprayed persistently and carefully 

 from early spring to the middle of August 

 and was rewarded with a good marketable 

 crop. Like myself he believed thoroughly 

 in early spraying, even while the vines are 

 yet dormant, for the reason that the early 



spores are prevented from effecting an en- 

 trance into the tissues. In the great ma- 

 jority of cases this reasoning stands true, but 

 apparently it is not true with the black rot, 

 for the Ohio experiments carried on for 

 three years in succession showed conclu- 

 sively that the fungus can be kept out en- 

 tirely and absolutely even when the first 

 spraying is delayed until the last week in 

 May or the first week in June and when the 

 young shoots are nearly eighteen inches long. 



It may 'be that the winter spores are not 

 set free from their cases until the shoots are 

 of considerable length and after the shoots 

 have come out of their dormant condition. 



It is very evident that besides persistent 

 and careful spraying clean culture is a very 

 essential factor in the control of black rot. 



A study of the reproduction of the fungus 

 shows the presence of spores which winter 

 over in the dead leaves, diseased shoots, and 

 mummy fruit. It is important, therefore, 

 that as many of the diseased leaves, shoots 

 and grapes as possible be collected and 

 burned, or buried deep by the plow so that 

 there is no likelihood of the spores reaching 

 the surface to be scattered by the wind. 

 The most fruitful source of infection is the 



* Extract from an address delivered at the annual convention of the Ontario Fruit Growers' Association. 



