The Irish Potato Crop 245 



remain cool even into the warm weather of the spring, 



and there will be Httle tendency to sprout. 



There are two forms of fungus disease 



Diseases and that affect the potato crop so far as the tops 



A^^^^t- * are concerned, and another form that 

 AfEect the ' 



Potato affects the tubers only. For the first two 



diseases, the early and late bUght, spraying 



with a good fungicide is essential to the success of the crop. 



The foliage of the potato is also subject to the attacks 

 of the Colorado potato beetle, and if preventive means 

 are not used, this insect in most parts of the coimtry will 

 totally destroy the crop in some seasons. The fungus 

 disease that affects the tubers only, the scab, demands 

 special treatment of the tubers before planting, of which 

 later. 



The most generally used preventive of the bhghts is the 

 mixture known as the Bordeaux mixture. There are sev- 

 eral formulas for making this, but the one we have most 

 generally used for the potato crop is as follows: Dissolve 

 five pounds of copper sulphate in a cask with twenty-five 

 gallons of water. In another cask slake five pounds of 

 fresh lime as for whitewash, and after slaking add water 

 enough to make this twenty-five gallons. Strain these 

 slowly into a third cask, stirring all the time. The mix- 

 ture is then ready for use. The spraying is done with a 

 spraying pump, of which there are numerous kinds, large 

 and small. One of the best is a cask with a pump on a 

 four-wheeled wagon with four nozzles arranged to spray 

 four rows at once. Where the crop is grown on a smaller 

 scale the spraying can be done with a knapsack-sprayer 

 carried on the shoulders of the operator. 



