34 The Colorado Experiment Station. 
them one and a half inches deep; this gave 1.45 percent soluble in 
water and showed very little nitric acid. The other sample was 
taken to a greater depth, eight inches, and showed the presence of 
1.762 percent water-soluble and a very decided quantity of nitric 
acid. 
ANALYSES 
XLI 
XLII 
Water-Soluble 
Water-Soluble 
Laboratory 
Laboratory 
No. 876 
No. 877a 
Percent 
Percent 
Calcic sulfate . 
43.457 
Magnesic sulfate . 
19.658 
Potassic sulfate. 
10.206 
Potassic chloric! . 
4 458 
Sodic sulfate . 
1.030 
Sodic chlorid . 
13.494 
Sodic nitrate . 
11.373 
Iron and Aluminic oxid . 
. 0.193 
0.147 
Silicic acid . 
0.635 
100.000 
100.000 
It is seldom that we have so great a difference in the character 
of the soluble salts in samples of soil from the same place. This 
is probably due to the heavy irrigation that this land had just 
received. It had apparently moved the whole of the nitric acid 
down into the soil to a greater depth than one and a half inches 
and most of the sodic and potassic salts with it. In this respect 
these two analyses are quite interesting. The eight-inch sample 
.shows the presence of 5^344 pounds per acre in this section of 
soil, or a little over four tons to the acre-foot. 
Case No. 12— This is one of the worst cases that I have 
observed. The soil is sandy and the orchard is contiguous to 
Orchard No. 11 and west of it. In June, 1910, I observed the 
beginning of a very general burning in the orchard and a few 
trees, perhaps twelve to twenty, were already dead or in a bad 
condition. I spoke to the owner in regard to the matter but he 
thought that it was a case of spray burning and attributed the 
trouble to a faultily prepared lead arsenate. He was very positive 
in regard to the matter. I saw this orchard in September when it 
was in a very bad condition, probably upwards of six acres being 
involved and very many of the trees will not survive the season. 
The conditions of this orchard are the same as in Orchard No. 11, 
and there is no question of drainage or alkali. Both orchards are 
fairly old ones, the oldest trees being probably not less than sixteen 
years and the youngest twelve to fourteen years old. When the 
owner of Orchard No. 12 became convinced that something more 
serious than spray burning had happened to his trees he manured 
the land and irrigated heavily. The development of this orchard 
