106 BULLETIN 699, U. S. DEPARTMENT OF AGRICULTURE. 
Considering the results obtained during the third period of the 
experiment the yields of miscellaneous crops in 1903 were on the 
whole considerably greater on the soluble-phosphate plots and those 
treated with basic slag and ground bone than on the raw rock phos- 
phate plots. 
In 1904 the raw-rock plots (limed and unlimed) gave smaller?! 
yields of oat hay than any of the soluble-phosphate plots, with the 
exception of double acid phosphate (unliimed.) The yields of hay 
from the raw-rock plots, however, in 1905 and 1906 compan quite 
favorably with those of the other phosphate plots. 
The yields of most of the miscellaneous crops grown in 1907 were 
greater on the soluble phosphate, bone, and basic-slag plots than on 
those treated with raw rock phosphate, but the average yield ob- 
tained on plots treated with the latter material were very much 
greater than those of the check plots. 
In 1908 the yield of whitecap corn from the raw-rock plot 
(unlimed) was greater than that from any of the soluble-phosphate - 
plots, but did not equal the yields of the ground-bone and basic-slag 
plots. On the limed series, however, the yields of corn were greater 
on the basic-slag, bone, and soluble-phosphate plots. The results with 
the few rows of turnips grown this same year on the limed series 
were more favorable to raw rock phosphate than to any other phos- 
phate application, but on the unlimed series basic-slag treatment 
showed to much greater advantage. 
In 1909 the yield of potatoes from the raw-rock plot (limed 
and unlimed) was exceeded by all the other phosphate plots except 
raw Redonda, dissolved bone black (unlimed) and double super- 
phosphate (unlimed). The rye which was planted in 1909 and 
harvested in 1910 gave considerably better yields on the plots (limed 
and unlimed) treated with slag, bone, and the soluble phosphates 
than on the raw-phosphate plots. The same was true of Hungarian 
hay which followed rye. In 1911, however, the yields of oats on 
the raw-rock plots compared very favorably with the yields from — 
the plots which had received equal amounts of phosphoric acid in 
other forms. The hay crops in 1912 and 1913 were somewhat better 
on the slag, bone, and soluble-phosphate plots than on those treated 
with raw rock, but the yields of turnips this same year from the 
raw-rock plots compared favorably with those from the plots receiv- 
ing other phosphates, except dissolved bone black and basic slag 
(unlimed). 
In summing up the results of this long-time experiment it can be 
said that distinct increases in yields were obtained from the use of 
raw rock phosphate. In nearly every case where this material was 
applied in quantities supplying from two to three times as much 
phosphoric acid as acid phosphate it compared favorably with the 
‘ wane 4 —— 
BEM per ing 
