134 
Journal of Agricultural Research 
Vol. VIII, No. 4 
The averages of all plots receiving nitrogen agree closely, whether the 
nitrogen was applied singly or in combination with other fertilizers, as 
shown by Table VI. 
Table VI. —Average composition of oranges when fertilized with nitrogen alone and in 
combination 
Fertilizer. 
Specific 
gravity. 
Juice. 
Sugar. 
Acid. 
Nitrogen. 
Per cent. 
Per cent . 
Per cent. 
Per cent. 
Checks. 
0 . 01 
49.2 
9-36 
0. 92 
O. 089 
Nitrogen alone. 
.90 
47*0 
8.85 
*94 
. 121 
Nitrogen with other fertilizers. 
.90 
47 *o 
8. 84 
•95 
. II9 
It may be concluded, then, that nitrogen exercised a definite influence 
on the composition of the crop, whether applied with or without other 
fertilizers. 
The average composition with and without potash is shown in 
Table VII. 
Table VII. —Comparison of the averages of all plots receiving potash and those not 
receiving potash 
Fertilizer. 
Specific 
gravity. 
Juice. 
Sugar. 
Acid. 
Nitrogen. 
Per cent. 
Per cent. 
Per cent. 
Per cent. 
Check. 
0. 91 
49. 2 
9-36 
0. 92 
O. 089 
Potash. 
• 9 1 
48.5 
9. 02 
.94 
• 105 
Without potash. 
• 9 1 
47.6 
9. 12 
•93 
. 105 
These averages are somewhat lower than those of the plots receiving 
potash only. This, however, does not necessarily indicate that the 
percentages (of sugar, for example) have been increased by the use of 
potash alone as compared with potash in combination with other ferti¬ 
lizers, but rather that the depressing effect of nitrogen appears in the latter 
case. This is more clearly shown by contrasting the average of plot L, 
which received potash and nitrogen, with plot R, which is nearly adjacent 
and received potash alone. The average percentage of sugar in the fruit 
from plot L was 8.58, somewhat lower than that of the plots fertilized 
with nitrogen only, while R showed 9.03 per cent. 
On the whole, then, Table VII, when considered in conjunction with 
Table VI, lends but little support to the view that potash fertilizers mate¬ 
rially modify the composition of oranges. A careful study of the data 
in Tables II and III will likewise show but little effect from phosphate. 
It is only fair to state, however, that this soil is naturally well supplied 
with both potash and phosphate, and therefore conclusions should not be 
drawn with reference to the effects of potash and phosphate fertilizers 
on the composition of oranges generally. 
