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EXPERIMENTAL WORK WITH RAW ROCK PHOSPHATE. 5D 
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 X XIX. 
“TABLE XXIX.—Results of nine years of field work in the growing FE various 
crops (1886-1894). 
Yield per acre (average of 3 plots). 
Appli- | ae 
qrartilivor! ea 1886 1887 | 18881} 1889 | 18901 | 18911] 18921] 1893 | 1894 
acre 
Oats. | Oats. | Hay. Hee Peas. | Oats. | Peas. | Corn.2} Corn.2 
Lbs. Lbs. | Lbs. | Lbs. Lbs. |= Boss \obbss | ei ossalael ps 
IN@ Ta at AS cre oad See Be | aa 3,664 | 2,000 | 2,566 |....... 1,406 | 1,892 | 1,216 395 749 
Dissolved bone back......... 400 
Potassium chloride..........- 100 |75,900 | 3,400 | 2,434 |....... 1,850 | 2,332 | 1,124 | 1,415 | 2,926 
Ammonium sulphate......... 200 | 
Ground bones - 622 tise 360 
Potassium chloride........... 100 |-5, 420 | 2,566 | 2,800 |....... 1,922 | 2,466 | 1,072 | 1,326 | 3,038 
Ammonium sulphate.. ae 200 | 
Ground South Carolina rock.- 300 
Potassium chloride..........- 100 |}5,052 } 3,100 | 2,566 |....... 1,762 | 1,936 860 | 1,076 | 2,631 
Ammonium sulphate.. ee? 200 
Stableimanuren: 5.2.5.2 .05.: 40,000 | 5, 266 | 3,074 | 4,010 |_.....- 2,644 | 3,288 | 1,976 | 2,931 | 3,562 
INawfertilizens esse [ne ele 35968") 25400r; 1 634 ee eee 1,618 | 2,068! 1,180 | 366 978 
coed bone black........- 400 | 4,512 | 2,100 | 2,166 |....... 1,774 | 2,666 668 576 1, 280 
OBee attete cise cicen sine cet 400 |\, eB 
Egueastvic Guilgu@l lellnn 100 , 906 | 2,634 | 2,066 |....... 1,978 | 2,668 736 | 1,486 | 2,532 
Dissolved bone black......... 200 
Potassium chloride........... 50) |-4, 732 | 2; 834 | 2,166.|....... 1,738 | 2,496 848 942] 1,982 
Ammonium sulphate......... 60 
Dissolved bone black......... 300 
Potassium chloride........... 100 |+5, 640 | 3,500 | 1, 766 |....... 1,694 | 2,700 | 1,092 967 | 2,598 
Ammonium sulphate......... 120 | 
Dissolved bone black......... 400 | | 
Potassium chloride........... 150 1)767034: | 3,884 | 25374 |...-28. 1,778 | 2,666 | 1,084 | 2,046 | 3,427 
apap eee eae 180 | 
otassium chloride..-........ LOORIN e = ‘ = 
Ammonium sulphate..-...... 200 My HOON P25 7005 | 222340 aaa sane 1,422 | 2,000 | 1,180 905 | 1,879 
1 No fertilizers. 2 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 (800 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 
