42 The Colorado Experiment Station. 
this far apart, were chosen was because we could not get a good 
view of an unaffected tree standing in the next row and contiguous 
to the dead tree represented by the lower photograph. 
In a preceding paragraph I stated that on May 30, 1911 the 
trees were burning badly in the southwestern portion of the orchard, 
as many as six or eight consecutive trees in a row being attacked 
and dying in the same manner. On June 23 I counted thirty-five 
consecutive trees in one row which were all attacked to a greater or 
less extent. Of these thirty-five trees not less than twenty-five 
were already dead and of the remaining ten five were already so 
badly injured that there was no hope of their recovery. 
Case No. 15 — Under this number I shall present two adjacent 
orchards, without going into any details. I first noticed one of 
these orchards about four years ago. At that time about one and 
a half acres of the land was bare; the few trees that were still 
standing were dead. The surface of the soil was brown. I visited 
this orchard in 1909 and-took a sample of the soil to a depth of 
one foot. The condition of the land did not appear to be very 
bad but it had been recently cultivated which operation effectually 
conceals this condition if carefully done. This sample yielded 
3.580 percent of water-soluble which afforded the following results: 
ANALYSIS LIII 
Water- 
Soluble 
Laboratory- 
No. 779 
Percent 
Calcic sulfate . 30.528 
Magnetic sulfate . 19.901 
Potassic sulfate .. ... 1.878 
Sodic sulfate . 23.006 
Sodic chlorid . 12.951 
Sodic nitrate . 18.307 
Manganic oxid . 0.267 
Silicic acid . 0.162 
100.000 
This analysis indicates the presence of a little more than 13 
tons of sodic nitrate to the acre-foot. 
There is another orchard immediately to the north and east 
of this to which my attention was directed in the spring of 1911. 
Drains were laid in this land in the autumn of 1910 with the idea 
of washing the soil by heavy irrigation and depending upon the 
drains to carry off the leachings of the soil with the excessive 
water which might be added or which might possibly accumulate 
from other sources. The soil is a sandy loam passing into a clayey 
loam in places. The water plane, determined by means of a series 
of wells, was four and a half feet below the surface. Some of the 
