FERTILIZER NOTES I 5 



phoric acid as nitrogen and from two to four times as much 

 phosphoric acid as potash. The persistent use of the aver- 

 age fertilizer must then result in an accumulation of useless 

 phosphoric acid in the soil, accompanied by an exhaustion of 

 the soil's available nitrogen and potash, and in diminishing 

 crops. On most of our New Hampshire soils such a fertilizer 

 will need to be employed in conjunction with barn-yard ma- 

 nure, to be economical, since the manure will supply the nitro- 

 gen and potash, which the fertilizer lacks. 



Thirty-one brands are not warranted to contain more than 

 1.5 per cent, of nitrogen, and have been prepared and placed 

 on the market, because of the demand for cheap fertilizers. 

 Nitrogen is the most expensive ingredient of a fertilizer, cost- 

 ing about three times as much as either potash or available 

 phosphoric acid, and is invariably the constituent to be lowered 

 in a mixed fertilizer in order to reduce the price. 



It is only in exceptional soils, such as new ground or land 

 previously heavily manured, that crops will receive nitrogen 

 sufficient for successful growth when such low grade fertilizers 

 are applied. Several letters have been received during the 

 past year, testifying to the disappointment liable to be incurred 

 by the users of fertilizers containing small proportions of active 

 nitrogen. 



The buyers of ready-mixed fertilizers should bear in mind 

 that it is as important that they study the composition of the 

 fertilizers as that the station chemist does. In the latter case it 

 is essential to know merely that the analyses and guarantees 

 are alike, while in the former case it is necessary to know that 

 the composition is suitable for the uses intended. The name 

 of a brand is no indication that it is suitable for a special crop. 

 Hardly two manufacturers agree in their special fertilizers 

 for corn and similar crops, while some companies issue not 

 less than three distinct mixtures each for such a crop as pota- 

 toes. 



It should also be remembered that there is no "best fertil- 

 izer" made, but each farmer may by careful observation de- 

 termine those brands which serve his purpose best, and he 

 should know them by their composition, instead of simply by 

 name or price. A comparison of the constituents of any ten 



