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has not been definitely proven. As no winter spores have yet been 

 observed, it is believed that the threads of the fungus live over winter 

 in the affected dormant tubers, and from these the following- season make 

 their way back to the stalks and leaves. It is probable that the soft rot 

 of potatoes is mainly of bacterial origin. 



Colorado Potato Beetle (Doryphora decem-lineata, Say.) 



Treatment : Spray with Bordeaux, every two weeks, beginning- about 

 July ioth, and continuing well into September; plant the more resistant 

 varieties, and avoid wet soil, if possible. 



Early Blight (Macrosporium solani) : Attacks early potatoes. The 

 plants ripen prematurely, and the tubers are small. The affected leaves 

 become gradually discolored ; have many yellow areas, which are small 



Cucumber and Potato 

 Flea-beetle. 



Potato Stalk Weevil. Larva, beetle, and pupa — 



enlarged. 



and circular, except where several have run together ; and have a strong 

 tendency to curl. During the later stages of the disease the leaves 

 gradually become brown and shrivelled ; and the stems become yellowish- 



