760 
Journal of Agricultural Research 
Vol. XXVIII, No 8 
Torr., Dondia intermedia (S. Wats.) Heller and Lycium parviflorum A. Gray are 
scattered throughout the area. In places the annual Atriplex fasdculata S. Wats, 
is abundant after the summer rains. 
APPEARANCE 
At a distance narrowleaf saltbush areas are hard to separate from those of 
desert-sage. At closer range the narrowleaf saltbush appears much smaller and 
lighter colored, but it has larger leaves than the desert-sage and more of them are 
retained so that less of the dark stems show. 
PHYSICAL CONDITIONS INDICATED 
Soil Moisture 
Narrowleaf saltbush indicates a hard compacted red soil at from 4 to 18 inches 
below the surface. The soil above is loose and lighter. In fall all 4 feet were 
dry with no moisture available. There are indications that water collects in these 
areas after the rains so that at this time there is a good supply of available moist¬ 
ure, at least in the upper lighter soil. 
Salinity 
The salt content of the lighter layer above the red compacted soil is not very 
high (Table XV), but that of the compacted subsoil is considerably higher. 
Where narrowleaf saltbush mixes with creosote bush the salt content is much 
lower (Table XVI). 
Summary of Physical Conditions Indicated 
Typical areas of narrowleaf saltbush indicate: (1) A heavy compacted subsoil 
with a lighter layer of soil 4 to 18 inches in depth; (2) no available moisture in the 
fall in any of the 4 feet of soil but probably a good supply in the upper, light 
layer of soil after the rainy season; (3) a small quantity of salts in the light layer 
of soil but ranging over % per cent in the compact subsoil. Narrowleaf salt¬ 
bush indicates a much shallower soil than desert-sage. 
Table XV.— Soil conditions in typical areas of narrowleaf saltbush , Casa Grande , 
1915 « 
Item 
Depth 
of 
soil 
Date of collection 
Average 
Oct. 11 
sample 
No. 3 * * * * 6 
Oct. 12 
sample 
No. 15 
21.9 
21.4 
21.7 
21.4 
25.6 
23.5 
18.3 
22.5 
20.4 
20.4 
31.3 
25.8 
11.9 
11.6 
11.8 
11.6 
13.9 
12.8 
9.9 
12.2 
11.1 
11.1 
17.0 
14.1 
d 
cd 
d 
d 
d 
d 
d 
d 
.15 
.17 
.16 
.34 
.24 
.29 
.22 
.98 
.60 
.25 
.91 
.58 
Feet 
Moisture equivalent. 
Wilting coefficient. 
Moisture content above or below wilting 
coefficient... 
Salt content. 
a All data in percentages of the dry weight of the soil. A m 
6 Sample No. 3 was taken in a narrowleaf saltbush flat surrounded by creosote bush. See Table XVI 
for sample taken where narrowleaf saltbush and creosote bush mix at the border line of this same flat. Sam¬ 
ple No. 15 was taken in a narrowleaf saltbush flat surrounded by desert-sage, 
e d=dry soil. 
