THE POTATO TUBER 257 



In the United States, New York has led in potato production 

 for the past quarter century (Fig. 98). 



The leading States and yield per acre are as follows : 



Production in millions Yield per acre, 

 State of bushels, 1906-1910 1900-1909 



New York 43.5 88 



Michigan 30.0 88 



Pennsylvania 23.6 82 



Wisconsin 23.5 92 



Maine 22.8 180 



In the last few years Michigan, Wisconsin, Maine, and Minnesota 

 have been rapidly gaining in production and are now all close rivals 

 of New York. 



Origin and History of Potatoes. Several wild varieties of 

 potatoes are found growing throughout the Andes Mountains in 

 South America, and continuing northward through the mountains 

 of Mexico and into southwest Colorado. South American natives 

 have apparently cultivated the potato for many hundreds of years. 



Early explorers took potatoes back to Europe, but they did not 

 become an important food plant there until about the year 1750. Its 

 extensive culture developed first in Ireland, from which it got the 

 name " Irish Potato," where it was introduced about 1584, probably 

 from seed sent back by Sir Walter Ealeigh's expedition to America. 



Description of the Plant. Potatoes are closely related botani- 

 cally to several other important plants, as tobacco, the tomato, and 

 egg-plant. Wild potatoes bear only small tubers of poor quality, 

 but these have been improved by selection and cultivation. 



Potato Seeds. While potatoes frequently blossom under culti- 

 vation, they seldom bear seeds. This appears to be due to the pollen 

 having lost its ability to fertilize under cultivation. The seed balls 

 are borne on the tips of vines and resemble small green tomatoes, 

 each containing about 300 seeds (Fig. 99). If the seeds are 

 planted, they produce small tuber-bearing plants. If the tubers are 

 planted, a second year a plant of normal size is grown. While most 

 of the varieties grown from seed are of little value, yet occasionally 

 varieties of great value are originated in this way. 



The Potato Tuber. The potato tuber is not a root, but corre* 

 17 



