EXPEEIMENTAL WORK WITH RAW ROCK PHOSPHATE. 



55 



1892. Six plots received no fertilizer treatments whatever. The 

 remaining 30 plots received 10 different fertilizer treatments, the 

 same treatment being applied to three plots in each case. The aver- 

 age annual results obtained from each fertilizer treatment are given 

 in Table XXIX. ■ 



Table XXIX. 



-Results of nine years of field icork in the growing of various 

 crops {18SG-1S94). 





AppK- 



cation, 



per 



a<;re. 



Yield per acre (average of 3 plots). 



Fertilizer. 



1886 



1887 



18881 



1889 



18901 



1891' 



18921 



1893 



1894 





Oats. 



Oats. 



Hay. 



Fal- 

 low. 



Peas. 



Oats. 



Peas. 



Com. 2 



Com.2 





Lbs. 



Lbs. 

 3,664 



Lbs. 

 2,000 



3,400 

 2,566 



3,100 



3,074 

 2,400 

 2,100 



2,634 

 2,834 



3,500 



3,834 

 2,700 



Lbs. 

 2,566 



2, 434 



2,800 



2,566 



4,010 

 1,634 

 2,166 



2,066 

 2,166 



1,766 



2,374 

 2,234 





Lbs. 

 1,406 



1,850 

 1,922 



1,762 



2,644 



1,618 

 1,774 



1,978 

 1,738 



1,694 



1,778 

 1,422 



Lbs. 

 1,892 



2,332 



2,466 



1,936 



3,288 

 2,068 

 2,666 



2,668 

 2,496 



2,700 



2,666 

 2,000 



Lbs. 

 1,216 



1,124 

 1,072 



860 



1,976 



1,180 



668 



736 

 848 



1,092 



1,084 

 1,180 



Lbs. 

 395 



1,415 

 1,326 



1,076 



2,931 

 366 

 576 



1,486 

 942 



967 



2,046 

 905 



Lbs. 

 749 





400 



1 





Potassium chloride 



100 ^5,900 

 200 J 

 360 1 



100 ^5,420 

 200 1 



2,926 











3 038 







Ground South Carolina rock.. 



300 



100 



200 



40,000 



5,052 



5,266 

 3,968 

 4,512 



|4,906 

 4, 732 



•5, 640 



2 631 



Ammonium sulphate 







3,562 



X'n fp.rt.ilizfir ' 



978 



Dissolved bone black 



400 

 400 

 100 

 200 

 50 

 60 

 300 

 100 

 120 



1,280 



Do 





Potassium chloride 



2,532 







Pntn=;=;iurn nhlnride 



1,982 





Dissolved bone black 





Potassium chloride 



2,598 







Dissolved bone black 



400 tl 



150 1^6,034 



180 J 







3,427 



Ammnninm sulphate 









Ammonium sulphate 



1,879 





1 







1 No fertiUzers. 



* Air dried. 



In this experiment the plots treated with stable manure gave on 

 the whole better results than any of the other plots. The plots re- 

 ceiving heavy applications of dissolved bone black in combination 

 with potash and nitrogen carriers came next, followed by those 

 treated with a mixture of bone meal, potash, and nitrogen. The 

 plots treated with ground raw rock phosphate gave a lower average 

 increase than the other phosphates, but produced in all but two 

 instances a distinct gain over the plots fertilized with potash and 

 nitrogen carriers alone. 



While the applications of dissolved bone black (300 and 400 

 pounds per acre) employed in this experiment are considered com- 

 paratively heavy for such a soluble phosphate, an application of 

 300 pounds of ground raw rock is a light application for such a 

 relatively insoluble material. Moreover, in describing this experi- 

 ment there is nothing to indicate that the soil was well supplied with 



