506 
Journal of Agricultural Research 
Vol. XIV, No. n 
It appears from these results that no significant differences in the 
yields have resulted from the differences in preparation. There are no 
greater differences exhibited between the deep-tilled or dynamited plots 
and those not so treated than are shown between the same plots when 
the preparation of the land was uniform, or are shown between rotations 
503 and 504, which are practically the same in their treatment. 
Table XIV.— Yields at the Hays ( Kans .) Field Station for the years IQ14 to igi6 , 
inclusive , from four 3-year rotations of fallow , winter wheat , and kafir , showing the 
results of dynamiting and deep tillage of fallow 
Rotation and crop. 
Yield in busbels. 
Ratio of yield to mean. 
1914 
1915 
1916 
1914 
19x5 
1916 
Rotation 501: 
Fallow, deep-tilled... 
Winter wheat.. 
24. 8 
14.9 
38.8 
98 
108 
107 
Kafir.. 
2. 6 
5 i- 2 
12.7 
52 
104 
105 
Rotation 502: 
Fallow, dynamited. 
Winter wheat.. 
24. 2 
13.5 
32.9 
06 
98 
91 
Kafir... 
5 -° 
46.4 
9.5 
100 
94 
79 
Rotation 503: 
Fallow, listed. 
Winter wheat. 
25- 5 
14 4 
35.5 
100 
104 
98 
Kafir. 
6. 4 
46.8 
11.4 
128 
93 
94 
Rotation 504: 
Fallow, listed. 
Winter wheat. 
26. Q 
12. 5 
37.8 
106 1 
91 
104 
Kafir. 
5-9 
52. 2 
14 7 j 
118 
106 
121 
AKRON FIELD STATION 
deep tillage by the use op dynamite 
At the field station at Akron, Colo., a square of prairie sod was divided 
checkerboard fashion into 16 plots each 4 rods square, separated by the 
necessary alleys, making 0.1 acre in each plot. The designation of the 
plots by letters is similar to that at Ardmore (fig. 4). On August 26 and 
27, 1912, the two center tiers of plots running north and south were 
dynamited. The soil was quite dry at this time. Twenty per cent 
dynamite was used, the shots being placed 15 feet apart, 16 holes to the 
plot. The shots were fired at a depth of 30 inches, % pound of dynamite 
being used for each charge. After a rain which put the soil in good con¬ 
dition the entire block of plots was broken, September 16 to 18, and the 
sod rolled flat with a roller. 
In the spring of 1913 the eight plots on the north, four of which had 
been dynamited and four of which had not, were given the necessary 
disking and harrowing to make as good a seed bed as possible, and were 
