THE POTATO 81 



presence. When disease is present, it can be carried 

 from a diseased potato to a healthy one by contact 

 in the bin, in the sack or in a planter. The knife 

 used in cutting seed pieces is capable of spreading 

 a disease throughout an entire lot of seed, and the 

 "picker "on a picker planter may do the same 

 thing. Disinfecting potatoes, as indicated in the 

 chapter on diseases, is a good practice for skin 

 diseases, but does not kill internal germ disease. 



In southern Idaho potatoes are planted from 

 May 1st to July 1st. Some early potatoes are 

 planted as soon as April 1st. If these escape the 

 late frosts they make big money, generally selling 

 locally at from three to five cents a pound. If the 

 frost catches them the ground may be planted to a 

 later crop, so that some gamble on a few early 

 potatoes to the extent of the price of seed and labor. 

 There is always a possibility of a killing frost dur- 

 ing the first two weeks of April. 



From May 10th to June 10th is generally con- 

 sidered the best time to plant the main crop of late 

 potatoes in the inter-mountain West. 



With the horse planters a furrow two to four 

 inches deep is opened by a pair of disks, and a ridge 

 about two inches higher than the level of the field 

 is turned up, putting the seed piece under about 

 four to six inches of earth. 



The amount of seed used by different potato 

 growers varies from 600 to 3,000 pounds per acre. 

 The growers who get the biggest yields plant the 

 most seed. The largest crop ever grown in the 

 country was with whole seed, using nearly 3,000 

 pounds per acre. Good yields are secured by using 

 seed cut in two to four ounce pieces and having 

 one to two eyes. Commercial seed potatoes weigh 

 from two to ten ounces. The small seed is not cut 



