36 SECOND THOUSAND QUESTIONS IN AGRICULTURE 



end is cut off. If this is the trouble, don't plant any potatoes close to 

 the place you had them last year, till several seasons have starved the 

 fungus. Early Rose and Burbanks brought from disease-free sections 

 are the standard. If black circles on inside show in the seed potatoes, 

 don't plant them, for they will infect the soil. Strands of the fungus 

 close the water tubes of the plant and cause premature wilting. Never 

 plant very small potatoes that's what makes them "run out." 



Potato Worms. 



/ send sample of potatoes grown on subirrigated land. They are 

 good size and perfect flavor, but many have the defect of skin as shown 

 by the sample sent. I am told by some it is due to too much moisture. 



It is not merely moisture ; your potatoes were attacked in the ground 

 by potato scab and during or after harvesting received the eggs of the 

 tuber moth. The flat blotches are the scab, the excavations and tunnel- 

 ing near the surface are the work of the potato worm. Use the ground for 

 hay or grain and put your potatoes on new ground, after soaking the 

 seed in formalin (1 pint to 30 gallons of water) for an hour and a half, 

 just before planting. To escape the moth, throw earth toward the row 

 a little at the last cultivation but do not "hill up" too much. Never 

 allow the tubers to be exposed after digging. The moth will also attack 

 them in the sack ; therefore sacks should be well covered with straw or 

 litter or placed at once in dark storage. 



Potatoes Scabby and Hollow. 



My land is new, broke out of old stock pasture, and very rich. Some 

 of my potatoes are scabby and others hollow-hearted. 



Treatment for scab is given in Part II, Vol. 1. Very rich soils are 

 more addicted to the production of scabby potatoes than land not rich 

 in humus. The cause of hollow-heart in potatoes is overrichness of the 

 soil and the plants given too much room to develop. To prevent hollow- 

 heart in potatoes where the soil is very rich, they should be planted 

 closer together. 



Sweet Potatoes in Heavy Soil. 



Is it practicable to grow sweet potatoes under irrigation on heavy 

 clay soil containing considerable lime, provided organic matter were 

 worked in? 



You might do well enough for home use with sweet potatoes on such 

 soil after you had lightened it up enough as you propose, but such soil 

 is not naturally adapted to make a handsome product, as is required in 

 commercial production. 



Gophers and Seed Potatoes. 



What is the best rvay to prevent gophers from attacking potatoes 

 when planted? 



