June, 1911 
1 lb 
(•err**F* 
Bulletin 1 78 
The Agricultural Experiment Station 
OF THE 
Colorado Agricultural College 
THE FIXATION OF NITROGEN 
IN SOME COLORADO SOILS 
A Further Study 
BY 
WM. P. HEADDEN 
PUBLISHED BY THE EXPERIMENT STATION 
FORT COLLINS, COLORADO 
1910 
