122 
Journal of Agricultural Research 
Vol. XXI, No. 3 
com, show a mean annual rootrot injury of 10.5 per cent, with a range 
from 1.1 to 31.9 per cent; those including sorghum, a mean of 6.5 per 
cent, with a range from 0.8 to 19.3 per cent; those including oats show 
a mean of 10.4 per cent with a range from 2.8 to 16.7 per cent. It is 
clear from these figures that these different crops do not effect differently 
the rootrot injury on succeeding crops of cotton. 
Table III .—Percentage of plants killed by rootrot in the various two-year rotations at 
the San Antonio Experiment Farm, IQ12 to 191Q 
tation and plot No. 
1912 
1913 
1914 
1915 
1916 
1917 
1918 
1919 
Rota¬ 
tion 
mean. 
JA4-I. 
0. 1 
i -3 
4-7 
48.6 
1 
Aa-2. 
0 
0 
7 . 2 
26. 5 
f IO - s 
[Aa -7 . 
i -5 
14. 0 
o' 
29. I 
2 7 - S 
J 
) 
' A4-8... 
0 
0 
12-5 
13.0 
19-3 
9.8 
f ! 3 -o 
M5-7. 
A5-8.. 
0-3 
. 2 
J 
1 
2.1 
11. 6 
17-3 
39 -0 
\ II -7 
/A 5-9. 
0 
. 1 
l8. O 
30. 0 
J 
A5-10... 
. 7 
4 * 3 
14-3 
5-6 
I S- 0 
24. 8 
S 9 -o 
t 10.4 
/A5-11.. 
\A5-12. 
. 2 
I. I 
. 2 
22. 6 
21. 2 
J 
} 16.7 
, A 5-13. 
. 2 
0 
43*2 
46.9 
J 
1 
15-14. 
1. 2 
6.7 
20. 8 
35-4 
\ 19-3 
/A5-15. 
, 7 
1.4 
14. 8 
4. O 
} 2.8 
\A5-16. 
. 1 
0 
. 2 
i -5 
/A 5 -I 7 . 
\A5-18. 
0 
0 
7. 7 
■3 A 
0 
. 2 
o' 1 
1. 6 
0 
O' T 
•9 
. 3-3 
J 1,2 
fa . 
0 
0 
} - 8 
\io. 
0 
. 1 
2. 2 
. A 
0 
. 2 
0 
8.6 
{12. 
0 
, 1 
5-6 
II. O 
f 3 ‘ 2 
/17. 
2. 2 
i -3 
4.1 
j 
\i8. 
.6 
. 7 
•3 O 
8. I 
4 . 9 
} 4-3 
fi. 
. 7 
0 
2. 0 
\ 
{2. 
0 
0 
.8 
2 
J 1,1 
0 
0 
1-3 
8. 0 
{4. 
. 1 
0 
.8 
6.8 
J 2,1 
/5 . 
0 
. A 
•3 
i -7 
) 
\6. 
.6 
0 
1.9 
I I - 1 
f 7. 
0 
O 
. 0 
8-3 
3 * 9 
\8. 
0 
. 2 
1. 0 
5-4 
} i -9 
0 
. tr 
4-5 
13-8 
J 
. 2 
0 
2. 7 
3-9 
12. 6 
[4-7 
In.. 
1. 1 
3. 5 
51-8 
6- 5 
) 
1 
{12. 
. 7 
7 n 
l 12.4 
/13. 
2. 5 
12. 8 
o' y 
98. 2 
»• S 
21. 3 
J 
) 
\i 4 . 
13. 2 
45-7 
23. 2 
51-3 
r 31-9 
/15. 
2. 0 
4.8 
8l. 7 
5-5 
J 
\ 
\i6. 
1. 6 
14. 2 
36.6 
63. 6 
7 26.3 
/17. 
. 7 
.6 
15-5 
3 i -4 
J 
\ 
\i8. 
.6- 
. A 
> II. 2 
. 
•••'1 
• 5 
40. 7 
J 
A-4a 
A-4d 
A-5C1 
A-5C2 
B-sa 
B- 5 b 
B-se 
B—6a 
B-6b 
B-6c 
B-6d 
B-6e 
B-6f 
B-6g 
B-6h 
B-6i 
3. Effect of subsoiung. —Among the 20 two-jear rotations there 
are five pairs of which the members of each pair differ from each other 
only in that in one case the land is plowed to the ordinary depth of 
about 8 inches, while in the other case the plow is followed once during 
the rotation with a subsoil plow which breaks the ground in the furrow 
