TILLAGE AND ROTATION EXPERIMENTS AT NEPHI, UTAH. 39 
the previous year. In 1911, however, under favorable conditions, 
the yields w r ere consistent with the soil moisture. In 1912 there 
was little difference either in moisture or yield. 
These results indicate that where a good stand is obtained in the fall 
and little winterkilling follows, the crops following fallow will yield 
more than those grown on continuously cropped land. To determine 
the relative value of the two systems of cropping, the cost of growing 
a crop and of maintaining a fallow must also be taken into consid- 
eration. In the vicinity of Nephi, the cost of growing and harvest- 
ing wheat is about $3 per acre more than the cost of maintaining a 
fallow r throughout the year. This extra cost must be charged 
against the crop which is obtained in alternate years on the con- 
tinuously cropped land. On this basis, the 14 bushels greater yield 
per acre in 10 years from the land continuously cropped have been 
obtained at a cost of $15, for the $3 extra cost has been incurred 
five times in the 10 years. This extra cost is greater than the value 
of the increased yield, which is further evidence that alternate crop- 
ping and fallowing is preferable to continuous cropping to wheat. 
INTERTILLED CROPS COMPARED WITH FALLOW IN 
WHEAT. 
ALTERNATION WITH WINTER 
The most direct attempt made at the Nephi substation to find a 
successful substitute for the alternation of a cereal crop and summer 
fallow has been in a simple rotation in which winter wheat was 
grown after fallow and after corn, peas, and potatoes in rotation. 
As this test has been in progress since 1908 sufficient data have been 
accumulated to justify consideration at this time. An outline of 
the rotation is given in Table XVII. 
Table XVII. — Rotation of intertilled crops and fallow alternating with wheat. 
Plat. 
1908 
1909 
1910 
1911 
1912 
1913 
12B 
Wheat.... 
...do 
Fallow. . . . 
Corn 
Wheat 
...do 
Fallow 
Wheat.... 
...do 
Fallow. 
13B 
14B 
...do 
...do 
Fallow 
Potatoes . . 
Potatoes . . 
Peas 
Wheat.... 
...do 
...do 
...do...:.. 
...do 
Fallow 
Corn 
...do 
Peas. 
15B 
12C 
Potatoes . . 
Wheat.... 
...do.. 
...do 
Fallow.... 
Peas 
Corn 
Potatoes . . 
Corn. 
Wheat. 
13C . . . 
Do. 
14C 
Potatoes . . 
Peas 
...do 
...do 
Do. 
15C 
Corn 
...do 
Do. 
TREATMENT OF PLATS. 
The four plats which had grown wheat were plowed in the fall of 
each year to a uniform depth of about 8 inches. The land then 
received no cultivation until the next spring, when it was double 
disked or harrowed sufficiently to destroy all weeds and make a good 
fallow or a good seed bed. The plat to be summer-fallowed was 
treated normally in the spring and throughout the summer. The 
