FIELD EXPERIMENTS WITH FERTILIZERS. 213 
both for feeding green and for mixing with corn for producing 
a mixed silage with a higher percentage of protein than would 
be obtained from corn silage alone. 
SOIL TEST EXPERIMENT BY THE STATION. 
This experiment is the seventh in a series planned as a rota- 
tion soil test experiment, the same kinds of fertilizers being 
used on the same plots year after year. Beginning with 1800, 
the crops grown on this field have been corn, potatoes, oats, 
cow peas, corn, potatoes, and oats. 
ARRANGEMENT OF PLOTS IN STATION EXPERIMENT. 
UNMANURED STRIPS SEPARATE THE PLOTS. 
t 



















EAST. 
PLOT o. | ELGiEY: 
PLOT: A: PLOTSx. 
ELOT*D. PLOT ooo. 
PnoreG. ELOU a, 
: PLOT 00. BLOT rs 
0 
; PLoT D. PLor E. 
0 PLOT’ E. Priore DD: ~ 
Z PLOTS E: Ete OC): . 
PLor G. PrOnaG: 
PLOT 000. PLoT B. 
Piot X. RLOTCA. 
Prot Y. PU 0; 
WEST. 
The field slopes gently to the south, but not enough to 
cause serious washing. ‘The soil is a heavy loam, and the 
subsoil is a yellow, clay loam. In 1889 it was noticed that the 
soil seemed to be poorer toward the west side of the field. 
For this reason the field was laid out into two half-acre expe- 
riments, the order of the plots on the two being reversed, as 
per diagram. 
The yields of the duplicate plots in each case are added in 
estimating the yield per acre. This helps to eliminate the 
errors due to irregularities of soil. Beside the regular soil 
test, two other plots were added—one (X) with a medium 
