58 BULLETIN 1377, U. S. DEPARTMENT OF AGRICULTURE 
Table 52. — Relative value of crop rotation in maintaining soil productivity 
Crop 
Station 
Kind of fertilizer 
used 
Wheat... Rothamsted. 
Columbia, Mo. 
Wooster, Ohio 
Corn j Columbia, Mo. 
Wooster, Ohio 
Urbana, 111.... 
Columbia, Mo. 
Wooster, Ohio 
Rothamsted.. 
Oats. 
Barley. 
Chemical fertilizer.. 
I do 
\Manure. 
I Chemical fertilizer.. 
,\Manure 
1 do... 
(Chemical fertilizer. . 
\Manure 
Phosphates and ma- 
nure. 
Manure 
/Chemical fertilizer.. 
(Manure 
Chemical fertilizer.. 
Average yield at 
Rela- 
beginning of test- 
tive 
maintenance yield 
value 
for crop- 
rota- 
Period of 
experi- 
Aver- 
age 
yield 
for ro- 
tation 
alone 
Aver- 
age 
tion, as 
com- 
ment 
yield 
pared 
covered 
Five- 
for use 
with 
by study 
Years 
year 
of fer- 
ferti- 
(years 
selected 
average 
tilizer 
lizers, 
inclusive) 
for 5-year 
mainte- 
alone 
in 
average 
nance 
yield 
main- 
taining 
soil 
produc- 
tivity 
Bushels Bushels 
Bushels 
Percent 
1851-1921 
1846-1850 
17.5 
24.1 
23.6 
102.2 
1695-1918 
» 1889-1894 
14.2 
22.8 
27.6 
82.6 
1895-1918 
1889-1894 
14.2 
20.1 
20.1 
100.0 
1899-1918 
1894-1898 
10.5 
12.0 
19.7 
60.9 
1899-1918 
1894-1898 
10.1 
12.1 
17.1 
70.8 
1894-1918 
1889-1893 
33.5 
39.3 
33.8 
116.2 
1899-1918 
1894-1898 
29.0 
26.4 
34.4 
*76.7 
1899-1918 
1894-1898 
27.2 
26.6 
28.2 
94.3 
1904-1916 
1899-1903 
41.6 
51.2 
32.6 
" 157. 1 
1895-1918 
i 1889-1894 
23.6 
28.9 
34.2 
84.6 
1899-1918 
1894-1898 
27.8 
32.2 
38.8 
83.0 
1899-1918 
1894-1898 
26.4 
32.3 
29.6 
109.1 
1857-1921 
1852-1856 
27.4 
21.0 
42.0 
* 50. 
• Yield for 1 year is omitted, and 1 year the crop failed. 
1 Average yield on check plot in continuous culture is 13.3 bushels. 
* Average yield on check plot in continuous culture is 23.4 bushels. 
'Average yield on check plot in continuous culture is 14.1 bushels. 
In the table it is to be noted that, under the conditions of the 
experiments considered, crop rotation without the use of fertilizer 
maintained the producing power of the soil, except in the case of corn 
at Wooster and of barley at Rothamsted, and the use of fertilizer 
without rotation maintained the producing power of the soil, except 
in the case of corn at Urbana. 
