CHAPTER VL 



MANURES AND FERTILIZERS 



By Daniel Dean 



The supply of plant-food elements present in soils will 

 produce potato crops of varying size according to the 

 climate, the original natural fertility of the soil-type and 

 the degree to which it has been reduced or improved in 

 condition since bringing under cultivation. Manures and 

 fertilizers are used to add plant-food in forms so easily and 

 quickly available that the crop will be able to take up 

 and use more than it could without them. On account 

 of its tender nature, compared with other farm crops, the 

 potato responds well to the use of fertilizers. Manures 

 and fertilizers are used wherever the increased yield brings 

 enough in the market returns to meet the additional cost 

 and leave a profit. For these reasons, the use of fertilizers 

 is more or less localized in the particular sections where 

 their use is most profitable. For example, the cool and 

 moist climate of the Aroostook region of Maine is very fa- 

 vorable to the production of large yields of potatoes to the 

 acre. In spite of the great natural fertility of the soils, 

 these fertilizers are used to the extent of over 1900 pounds 

 to the acre on the average at a cost of over $30, because 

 the practice pays. The great trucking region which 

 supplies city markets from April till autumn and extends 

 along the Atlantic coast from Florida to Long Island is 

 nearly all made up of sandj^ soils of low natural fertility. 

 I 113 



