REPORT ON INSPECTION WORK. 



SOME FACTS ABOUT COMMERCIAL FERTI- 

 LIZERS IN NEW YORK STATE* 



L. L. VAN SLYKE. 



SUMMARY 



I. COMPOSITION OF FERTILIZERS AND COST OF PLANT-FOOD 



CONSTITUENTS. 



(i) In the purchase of complete fertilizers, plant-food constituents 

 cost least in high-grade mixtures and most in low-grade. (2) The 

 tendency among farmers at the present time appears to be in the 

 direction of purchasing more high-grade mixtures. (3) In complete 

 fertilizers as well as in other mixtures and unmixed materials, the 

 variation in selling price is often wholly out of proportion to the 

 amount of plant-food present. (4) Nitrogen costs least in nitrate of 

 soda ; in organic materials it costs least in dried blood, tankage and 

 fish scrap. (5) Phosphoric acid in quickly available form costs least 

 in the form of acid phosphate ; in organic materials it costs least in 

 the form of tankage. (6) Potash costs least in muriate of potash. 

 (7) Plant-foods can be purchased generally in unmixed materials at 

 less cost than in mixtures. (7) In dried commercial sheep manure 

 plant-food costs more than in any other form examined. 



II. RELATION OF GUARANTEED TO ACTUAL COMPOSITION 



IN FERTILIZERS. 



(1) In the case of each constituent of complete fertilizers, the num- 

 ber of samples showing results above the guaranteed statement of 

 composition is much larger than the number below. (2) The largest 

 number below guaranty is in case of nitrogen (166 samples), followed 

 by potash (151 samples), while the smallest number (112) below is 

 in case of phosphoric acid. (3) Balancing all the cases of excess and 

 deficiency in the 614 samples of complete fertilizers, we find that 

 there is an average excess of 0.08 per ct. of nitrogen, 0.44 per ct. of 

 available phosphoric acid and 0.34 per ct. of potash. (4) In the case 

 of fertilizer materials and mixtures other than complete fertilizers, 

 the average percentage found is above that guaranteed in all cases 

 excepting fish scrap and calcium (lime) carbonate. (5) In such 



* Reprint of Bulletin No. 392, December; for Popular Edition see p. 959. 



[649] 



