EXPERIMENT STATION BULLETINS. 307 



SCHEDULE OP COMMERCIAL PRICES. 



The following prices per pound for fertilizing materials may be used in estimating 

 the commercial value: 



Nitrogen in nitrates $0 13 



Nitrogen in ammonia salts 14 



Organic nitrogen in meat, blood, etc 14 



Organic nitrogen in fine bone and tankage 13 y.. 



Organic nitrogen in medium bone and tankage 1<> 



Organic nitrogen in coarse bone and tankage 8 



Phosphoric acid, available 4 ' ... 



Phosphoric acid, insoluble, in fine bone and tankage 4 



Phosphoric acid, insoluble, medium bone and tankage •'!' '. 



Potash as muriate 4y 3 



Potash as sulphate and in wood ashes 5 



COMMERCIAL VALUE AND AGRICULTURAL VALUE. 



The commercial value and the agricultural value are not identical. The commercial 

 value merely represents the cost of the material to make the fertilizer, if any one 

 should attempt to make his own. The agricultural value or the benefit from the use 

 of such fertilizer will depend upon a variety of conditions, such as the kind of soil, the 

 crop, the season, the tillage, time of application, etc., etc. Let no one suppose that 

 the estimate of the commercial value is a guarantee of a corresponding profit by its use 

 on the farm. It may serve, however, as a basis of comparison between different brands 

 of fertilizers. The reliable test of the value is determined by its use on a given soil 

 and crop — worth more than all theoretical discussions and deductions. Yet there are 

 certain general considerations which go to show the probable benefit of any fertilizing 

 element when used on a certain kind of soil and crop, which will be of some benefit in 

 selecting a fertilizer. 



SELECTING SPECIMENS OF FERTILIZERS FOR ANALYSIS FOR THE BULLETIN. 



The law requires the manufacturer or dealer to deposit a specimen of each fertilizer 

 with the secretary of the Board, but such specimens are never used for analysis unless 

 it is impossible to obtain specimens from the material exposed for sale in the open 

 market. The object is to deal with the same material that the farmer buys for himself. 

 In this way any collusion by which a richer fertilizer is analyzed than will be found 

 in the fertilizer offered for sale in the open market, is prevented. 



As the fertilizers arrive at somewhat uncertain periods and are distributed over a 

 wide extent of territory, the gathering of the specimens requires much travel and time 

 in order to cover the whole area of fertilizer consumption. 



The following stations and names of the dealers give some idea of the thoroughness 

 with which this work is done. It is not feasible to visit every dealer, but the aim is 

 to go over the more important districts for the specimens. 



Some of the parties visited on the fertilizer collection from May 6 to June 15. Nanus 

 of individuals and firms, arranged in alphabetical order with reference to counties. 



Bay Con it la. 

 Bay City. 



Mosher Hardware Co. 

 Rechlin Hardware Co. 

 McDonald Hardware Co. 

 Jennison Hardware Co. 

 P. C. Goddene. 

 Boutelle Bros. 

 Presley and Layer. 

 P. C. Bialy. 

 Mitchell and Co. 

 W. IT. Fa v. 



