24 



C«^miERC lAL FERTILIZERS 



Purchases' 



For the year of this study (.1928 for all areas except Arkansas which 

 was for 1929), a majority of the growers in each of the areas purchased ferti- 

 lizers/ The proportion of growers buying fertilizer varied from 51.1 percent 

 in Michigan to 90.7 percent in North En.st, Pa. (table 1.) 



For the growers buying fertilizer, an average of 3^91 tons per farm 

 Y/as purchased. The quantity varied fr9ml.69 tons for the Michigan farms to 

 10.71 tons per farm for the growers about Girard, Pa. Most of the fertilizer 

 bought by the Michigan gro?/ers (83 percent) .^ was used on vineyards v/heroas 

 in Niagara County, N.Y., the interviev;od growers used most of their fertilizer 

 on other crops, only 6 percent being used on vineyards. 



About one half the tonnage and one half the value of all fertilizer 

 bought by the interviewed grape grov/ers , in all of the areas, represented 

 ready-mixed goods. The proportion v/as; highest in Pennsylvania where 60 per- 

 cent of the fertilizer 02p onso was for mixed goods, and lowest in Michigan, 

 where mixed goods represented only 20 percent of the total expense for ferti- 

 lizers-.. On the farms studied in Arkansas and in the Finger Lakes area of 

 Now York, more was spent for sodi^um nitrate than for mixed fertilizers. For 

 qll farms studied in all areas about one half as much Y/as spent for sodium 

 nitrate as for mixed goods ♦ 



In Michig:.n 71 percent of the expenditure for fertilizer v/as for 

 ammoni-um sulphate. Girard growers also used considerable quantitie-s of 

 ammonium sulphate. 'I^he average price ^paid in 1928 was $59.29 per ton v/hieh 

 was practically the same as the price :paid for sodium nitrate. Since sodiimi 

 nitrate carries about. 19 percent ammonia, and ammonium sulphate 24.3 percent 

 ammonia, 20 pounds of ammonia were purchased in sodium nitrate for $3.09 and 

 in ammonium sulphate for $2.44. 



For every dollar spent for fertilizer by the grape growers in all the 

 areas studied, 51 cents were spent for mixed fertilizers, 38 cents for straight 

 nitrogenous fertilizers, and 11 cents for all other kinds. 



For all the farms studied, about as many tons of sodium nitrate as of 

 acid phosphate wore bought. At the prices paid by these grov/ers in 1928, 20 

 pounds of phosphoric acid cost on the average $1.33^ Only four farmers ¥ought 

 muriate of potash. At $46.25 per ton, 20 pounds of potash cost $0.92. 



Ready -mixed fertilizers are sold by analysis. The first number of the 

 analysis refers to the percentage of nitrogen or ammonia carried in the ferti- 

 lizer, the second number to the percentage of available phosphoric acid, and 

 the last number to the percentage of potash. The sum of the percentage fig- 

 ^ores of a given analysis represents the units of plant food in the fertilizer. 

 Thus, a 5-8-8 fertilizer contains 5 4- 8 + 8, or, 21 units of plant food. In 

 1928, nitrogen was given in terms of ammonia in the States v/here this study 

 was made. State retaliations as of January 1, 1932 for all but six southern 

 States require that the analysis express nitrogen as nitrogen rather' than 

 ammonia. 



