Success in growing potatoes depends first of all on the planting of tubers 

 produced by plants free from mosaic diseases. Such "seed tubers" can be 

 produced best in regions like northern Maine. There the cool summers 

 favor a good growth of the plants and the crop matures at a time most 

 suitable for immediate winter storage. Also aphids are less abundant than 

 in warmer sections farther south so the spread of the disease in potato 

 fields is less. 



To control and eliminate these tuber-borne diseases the grower rigidly 

 "rogues" plants showing signs of disease. He may also combat the aphids 

 by sprays of nicotine solutions and by destroying all rose bushes in the im- 

 mediate vicinity for it is upon the roses that certain of the potato aphids feed 

 in early spring before the potato plants are available to them. 



Many potato growers have rarely or even never seen fruits on potato 

 plants. The plant is propagated by tubers, and it is the tubers that are u :ed 

 for food. The fruit is only of importance in the breeding for new varieties. 



In cool-season areas like northern Maine all varieties usually bloom in 

 profusion quite as shown in the above view. In warm-season areas they 

 are decidedly non-blooming. But most varieties have imperfect flowers that 

 yield very little or no viable pollen. Thus in a field of Irish Cobbler, a 

 clonal variety, there is no chance for ]iii]linati<>n and tlie plants are fruit- 

 less. When there is proper cross-pollination with one of the few perfect- 

 flowered varieties then "seed balls" will be produced. If the potato were 

 grown for its fruit, interplanting to provide for pollination would need to 

 be considered as in certain clonal varieties of strawl)erries and grapes. 



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