May 24,1924 Significance of the Southwestern Desert Vegetation 
775 
Table XXVI. — Comparison of spring and fall soil conditions at the same stations 
in typical areas of seepweed , Indio, Calif., 1915 a 
Date of collection 
Date of collection 
Item 
Depth 
of soil 
1 
Mar. 4, 
sample 
No. ID 
Mar. 4, 
sample 
No. 12 6 
Mar. 5, 
sample 
No. 13- 
Aver¬ 
age 
Sept. 24, 
sample 
No. lit 
Sept. 24, 
sample 
No. 12» 
^ Sept. 22, 
sample 
No. 13 c 
Aver¬ 
age 
Moisture equivalent... 
Feet 
1 
11.6 
25.8 
33.0 
23.5 
18.6 
27.7 
35.0 
27.1 
2 
21.5 
29.4 
29.8 
26.9 
21.9 
31.8 
30.4 
28.0 
3 
4.9 
25.0 
32.2 
20.7 
11.6 
17.7 
30.0 
19.8 
4 
20.2 
21.7 
34.1 
25.3 
20.2 
24.3 
27.3 
23.9 
Wilting coefficient. 
1 
6.3 
14.0 
17.9 
12.7 
10.1 
15.1 
19.0 
14.7 
2 
11.7 
16.0 
16.2 
14.6 
11.9 
17.3 
16.5 
15.2 
3 
2.7 
13.6 
17.5 
11.3 
6.3 
9.6 
16.3 
10.7 
4 
11.0 
11.8 
18.5 
13.8 
11.0 
13.2 
14.8 
13.0 
Moisture content above or 
1 
+2.9 
+7.2 
+6.9 
+5.7 
-6.6 
-13.7 
-12.1 
-10.8 
below wilting coefficient. 
2 
+7.4 
+8.5 
+8.7 
+8.2 
-0.8 
-12.1 
-4.3 
-5.7 
3 
+1.6 
+1.0 
+10.0 
+4.2 
+0.4 
-3.8 
+3.6 
+0.1 
4 
+0.3 
-4.0 
+10.5 
+2.3 
-1.3 
-7.3 
+10.3 
+0.6 
Salt content. 
1 
.32 
.16 
>2.50 
.99 
.58 
.18 
>2.50 
1.09 
2 
.32 
.60 
1.16 
.69 
1.16 
.94 
1.04 
1.05 
3 
.66 
.52 
.32 
.50 
1.13 
.67 
1.04 
.95 
4 i 
1.58 
.52 
.26 
.78 
1.40 
.58 
.27 
.75 
° All data in this table are stated in percentages of the dry weight of the soil. 
b Poor growth. 
e Rank growth. 
Table XXVII. — A comparison of the spring and fall soil conditions at the same 
station on seepweed areas a 
Item 
Depth 
of 
soU 
Chandler, Ariz., 
1915. Date of 
collection 
Casa 
Grande* 
Ariz. 
Date of 
collec¬ 
tion 
Oct. 11, 
1915, 
sample 
No. 10 * 
Mar. 25, 
sample 
No. 14 * 
Oct. 7, 
sample 
No. 14 * 
Feet 
Moisture equivalent-.-. 
1 
5.4 
5.5 
16.0 
2 
14.7 
16.6 
16.1 
3 
14.9 
20.2 
16.0 
4 
18.4 
21.3 
18.2 
Wilting coefficient -.. 
1 
2.9 
3.0 
8.7 
2 
8.0 
9.0 
8.7 
3 
8.1 
11.0 
8.7 
4 
10.0 
11.6 
9.9 
Moisture content above or below wilting coefficient. 
1 
+1.9 
-1.9 
dc 
2 
+5.6 
-0.6 
sm 
3 
+4 0 
+2.1 
sm 
4 
+6.1 
+2.1 
sm 
Salt content. 
1 
.02 
.33 
.25 
2 
.14 
.94 
.50 
3 
.54 
1.16 
1.04 
4 
1.56 
1.46 
.70 
0 All data in this table are stated in percentages of the dry weight of the soil. 
b Boring No. 14 was made in an area where seepweed was mixed with narrowleaf saltbush and mesquite.. 
Boring No. 10 was made in a typical area of seepweed. 
c d=dry soil; sm=slightly moist soil. 
