May 14 ,1917 
Soil Nitrogen and Nutrition of Citrus Plants 
201 
effect of temperature and also the effect of large and small quantities of 
dried blood upon the nitrifying power of these soils, samples of soil were 
collected from each of eight plots, as shown in Table X. After thoroughly 
mixing and removing gravel and roots, etc., six portions, each equivalent 
to 1 kgm. of dry soil, were weighed out from each soil. 
Table X .—Nitrifying power of soils in incubator at 28 0 C. and in field at i?° to 20° C. 
March 2> iqi$ 
[Results expressed as milligrams of nitrogen per 100 gm. of soil] 
Incubation 
Material 
Constitu- 
Plot 
Plot 
Plot 
Plot 
Plot 
Plot 
Plot 
Plot 
period. 
added. 
ent. 
B. 
T. 
C. 
S. 
F. 
O. 
E. 
U. 
At beginning of 
/Ammonia. 
[Nitrates... 
0.39 
0.60 
0.32 
0.88 
0. 50 
0.67 
0.53 
0.53 
experiment. 
. 18 
. 18 
. 22 
*36 
*57 
•43 
.29 
•25 
No nitrogen 
added. 
—do. 
Ammonia. 
. 60 
. 62 
.60 
.78 
•53 
.73 
.42 
.84 
Nitrates... 
.48 
.81 
.46 
•95 
x. x6 
1*34 
.46 
.98 
0.1 per cent 
Ammonia. 
1.82 
.18 
x.40 
.70 
.73 
.00 
.00 
.20 
After 14 days’ in- 
dried blood 
cubation at 28° 
added. 
C. 
_do. 
Nitrates... 
6.72 
84.70 
6.09 
89.04 
6.26 
74.20 
7.27 
52.22 
7.42 
77 - 56 
6.93 
57*94 
7.00 
74*20 
7.60 
56.28 
1.0 per cent 
Ammonia 
dried blood 
added. 
_do. 
Nitrates... 
.00 
.91 
.00 
26. XX 
14.00 
26.65 
XX. 62 
2 X. 21 
No nitrogen 
Ammonia. 
• 74 
1.02 
.60 
X.04 
. 60 
.88 
•74 
•74 
... .do. 
Nitrates... 
• 53 
.88 
.33 
1*37 
1.58 
1*93 
•53 
1.09 
0.1 per cent 
Ammonia. 
1.68 
• 18 
. 14 
.14 
.28 
.14 
.14 
.14 
After 38 days’ in¬ 
dried blood ; 
cubation at 38° 
added. 
c. 
.... do. 
Nitrates. •. 
6.65 
84.56 
7.08 
86. 24 
7 - 43 
78.54 
7.07 
51* 34 
6. 72 
% 07 
7 « 70 
7 . Aft 
1,0 per cent 
Ammonia. 
58.94 
51-80 
63* 56 
40* 14 
dried blood 
added. 
.do. 
Nitrates... 
.00 
4.90 
.00 
33*30 
Lost. 
28.44 
30.87 
24.99 
49*59 
No nitrogen 
added. 
— do.. 
Ammonia. 
1.02 
Lost. 
•74 
• 74 
• 74 
.60 
.60 
Nitrates... 
• 7 i 
1.12 
.46 
1 * 54 
x* 54 
1.54 
•49 
.83 
After 28 days’ in 
0.1 per cent 
Ammonia. 
I. 71 
a 3.34 
.28 
Ox. 30 
.00 
.56' 
.28 
.14 
dried blood 
the field at 17- 
added. ■ 
20° C, 
... ,do. 
Nitrates... 
6-33 
61.04 
r. Oft 
8.26 
71.96 
7.43 
« 43*58 
6.86 
33 * 60 
6.86 
26.60 
8. 22 
44.10 
8.68 
28.70 
1.0 per cent 
dried blood 
Ammonia. 
®36- 30 
added. 
Nitrates... 
3 ‘S 6 
28- 00 
• T ft 
30.80 
30.84 
33.60 
29.08 
37.16 
No nitrogen 
added. 
_do. 
Ammonia. 
x.06 
.84 
•56 
.84 
.84 
x. 08 
.68 
.68 
Nitrates... 
1. 20 
2. 10 
x.06 
2.80 
3.94 
3 * 50 
X. 20 
2.80 
0.1 per cent 
Ammonia. 
.06 
1.06 
•56 
.28 
.28 
- .18 
- .28 
— . 44 
After 56 days’ in¬ 
dried blood 
cubation at 28° 
added. 
C. 
_do. 
Nitrates... 
9. 72 
9.94 
9.99 
XO. 20 
11.76 
10.08 
9*44 
9.94 
1.0 per cent 
dried blood 
Ammonia. 
63.90 
64.96 
65.24 
49*76 
55*i6 
34*60 
50.40 
39* 13 
1VV* uiuuu 
added. 
.do. 
Nitrates... 
- *47 
24.78 
— . 22 
43 . X2 
28. 70 
56. X4 
37. x6 
47*88 
No nitrogen 
added. 
Ammonia. 
.84 
. 70 
.84 
x. 12 
.84 
.98 
•94 
.84 
_do. 
Nitrates... 
1. 24 
1.68 
x. 26 
2. 24 
1.96 
2.35 
.98 
1.90 
After 56 days’ in- , 
cubation in the 
0.1 per cent 
dried blood 
added. 
... .do.. ...... 
Ammonia. 
. 24 
• 56 
.42 
.14 
- .28 
.14 
•33 
. xo 
field at 17-20® 
Nitrates... 
9« 22 
O* 2A 
O. O A 
8.68 
46.48 
(V O A 
O. n*r 
8.66 
50.30 
C. 
1.0 per cent 
dried blood 
Ammonia. 
75- 22 
y* 
5 5 - 98 
y* y4 
84.22 
y* 
41.72 
y* *1 
38.78 
41.72 
added. 
After 90 days’ in¬ 
—do. 
Nitrates... 
3-04 
48 92 
1.26 
39 * 76 
38.64 
46*93 
34*02 
54* 10 
No nitrogen 
Ammonia. 
■32 
■77 
•35 
.93 
•S 3 
• 71 
•49 
•45 
cubation at 28° 
added 
C. 
-do. 
Nitrates... 
• 95 
I. 79 
1.30 
3 * 19 
2.92 
5* 15 
I* 51 
4*03 
After 90 days' in 
No nitrogen 
Ammonia 
.46 
• 77 
.42 
i* 13 
.56 
*71 
•56 
*53 
the field at 17- 
added. 
20® C. 
— do.. 
Nitrates... 
1.16 
1. 72 
1*51 
3 * 77 
2.85 
3 * 96 
x. 65 
3*05 
a Ammonia in the control not subtracted. 
