SPRAYING AGAINST THE BLACK ROT 



\V. H. BUNTING, ST. CATHARINES. 



1HAVE noted with considerable interest 

 the timely articles in The Horticulturist 

 on black rot of the grape, more especially 

 those from Mr. W. T. Macoun, of the Cen- 

 tral Experimental Farm, and Prof. Loch- 

 head, of the Ontario Agricultural College, 

 both of whom have been taking a lively in- 

 terest in the work of the fruit growers of 

 Ontario. As my vineyards have been inci- 

 dentally mentioned in these articles, I have 

 thought that I might add a word or two 

 emphasizing the conclusions arrived at. 



Spraying: on the Farm of Alex. Heazlitt, Adolphustown, Lennox County, Ont. 



The grape industry, which has reached 

 large proportions, and become a most im- 

 portant interest, is threatened with a serious 

 danger unless prompt measures are taken 

 to check the inroads of this fungus disease. 

 I have had evidence of the presence of the 

 rot for several years amongst the Rogers 

 varieties on sandy soil, and have been spray- 

 ing to some extent, but with indifferent suc- 

 cess, because the work was done in a spas- 

 modic way, and usually not taken up until 

 after the damage to the fruit became more 

 or less evident. It was not until 1901 that 

 symptoms of this disease were seen on the 



Niagara grape, but during that year it sud- 

 denly appeared when the fruit had attained 

 nearly full size but had not commenced to 

 ripen. An application of Bordeaux mix- 

 ture seemed to check it. There also ap- 

 peared that year what has become commonly 

 known as petrified grapes. The berry, in- 

 stead of ripening in the ordinary way, be- 

 came solid and opaque, assumed a dull grey 

 or greenish white appearance, and finally 

 dropped to the ground. 



In 1903, owing to peculiarly favorable at- 

 mospheric con- 

 ditions, black 

 rot spread ' so 

 rapidly, not only 

 over the Nia- 

 gara grapes, but 

 also affected 

 nearly all other 

 varieties and 

 was in evidence 

 in so many 

 vineyards it be- 

 came apparent 

 that a vigorous 

 campaign must 

 be commenced. 

 Conflicting re- 

 ports were re- 

 ceived of failure 

 or success in combatting the disease. In some 

 sections the growers pulled out their vine- 

 yards and turned their attention to other 

 crops. Others, by persistent effort, suc- 

 ceeded in controlling the disease and reaped 

 fair crops. I resolved on making a deter- 

 mined effort to fight the ro<t during 1904. 



The vineyard most seriously affected was 

 sprayed seven times ; four with the Bor- 

 deaux mixture (4-4-40 formula), twice with 

 the soda Bordeaux, using sufficient caustic 

 soda to neutralize the acidity of the cop- 

 per solution, and once with a dust spray 

 composed of about 30 pounds of lime, 15 



