58 STORRS AGRICULTURAL EXPERIMENT STATION. 
acre higher than on the nitrate of soda plot (A)2. In the: €xe 
periment of 1900 phosphoric acid seems to have taken the lead 
in affecting the yields both of grain and of straw, while nitro- 
gen stood second in its effects. This was not the case in the 
oat experiments of this series in 1892 nor in 1896. Each of 
those years the best yield of grain on the plots with commercial 
fertilizers seemed to result from the use of nitrogen from nitrate 
of soda, although the plots supplied with phosphoric acid from 
dissolved bone-black gave the second best results. As in pre- 
vious years, the largest yields in the oat experiment for I900 
were obtained on the plots supplied with manure. This was 
probably due to the fact that in the soil of the manured plots 
there would be humus present, one advantage of which would 
be a tendency to check the evaporation of water, while the 
ptots supplied with commercial fertilizers would probably be 
deficient in humus, a condition that would favor evaporation. 
By continuing the experiments through a number of years, 
and thus repeating each crop several times, the inequalities 
and errors in results due to irregularities of the seasons are to 
some extent eliminated in the final averages. Corn, potatoes, 
and oats have each been grown three times thus far during the 
course of the experiment. The average of the yields for the 
three different years for each of these crops is given in the fol- 
lowing table summarizing the results of the past eleven years. 
The yields of oats in the experiment of 1900 are also given in 
the table in comparison with the average. From the results 
here summarized it will be observed that the yield of oats has 
been largest on the plot with stable manure. On the plots 
with the chemical fertilizer the average yield was largest on 
plot D, with nitrogen and phosphoric acid together, while that 
on plot C, with potash alone, was little larger than that on the 
plots without fertilizer. The indication is that on this par- 
ticular soil the oat crop needs to be liberally supplied with 
nitrogen and phosphoric acid. Considering the results of all 
the experiments with all the crops, there seems to be no 
striking deficiency of any one of the ingredients—nitrogen, 
phosphoric acid or potash—in this particular soil. The special 
requirements for fertilizers seem to be determined more largely 
by the needs of the particular crop than by peculiarities of the 
soil. 


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