EFFECT OF NITROGENOUS FERTILIZERS. EL3 
EFFECT OF NITROGENOUS FERTILIZERS UPON 
THE YIELD AND THE COMPOSITION OF CER- 
TAIN GRASSES, GRAINS, AND LEGUMES. 
Ey WoO] ATIWATER AND.C.S. PHELPS. 
Soon after its organization, in 1888, the Station took up 
the study of the effects of nitrogenous fertilizers upon the 
yields and composition of corn, oats, and mixed grasses. Field 
experiments on the different crops were undertaken, in continu- 
ation of a series which, for a number of years previous, had 
been conducted on farms in different places at the suggestion 
of one of us (W. O. A.). These experiments were carried on 
during a considerable period of years for the twofold purpose: 
first, of studying, by the effect upon the yields of different 
crops, the relative economy of different kinds and quantities 
of nitrogenous fertilizers when used with uniform quantities 
of mineral fertilizers (phosphoric acid and potash); and sec- 
ond, of studying the effect of the nitrogen of the fertilizer upon 
the percentage of nitrogen compounds (protein) in the plants. 
After a few years the Station began a series of experiments 
with several species of grasses. These were similar to the 
experiments with corn, oats, and mixed grasses, except that 
they were conducted upon very small plots. In these experi- 
ments, because the plots were so small, no attempt was made 
to study the effects of the fertilizers upon the yields. The 
crops were carefully sampled, however, and the effect of the 
nitrogen in the fertilizers upon the percentages of nitrogen 
compounds (protein) in the plants was determined. In some 
cases these experiments have been continued with the same 
species of grasses and the same fertilizers on the same plots 
for several years in succession. Within the past few years 
the Station has undertaken also a series of experiments upon a 
few of the legumes, for the purpose of comparing the effects~ 
of nitrogenous fertilizers upon the plants of this family with the 
effects of the same kinds and amounts of fertilizers upon plants 
ofthe grass family. 
Of all the constituents of fertilizers nitrogen is the most 
costly. In the standard commercial fertilizers at the present 
time (1899) nitrogen costs from 11 to 15 cents per pound, while . 
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