30 
CoivORADO Experiment Station 
creases showed an abundance of these salts. The corn was good. I 
wondered why the corn was alive. I took a sample of the surface soil 
at a spot where the corn was not as thrifty as most of it was. This 
sample of soil carried more than 4.5 percent of salts which were soluble 
in water. These salts consisted, for the most part, of calcic, magnetic 
and sodic sulfates with more sodic chlorid than usual, but no carbonates. 
Practically 70.0 percent of this soluble portion was made up of these 
sulfates, with only a moedrate amount of calcic sulfate, 16.6 percent 
of the total soluble matter. I mention this in particular because this 
calcic sulfate is very common in our soils and alkalis, often making up 
a big part of the white coating on the ground, further, because it is 
not very poisonous, but the lime salts do seem to be poisonous under 
some conditions. This case was even more interesting than the state¬ 
ments so far made suggest. The land was not only at that time full of 
alkali, a little more than 4.5 percent of the soil being soluble in water, 
but the owner was irrigating it freeley with seepage water, that car¬ 
ried 16,414 pounds of salts in each acre-foot of water. A good, open,, 
loamy soil will take an acre-foot if it is dry enough to really need irri¬ 
gation, and the soil is able to hold back a great many salts when such 
water sinks through it; besides, from 20 to 30 inches of water will evap¬ 
orate from the surface of the soil and leave the salts that it held in 
solution. I do not know how much corn the man got to the acre, but 
it promised to give a fair crop. This land was planted to wheat the 
next season and again irrigated with this seepage water. I saw it just 
before harvest and it was far above the average. I subsequently learned 
that the yield was about 60 bushels to the acre. 
In another instance, a beet field, I measured the incrustation be¬ 
tween the rows, practically beneath the leaves, for they almost covered 
the ground. This incrustation was three-sixteenths of an inch thick. 
This case was much worse than the preceding for the land had been 
irrigated with seepage water and the ground-water was within 18 
inches of the surface. The incrustation as gathered contained 51 per¬ 
cent, of water-soluble material which was made up of magnesic and 
sodic sulfates, together 80.0 percent with lo.o percent of sodic chlorid. 
There was very little calcic sulfate in this incrustation. The water- 
soluble in the upper portion of the soil, but not including the incrus¬ 
tation, was 3.6 percent; 44 percent of which was calcic sulfate, 21 per¬ 
cent magnesic sulfate and 20.5 percent sodic sulfate. There were less 
than i.o percent of carbonates and 4.2 percent of sodic chlorid. There 
was, in the top 6 inches of this soil, after scraping off the incrustation, 
70,000 pounds of soluble salts to the acre. This land was in a river 
bottom and parts of it are sometimes flooded to such an extent as to 
drown out the crops. This land was planted to beets three years in 
succession. I got the record of the production for the second and third 
years. It was 9 and 10 tons respectively with a sugar content of 16.0 
