The Anthracnose Disease of the Raspberry i8i 



The chemicals evidently do not penetrate far enough into the lesions to 

 kill the pathogene, or else they fail to remain on the plants for a sufficient 

 length of time to prevent the fungus from sporulating. Although the 

 iron sulfate did not injure the buds, it caused the canes to turn black, 

 giving the plants the appearance of having been burned over by fire; 

 but this caused no harmful effects to the plants. This blackening of the 

 canes was observed on the Columbian variety, and whether or not it 

 occurs on all varieties of the raspberry is not known. 



The yield of berries was recorded in only one experiment. On two 

 rows, with approximately sixty-six bushes each and with 44 per cent 

 of the canes diseased, there were estimated to be about 360 quarts more 

 per acre than on two check rows with 90 per cent of the canes diseased. 

 The treated plat had been sprayed with bordeaux and was separated 

 from the untreated plat by two rows. This is but an indication that 

 spraying is beneficial, and no adequate conclusions can be drawn from 

 so small an experiment. More data relating to the effect of diseased canes 

 on the yield of the fruit are needed, and until they are obtained no con- 

 clusive proofs can be furnished that spraying to combat the anthracnose 

 of the raspberry is a profitable practice. 



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