42 
BULLETIN 157, U. S. DEPARTMENT OF AGRICULTURE. 
Wheat after corn gave the highest yield obtained in 1909, while 
wheat after fallow yielded better than wheat after either potatoes or 
peas. The yields of 1909, however, were extremely low because of 
excessive winterkilling. Consequently they would be practically 
worthless if they were not relatively the same as those obtained in 
later years. In 1910 wheat after fallow yielded much less than wheat 
after any intertilled crop. In 1911 wheat after potatoes gave the 
highest yield, while there was little difference in the yields of the other 
plats. Wheat after fallow again gave the lowest yield in 1912 and 
1913. A summary of the wheat yields obtained in this test for the 
five years from 1909 to 1913, inclusive, is given in Table XIX. 
Table XIX. — Annual and average yields of winter wheat obtained after corn, potatoes, 
and fallow, at the Nephi substation , for the years 1909 to 1913, inclusive. 
Rotation. 
Yield per acre of grain (bushels). 
1909 
1913 
Average. 
Wheat after corn 
Wheat after potatoes 
Wheat after peas 
Wheat after fallow. . 
6.50 
2.50 
2.16 
4.66 
19.30 
17.20 
18.30 
13.10 
28.50 
32.10 
29. 50 
30.00 
18.80 
18.70 
17.80 
14.70 
4.40 
4.20 
4.20 
2.00 
15.50 
14.94 
14.39 
12.89 
Table XIX shows that the average yield of wheat for five years 
was less after fallow than after corn, potatoes, or peas. 
A summary of the total crop yields of all plats since the test began 
is given in Table XX, where it will be noticed that plats 12B and 
12C, wheat after fallow, have given the lowest total returns per acre. 
Table XX. — Summary of total crop yields from the intertillage and fallow rotation plats 
at the Nephi substation, 1908 to 1913, inclusive. 
Total yields per acre. 
Years and plats. 
Wheat. 
Corn. 
Peas. 
Potatoes. 
Grain. 
Fodder. 
Seed. 
Hay. 
1909 to 1913: 
12B 
Bus. 
28.40 
37.10 
36.00 
37.00 
36.66 
35. 20 
38.66 
40.20 
Bus. 
Lbs. 
Lbs. 
Lbs. 
Bus. 
13B 
None. 
None. 
2.9 
1,240 
40 
550 
Failure. 
20 
None. 
Failure. 
95 
1,050 
34.50 
14B 
84.70 
15B 
4.00 
1908 to 1913: 
12C 
13C 
None. 
None. 
17.5 
40 
1,420 
630 
90 
220 
None. 
225 
1,080 
35 
42.50 
14C 
7.35 
15C... 
32.40 
Table XX shows that the wheat yields on the a B" series are 
greatly in favor of the plats which produced an intertilled crop in 
alternate years, the differences in acre yields varying from 8 to 9 
bushels. In addition to yielding as much wheat as plat 12C, the 
