May 24,1924 Significance of the Southwestern Desert Vegetation 765 
Table XIX.— Comparison of spring and fall soil conditions at the same stations 
in typical areas in the pickleweed association, Indio, Calif., 1915 a 
♦ 
Date of collection 
Date of collection 
Item 
Depth 
of 
soil 
Mar. 
sample 
No. 26 
Mar. 
5, 
sample 
No. 27 
Mar. 
sample 
No. 28 
Aver¬ 
age 
Sept. 
22, 
sample 
No. 26 
Sept. 
22, 
sample 
No. 27 
Sept. 
23 
sample 
No. 28 
Aver¬ 
age 
Moisture equivalent. 
Feet 
1 
21.1 
21.7 
26.4 
23.1 
21.5 
18.9 
21.5 
20.6 
2 
16.0 
24.1 
29.1 
23.1 
20.0 
19.9 
29.9 
23.2 
3 
21.2 
11.7 
21.6 
ia2 
23.2 
11.0 
20.1 
18.1 
4 
20.0 
13.1 
17.8 
17.0 
7.1 
9.1 
15.0 
10.4 
Wilting coefficient. 
1 
11.5 
11,8 
14.4 
12.6 
11.7 
10.3 
11.7 
11.2 
2 
8.7 
13.1 
15.8 
12.5 
10.9 
10.8 
16.3 
12.7 
3 
11.5 
6.4 
11.8 
9.9 
12.6 
6.0 
10.9 
9.8 
4 
10.9 
7.1 
9.7 
9.2 
3.9 
5.0 
8.1 
5.6 
Moisture content above or 
1 
+16.1 
+15.3 
+21.0 
+17.5 
+1.8 
+8.2 
+7.3 
+5.8 
below wilting coefficient. 
1 
+12.3 
+16.0 
+20.0 
+16.1 
+5.2 
+10.8 
+11.2 
+9; 1 
3 
+12.6 
+24.0 
+18.5 
+18.4 
+7.1 
+15.3 
+17.3 
+13.2 
4 
+15.7 
+21.7 
+25.1 
+20.8 
+6.2 
+12.5 
+16.7 
+ 12.0 
Salt content. 
1 
>2.50 
>2.50 
>2.50 
>2.50 
>2.50 
>2.50 
>2.50 
>2.50 
2 
>2.50 
2.50 
.59 
1.86 
2.20 
1.73 
.20 
1.38 
3 
>2.50 
.65 
.36 
1.17 
1. 45 
1.10 
.20 
.92 
4 
.68 
.36 
.40 
.48 
.24 
.91 
.18 
.44 
a All data in percentages of the dry weight of the soil. 
Table XX.— Soil conditions in September and October in typical areas of the 
pickleweed association, Indio, Calif., 1914 a 
Depth 
of 
soil 
Date of collection 
. 
Item 
Sept. 14, 
sample 
No. 9 
Sept. 22, 
sample 
No. 32 
Oct. 2, 
sample 
No. 58 
Oct. 14, 
sample 
No. 85 
Oct. 15, 
sample 
No. 89 
Oct. 15, 
sample 
No. 94 
Oct. 31, 
sample 
No. 103 
Average 
Salt content... 
Feet 
1 
1.90 
2.10 
>2.50 
.36 
>2.50 
2.10 
1.01 
1.78 
2 
.40 
1.52 
1.96 
1.73 
1.04 
>2.50 
1.10 
1.46 
3 
.21 
2.30 
.70 
1.50 
.76 
1.96 
1.01 
1.21 
4 
.18 
1.56 
.29 
.68 
. 16 
1.56 
1.04 
.78 
Water content..... 
1 
m 6 
d 
w 
w 
w 
d 
w 
2 
w 
m 
w 
w 
w 
sm 
w 
3 
w 
m 
w 
w 
w 
m 
w 
4 
w 
m 
w 
w 
w 
m 
w 
Soil type. 
1 
1« 
fsl 
fsl 
si 
si 
si 
c 
2 
1 
fsl 
fsl 
si 
si 
si 
c 
3 
si 
fsl 
fsl 
fsl 
fsl 
fsl 
c 
4 
1 
fsl 
fsl 
fsl 
fs 
fsl 
c 
a No soil moisture or moisture equivalent determinations were made on the soil samples of 1914. The 
data given are merely the field notes on the samples. Salt content data are stated in percentages of the dry 
weight of the soil. 
b m=moist soil; d=drysoil; sm=slightly moist soil; w=wet soil. 
«l=Joam; s=sand or sandy; f=fine; c=clay. 
Salinity 
Pickleweed indicates land that has an excessive amount of salt in the first 
and second feet, and often the third (Tables XIX and XX). The fourth foot 
is least saline, averaging approximately one-half of 1 per cent (Table XXXIV). 
The average salt content for the 4 feet of soil is about 13^ per cent. In places 
there is a uniform white layer of salt on the surface that resembles a covering 
of snow. 
