CHAPTER XIX 

 ROOTS AND TUBERS 



303. Value and importance. Irish potatoes are grown in every 

 state in the Union and furnish an important part of our food. 

 Sweet potatoes are grown principally in the cotton states and, 

 like Irish potatoes, are increasing in importance as a food crop. 

 In 1913 the United States produced 331,526,000 bushels of 

 Irish potatoes, valued at $227,903,000, and 59,057,000 bushels 

 of sweet potatoes, worth $42,884,000. Beets, turnips, carrots, 

 parsnips, and salsify are grown very generally in family and 

 market gardens. They add much to the food supply and help 

 to vary the diet. Stock beets and turnips are grown in the 

 Northern states for feeding cattle, sheep, and poultry. 



The Irish potato is a tuber (Fig. 1 10), or underground stem ; the 

 sweet potato, beet, parsnip, carrot, and salsify are enlarged roots. 



304. Soils adapted to roots and tubers. Root crops may be 

 successfully grown in a variety of soils and locations. The ideal 

 soil, except for the sweet potato, is a deep, loamy soil well 

 supplied with plant food but not too rich in nitrogen. The 

 sweet potato succeeds best in a sandy soil. All these crops 

 require a good supply of potash and phosphorus for the best 

 results, and the soil must be supplied with liberal amounts of 

 readily available plant food if a high quality and a satisfactory 

 yield are to be secured. Soil that has been in a good state of 

 tilth for some time previous is preferred. It is better to apply 

 barnyard manure the season preceding rather than immediately 



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