RICE EXPERIMENTS IN CALIFORNIA. 23 
As shown in Table 18 all except two of the fertilizers applied have 
resulted in increased average yields, ranging from 21 pounds per 
acre for acid phosphate to 879 pounds per acre for manure. The 
average increase in annual yield in the 3-year period from applying 
manure was 879 pounds: sulphate of ammonia, 651 pounds; dried 
blood, 646 pounds; and cottonseed meal, 583 pounds per acre. The 
application of lime resulted in a reduced yield, as did the use of acid 
phosphate and sulphate of potash in combination. 
The average yields obtained in the fertilizer experiments with 
rice at the Biggs Rice Field Station from 1914 to 1916, inclusive, are 
shown graphically in Figure 10. 
The average price received for rough rice during the 3-year period 
from 1914 to 1916 was $1.90 per 100 pounds. By deducting the 
cost per acre of the fertilizers and not including any charge for 
applying them, the increases show an average profit of $12.70 per 
PEPT/L/ZEP PEPAOPE >"*"> ^ *™£ (POC/A/OSj 
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£*/£D Eiooo - BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBI 4,255 
cottoa/seeo meal 280 ■BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB 4,/ 32 
AC/£> PPOSPPATE (j50 ^^^^^^^^^M^^^^^^^^^^^^^^^^^^^M ?9 7J 
SCLPHATE OEAMMO/V/A \/ OO ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^™ ^ 
SULPHATE OF POTASH [ /OO ^^^^^^^^^^^^^^^^^^^^^^^^^^^^HM TQPO 
Sl/lPWAT£C£AMOA/A \ / O O ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ^ 
AC/O P//OSPPAT£ f 35Q „„ 
sulphate crporAS//\ /oo BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBHBm^J 
SULPHATE O£AMA/0/Y/A\/OO _^_______^^_^^^^_^_^^_^^___ 
swlphate o/pporAS// /oo BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB 3,33 z 
SO/P/UAf A//rffAr£ /oo 
AC/O PZ/OSPPAPS 350 
C//£C/r o 
/1C/0 PPOSPPATE [35O 
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Fig. 10.— Average acre yields of Wataribune rice obtained in the fertilizer experiments at the Biggs Rice 
I feld Station in the 3-year period from 1914 to 1916, inclusive. 
acre resulting from the application of manure, $9.09 per acre from 
sulphate of ammonia, $8.16 from dried blood, and $5.85 per acre 
from cottonseed meal. The fertilizers used, with the exception of 
manure and lime, could be applied at seeding time with a fertilizer 
attachment without appreciable cost. 
Other fertilizers and combinations have increased yields, but the 
increase has not been enough to cover the cost of the fertilizers. 
For example, sulphate of ammonia and sulphate of potash when 
applied in combination increased the average yield 311 pounds per 
acre, but the cost per acre of the fertilizer was more than the value 
of the additional crop. 
Manure, sulphate of ammonia, dried blood, and cottonseed meal 
have improved the color and vigor as well as increased the yield of 
the rice crop at the Biggs Rice Field Station during the 3-year period 
from 1914 to 1916, the net profit ranging from $5.85 per acre for 
cottonseed meal to $12.70 per acre for manure 
