May, 1929] Potato Production Costs in New Hampshire 15 



TABLE XI. 

 Influence of Source of Seed on Yield, Cost and Labor, 



Because of the smaller yield by the two applications method in the 

 rest of the state, cost per bushel was considerably higher. 



Amount of Fertilizer 



The total amount of fertilizer had a much more important 

 influence on yield than did the method of application. Yet in a very 

 dry year increasing- amounts of fertilizer may show little or no 

 increases in yield, and the increases may barely pay for the extra 

 fertilizer, (Table XIII.) If suitable land is limited in quantity 

 it may be more desirable to obtain higher yields by using- the larger 

 amounts of fertilizer on the same area. If, however, suitable land 

 is available, results would warrant using more land and putting the 

 extra fertilizer on the increased area. 



Amounts of fertilizer much above 1,500 pounds did not pro- 

 duce the same increases in yield for each increase in fertilizer that 

 were obtained from amounts under 1,500 pounds. 



The total amount of manure applied was considerably more 

 than the amounts shown. (Table XIII,) Only that portion 

 thought to be used by the crop was charged to it. It was assumed 

 that 40, 30, 20, and 10 per cent, of the manure was received respec- 

 tively by the first, second, third and fourth crops after application. 

 On lighter soils a 50, 30 and 20 per cent, distribution was used. 



Only two farms failed to use manure in Coos and Grafton 

 Counties, These two farms did not have it to use. In the rest of 

 the state few farms failed to use manure where it was available. 

 One larger grower without stock attempts to replace organic matter 

 with a green manure crop on at least part of his area. 



