8 Tiie Colorado Experiment Station. 
half feet deep at the same place, where we dug to the depth of five 
and a half feet on November 3. At this depth the ground was 
very wet, even muddy. We waited a short time to see whether 
any free water would flow in but it did not. On May 14 1010 
I again visited this orchard. The condition of the orchard was 
vci> bad many trees had been removed and many more were 
,, yln |- , J une lr > I 9 IO » almost exactly a year subsequent to 
the first observations made on these dying trees, I visited it again. 
- 7 r h , aU Was , rumed; most of the trees were dead; and worse 
yet, the land, so lar as we can now see, is as thoroughly ruined 
as the orchard. A large portion of this orchard—six to eight 
acres—has been dug up. S 
The orchard immediately south of this one is in a very bad 
condition; it is, for the most part, dead. No samples of either the 
soil or the ground water were taken at this place. The owner a 
man of considerable education, is fully convinced that the trouble 
is not due to excessive water in the soil. 
1 he following samples of surface soil from Orchard No. ; 
W1 conve y a better idea of the conditions existing in this soil than 
any words describing them. In No. 947-a the water-soluble equalled 
Ilf’ \ n 959 , 34; m No. 995, 12.79, and in No. 1013, 7.20 
percent of the air-dried soil. ^ 
ANALYSES H 
Water-Soluble 
laboratory 
No. 947a 
May 14, 1910 
Percent 
Calcic sulfate. 18.437 
Calcic chlorid. 14 773 
Magnesic sulfate ...... _ 4 
Magnesic chlorid. 10.474 
Potassic sulfate. . _L_ 
Potassic chlorid. 2.273 
Sodic sulfate .’_1_ 
Sodic chlorid . 13 726 
Sodic nitrate . 39.79 0 
Iron and Aluminic oxids. 0.132 
Silicic acid . 0.210 
100.000 
III 
Water-Soluble 
laboratory 
No. 159 
June 11, 1910 
Percent 
20.437 
5.999 
1.447 
15.104 
35.416 
21.303 
0.149 
0.235 
100.000 
IV 
Water-Soluble 
laboratory 
No. 995 
Aug. 25, 1910 
Percent 
8.219 
17.005 
12.295 
1.434 
8.747 
52.071 
0.090 
0.139 
100.000 
V 
Water-Soluble 
laboratory 
No. 1013 
Sept. 13, 1910 
Percent 
9.123 
20.415 
10.65S 
1.575 
27.708 
30.350 
0.051 
0.111 
100.000 
1 he dates on which the various samples were taken, extending 
over two years and representing the months of May, June, August 
September and November, show that the condition is a persistent 
one, and while it may vary from month to month there was a very 
dangerous quantity of nitrates in this soil throughout the whole 
M vi 1 w ti • 
., b, • J P °9 I produced decided injury to four-year-old trees by 
the addition of five pounds of nitre to the soil, within a radius of 
