48 
BULLETIN 1377, U. S. DEPARTMENT OF AGRICULTURE 
four crops mentioned in Table 47, which are described in the fore- 
going paragraphs. 
In Table 49 are given the analyses of the average yields of these 
four crops for the periods indicated in Table 47, when rotation and 
the use of fertilizers are practiced independently of each other. 
Table 49. — The comparative effects of crop rotation and of the use of fertilizers on 
the yields of crops on limed and unlimed soils 
(Rotation and the use of fertilizers practiced separately] 
Crop 
Cultural conditions 
Average 
yield per 
acre 
Increase 
over check 
plot in 
continuous 
culture 
Relative 
value of 
rotation, 
as com- 
pared with 
fertilizers, 
in effect- 
ing larger 
yields 
Wheat (Wooster) 
Limed: ' 
Rotation without use of chemical fertilizer .. 
Rotation without use of manure 
Unlimed: 
Rotation without use of chemical fertilizer. . 
Use of chemical fertilizer without rotation... 
Bushels 
16.0 
16.2 
14.1 
20.5 
7.2 
14.2 
18.9 
7.9 
31.1 
31.2 
26.9 
34.1 
13.5 
27.0 
28.0 
9.4 
35.1 
35.6 
32.3 
37.9 
18.7 
32.9 
28.4 
19.3 
Pounds 
1,584 
1,860 
1,215 
1,648 
1,877 
1,289 
Bushels 
Per cent 
6.9 
13.3 
51.9 
6.3 
11.0 
57.3 
No rotation and no manure 
Corn (Wooster).. 
Limed: 
Rotation without use of chemical fertilizer.. 
Rotation without use of manure 
Unlimed: 
Rotation without use of chemical fertilizer.. 
Use of chemical fertilizer without manure. . . 
13.4 
20.6 
65.0 
Rotation without use of manure 
17.6 
18.6 
94.6- 
Use of manure without rotation 
Oats (Wooster). .. 
Limed: 
Rotation without use of chemical fertilizer.. 
Unlimed: 
Rotation without use of chemical fertilizer.;. 
Use of chemical fertilizer without rotation... 
13.6 
19.2 
70. & 
13.6 
9.1 
149.5 
Cotton (South 
Carolina.) 
Limed: 
Rotation without use of chemical fertilizer.. 
Use of chemical fertilizer without rotation... 
Pounds 
369 
645 
57.2 
Unlimed: 
Rotation 
359 
588 
61.1 
Use of chemical fertilizer without rotation... 
» No lime is applied to the plots in continuous culture at Wooster. 
The data in Table 50 show that the yields of wheat, corn, and oats 
are higher on the limed than on the unlimed soils. Cotton has not 
responded to liming. Altering the soil reaction has caused a decline 
in the relative value of rotation in the case of cotton. The absence 
of liming tests in continuous culture makes it impossible to deter- 
mine the relative values of rotation in case of wheat, corn, and oats, 
under conditions when rotation and the use of fertilizers are prac- 
ticed apart from each other. 
In Table 50 are summarized the data on the yields when rotation 
and the use of fertilizers are conjoined. 
