Vegetables with Edible Tubers or Roots 253 



crop. It will, however, be found difficult to keep the vines 

 healthy and the field free from weeds. It is also necessary 

 to have the field well prepared as to drainage, for while 

 potatoes like a moist soil they cannot stand a soggy one. 

 The second crop is simply intended for home use and 

 for local markets. It is well worth the time and trouble 

 to raise this fall crop when one has to pay $1.50 to $2 a 

 bushel at retail for potatoes grown in the North. This 

 second crop is sometimes used to supply seed tubers for 

 the spring. 



Diseases of potatoes. 



Scab is often carried by the seed potatoes. It may be 

 lessened or prevented by treating the seed with a dilute 

 solution of corrosive sublimate or of formalin. 



Early blight is caused by a fungus which spreads on the 

 leaves in ring-shaped areas, and decreases the yield. It 

 may be prevented by repeated spraying with bordeaux 

 mixture. 



Late blight destroys the leaves and rots the tubers. 

 It may be prevented or checked by thorough spraying with 

 bordeaux mixture. 



Rhizoctonia (Corticium) causes rotting of the base of 

 the stem and resetting. It is often carried by the seed 

 potatoes, and the remedy is to plant healthy seed. 



Bacterial blight causes the leaves and stems to wilt 

 and is contagious. 



Bulletins. 



Growing Irish Potatoes, Fla. Exp. Sta. Bulletin 82, 1905. 

 The Cultivation of Potatoes, Va. Exp. Sta. Bulletin 174, 1907. 



