The Ammonifying Efficiency of Certain Colorado Soils. 9 
for ammonification, I was overwhelmed with astonishment, to put 
it mildly, to see the whole barren portion almost entirely covers 1 
with saltbush (Atriplex) w.aist high. Unfortunately, before I was 
able to obtain a photograph of this, the owner had burned over the 
area to destroy the weeds. However, I did get a picture later, after 
the fire had swept across, which will convey to the reader some 
idea of the luxuriance of the vegetation, although it gives no ade¬ 
quate conception of the height of the growth. (Eig. 3.) Durinlg 
the winter and spring of 1910 and 1911, the precipitation was un¬ 
usually heavy in this region. The accumulation of nitrates in the 
surface layers had evidently been carried down by leaching until 
the concentration of the salts had been reduced to a point wher*e 
the weeds could grow, and when once established, they had utilized 
the. nitrates to the best of their ability in making a rank growth. 
This was the firs't instance in which we had ever observed anything 
that even suggested self reclamation of a niter area. Since then, 
one other locality has come to our notice. 
The soil is a clay loam, and the sample for the ammonification 
experiment was taken between two burning trees in the last surviv¬ 
ing row. The results of the examination give the following per- 
Figure 3. 
