20 
standpoint. 
SOILS OF THE TRUCKEE-CARSON IRRIGATION PROJECT. 
The results are all expressed in Table I as parts 
nitrogen per million of the solution. 
Ny 
: 
S 
= 
: 
S 
~~ 
= 
S 
S 
N 
N 
© 
S 
: 
: 
Fic. 13.—Diagram showing the nitrification of ammonium sulphate in samples of soil from different depths 
from plats 280 and 290, Truckee-Carson Experiment Farm. Original nitrate present in samples from 
plat 280: Depth, 0 to 6 inches, 12 parts per million; 6 to 12 inches, 10; 12 to 18 inches, 6; 18 to 24 inches, 
36 inches, 62.5. From plat 290: Depth, 0 to 6 inches, 60 parts per million; 6 to 12 inches, 60; 
15; 24 to 
DEPTH AT WHICH SAMPLES WEAE TAKEN. 
0706" 67012" 
127018” 
187024" 247036" 
12 to 18 inches, 55.4; 18 to 24 inches, 60; 24 to 36 inches, 60. 
TaBLE |I.— Nitrification in solution of samples of soil from plats 100, 110. 180, 190, 220, 
260, 270, and 280, Truckee-Carson Experiment Farm. Incubated at 28° C. 
| No. of 
| Ammonia to nitrite 
(parts per million).? | (parts per million) 3 
a | 
Nitrite to nitrate 
Depth | 
plat. ofsoil. | 
6 days. 
Inches. 
100 0-6 6. 50 
6-12 | 5. 00 
12-18 6. 50 
110 0-6 og 
6-12 Shes 
12-18 8. 00 
180 0-6 0. 00 
6-12 0. 00 
12-18 0. 00 
190 0-6 1. 00 
220 0-6 0. 00 
6-12 0. 00 
12-18 0. 00 
260 0-6 5. 00 
6-12 3. 00 
12-18 3. 00 
270 0-6 6. 50 
6-12 0. 00 
| 2801 0-6 SD 
6-12 1. 00 
12-18 1. 00 
12 days. | 10 days. | 20 days. 
| 
25 91. 60 96. 00 
25 64. 80 60. 00 
18 86.40 | 81.60 
15,4) ogee \eoweenes. 
20: abssc eee ee ee eee 
250 vil2Csr sce ee eee 
15 24. 00 86. 40 
15 3. 60 | 2. 40 
00 | 2.40 | 3. 00 
16 | 72.00 74. 00 
00 | 13.20 80. 00 
00 3. 60 5.32 
00 | 2. 40 5.60 | 
UZ | 765.80 74. 00 
10 57.60 | 54.40 | 
10 2. 88 17. 55 
20 9. 60 43.20 | 
00 8. 64 60. 00 
20 21. 60 81. 60 
20 40. 80 81. 60 
20 38.40 | 81.60 
1 Plat 280 is located in an old alfalfa field one-fourth mile north of Fallon. 
* Used medium for isolating nitrite bacteria. 
211 
3 Used medium for isolating nitrate bacteria. 
FARTS FER? MILLION OF SULPHATES. 
4) 
