Man 8,1924 
Effect of Nitrate on Prussic Acid in Sorghum 
721 
Table III .—Sorghum grown on Coloma sand, with and without nitrate application 
Lot. 
Jar number. 
Age of 
plants. 
Nitrate applied. 
j 
Average 
height. 
Average 
weight. 
Hydrocyanic acid 
(HCN). 
Per jar. 
Per acre. 
Per cent. 
Per plant. 
Days. 
i Gm. 
Lb. 
Cm. 
Gm. 
Mgm. 
J 
35 
69 
! None. 
None. 
36 
1. 0 
0. 0033 
O. 033 
J 
36 
69 j 
i- 25 
3i4 
56 
5- 5 
. 0627 
3-448 
K 
37 
89 1 
None. 
None. 
30 
1. 0 1 
None. 
None. 
K 
38 
89 
2. 00 
502 
51 
4. 0 
. 1360 
5. 240 
In the fourth column of Tables I, II, and III, is given the amount of 
nitrate added from the beginning of the experiment. As the nitrate 
was added in successive doses while the plants were growing, the amount 
present at any time was less than the total reported, since the plants had 
used some of it, and, further, there may have been some denitrification. 
The intention was to compare plants grown with scanty, moderate, and 
abundant supplies of nitrate, and the analyses reported indicate that the 
hydrocyanic acid increased with the amount of nitrate supplied, up to 
amounts beyond those usually considered advisable for field crops. 
A third planting was made in April, using fresh Thurston loam subsoil 
in wooden boxes, 1 foot square, and 8 inches deep. Muriate of potash, 
at the rate of 300 pounds per acre, and treble superphosphate, 600 pounds 
per acre, were stirred into the surface of the soil, the seed planted on 
April 2, and the sodium nitrate given in a single application five days 
after the planting, at which time the plants were about 1 inch high. 
Each treatment was in duplicate and in some cases in quadruplicate, and 
the growth and appearance of all the plants with each treatment were 
very uniform. This series gave the most concordant results of any, 
probably because of the more favorable time of the year for growth, 
April 2 to May 20. Both the size of the plants and the percentage of 
hydrocyanic acid increased throughout the series, but the plants in the 
boxes that were given 760 pounds of nitrate per acre showed a slightly 
less thrifty appearance than those with only 570 pounds (Table IV). 
Tabus IV .—Sorghum plants grown on Thurston loam subsoil with various amounts of 
nitrate, given in a single application 
Lot. 
Box 
number. 
Age of 
plants. 
Nitrate applied. 
Average 
height. 
1 
Average 
weight. 
Hydrocyanic acid 
(HCN). 
Per box. 
Per acre. 
Per cent. 
Per plant. 
L... 
39 
Days. 
33 
Gm. 
None. 
1 
Lb. 
None. 
Cm. 
28 
Gm. 
I. O 
None. 
Mgm. 
None. 
L... 
40 
33 
O. 5° 
47 - 5 
30 
I. 2 
’None. 
None. 
L ... 
41 
33 
1. 00 
95 -o 
35 
2. 6 
0. eft 60 
0. 42 
L... 
42 
33 
2. 00 
190. 0 
51 
4. O 
.0330 
1. 32 
L... 
43 
33 
4. 00 
380. 0 
48 
4. O 
. 0810 
3 - 24 
T.. . 
44 
33 
6. 00 
570.0 
53 
3 -o 
.0830 
2. 50 
L... 
45 
33 
8. 00 
760. 0 
46 
4.0 
. 1200 
4. 80 
M... 
46 
47 
None. 
None. 
28 
1. 0 
None. 
None. 
M...I 
47 
47 
• 50 
47 - 5 
41 
i- 5 
None. 
None. 
M ... 
48 
47 
1. 00 
95 - 0 
41 
3 -o 
• 0025 
•075 
M. . .1 
49 
47 
2. 00 
190. 0 
48 
4. 0 
.0037 
. 148 
M. .. 
50 
47 
4. 00 
380. 0 
58 
6. 0 
. 0140 
. 640 
M. .. 
5 i 
47 
6. 00 
570.0 
66 
8-5 
. 0290 
2. 460 
M...J 
52 
47 
8. 00 
760. 0 
69 
8-5 
. 0540 
4. 600 
