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found by aid of the microscope. When holes have 

 been made by grubs, wireworms frequently creep into 

 them, and then they often feed by grazing on the 

 flesh of the potato instead of boring into it. 



Injury by Frost. 



Frost affects the potato injuriously at several periods. 

 Spring frosts, or, worse still, summer frosts, cause 

 injury by destroying the leaves and haulm of young 

 plants, sometimes cutting them so severely that they 

 are entirely destroyed ; at others causing only a 

 temporary check. When grown on a large scale, 

 little can be done to prevent injury. Moulding-up 

 prevents the frost aifecting them so far down the 

 stem, but the crop is not always sufficiently matured 

 to be moulded up. If a frost is expected immediately, 

 care should be taken in moulding, as the bruising 

 to which the tops are subjected renders them more 

 liable to injury. Moulding-up should not be done late 

 in the day if a frost is expected at night. When 

 grown in gardens a covering of straw is commonly 

 used to keep off the frost, and in all but the most 

 severe cases proves effectual. 



Freezing in the ground in autumn is by no means 

 rare, and points to the necessity of getting the crop 

 dug as soon as it is fit. The advantage of deep 

 moulding is realised during these autumn frosts, as 

 those exposed are more readily injured than are those 

 deep in the soil. Those frozen should be kept apart 

 from the sound ones, as they cause fermentation in the 



