AGDELL FIELD EXPERIMENTAL ROTATION SOILS. 
17a 
Table 90.— Agdell field experimental rotation land, etc— Continued. 
MIXED MANURE. 
Samples collected in 
Fallow : 
Roots carted . 
Roots fed .... 
M.-Jin 
Beans or clover: 
Roots carted 
H< i',t> fed 
Maaa 
Mean <<f nil 
Carted: 
Fallow 
Beans or clover . 
Mean 
Fed: 
Fallow 
Beans or clover. 
Mean 
HMO of all 
Plats. 
") and 8 
1 and 2 
7 and* 
3and 4 
5 and 8 
7 and 8 
1 and 2 
3und t 
Novem- 
alter 
Octol>er. 
1-71 after 
clover). 
Novem- 
ber. 1888, to 
January. 
ism (after 
wheat i. 
Mean. 
Pounds per 
acre. 
8,010 
1, 197 
I'on mis per 
acre. 
t, 9&1 
2.940 
Pounds jier 
tieri . 
2,918 
2. 888 
Pounds pi r 
acre. 
2. scis 
3. H41 
3. lt>4 
2.914 
!•.->_' 
8,880 
8,088 
3. |M 
3.09i; 
3, 293 
3,012 
:;. MK 
8,048 
3. 888 
3,116 
3.195 
3. 210 
3.174 
3.11(1 
3.(154 
3.081 
3.082 
3.010 
8, MB 
•.' B81 
3. 09(1 
8,818 
3.(112 
2. 888 
3,(449 
3.021 
2.992 
2.965 
2.994 
s, m 
8, r.»i 
2.940 
8, M 
2. 98.; 
3. 408 
3JU1 
3, 298 
::. 1!h; 
3,117 
3. 197 
3. 170 
3.110 
3,054 
3.osl 3,062 
SUMMAB1 
Unmannred 
3.082 1 
8,108 
Sui>erphosphate 

Mixed manure 
3.110 
8,018 
8,801 
3.054 
2. 927 
8,886 
3.081 
3.008 
2.980 
3.082 
As far as the unmannred plats arc concerned, the growth of roots 
was for the greater pari of the time so small that it may be said that, 
practically speaking, there was no crop of roots cither to cart or to 
feed. 
When we come to the superphosphate plats, however, the consump- 
tion of the roots on the land has greatly affected tic fertility of ihe 
soil. There being no supply of manurial nitrogen, the strain on the 
nitrogen contents of the soil in this rotation has been great, and 
the exhaustion of the soil nitrogen has necessarily been much greater 
on the "carted" portions of the plats than on those on which the roots 
have been consumed. On the whole, it will be seen that in the fallow- 
rotation plats of the superphosphate series analysis indicates a larger 
proportion of nitrogen in the "fed" plats than in the "carted" plats, 
this being especially marked in the samples taken in 1883-84, at the 
end of thirty-six years, or nine rotations. This superiority in nitro- 
gen contents accords with the greater fertility of the soil, as evidenced 
in its crops. 
On the leguminous portions of the plats (beans or clover instead 
of fallow), where, as we shall see presently, there is more nitrogen to 
