112 
Journal of Agricultural Research 
Vol. XXVIII, No. 2 
and southeastern California, where the mean annual rainfall is less than 10 inches. 
This type is nonagricultural unless irrigated. Neither creosote bush nor bur- 
sage has any grazing value. In wet years, however, annuals appear on the 
range occupied by this type which afford a limited amount of feed for stock. It 
has a carrying capacity of 0 to 10 head of cattle per section. 
(71) Encelia ( Encelia farinosa A. Gray) and California Sagebrush 
(. Artemisia californica Less.).—This is a very common type in the dry inland 
valleys of California. It consists of a shrubby growth of Encelia farinosa , a 
rather coarse-stemmed plant with sunflowerlike flowers bearing rigid, white, 
and light-colored leaves; and Artemisia calif ornica, a plant of similar size with 
very finely divided leaves and darker appearance. These shrubs have no value 
for grazing and the lands they occupy have no value for crop production, unless 
irrigated. 
(72) Shrub Buckwheat (Eriogonum fasciculatum Benth.).—Shrub buckwheat 
is the dominant species in this type. It also contains scattering plants of Joshua 
tree ( Yucca arborescens). With this type are often mixed a large number of 
shrub plants and occasionally juniper and creosotebush. This type is found in 
the desert regions of southeastern California and southern Nevada; its agricul¬ 
tural and grazing value are similar to the preceding type. 
(73) Desert Brush Type: Creosotebush, Iron wood (Olneya tesota A. 
Gray), Mesquite, Paloverde ( Parkinsonia microphylla Torr.), and Catsclaw 
(Acacia greggii A. Gray).—This is a mixed desert brush type in which creosote¬ 
bush, mesquite, paloverde, iron wood, and catsclaw are the five important species. 
It is common in the desert region occupying large portions of western Arizona and 
southeastern California. It usually occurs along drainage channels. The 
aridity of the region where this type is found precludes the possibility of produc¬ 
ing crops without irrigation. Mesquite and paloverde are the only species 
that have any appreciable grazing value. It has a carrying capacity of less than 
10 head of cattle per section. 
(74) Creosotebush-Desert Grass. —A typical creosotebush-desert grass 
area is illustrated by Plate 13, A. It is composed of a scattered growth of 
creosotebush over grass land consisting usually of Bouteloua rothrockii , Bouteloua 
eriopoda , and Hilaria mutica . This type grows on loamy soils in southern New 
Mexico and Arizona. With the exception of Hilaria mutica , all the grasses 
growing in this type are highly palatable. It has a carrying capacity of 10 to 
20 head of cattle per section. The land producing these species is too arid to 
grow crops unless irrigated. 
(75) Creosotebush and Cacti (Opuntia species.)—This type grows in 
rather broken or rocky areas in southern New Mexico and the desert regions of 
Arizona, southern Nevada, and southeastern California. It is made up of a 
scattered growth of creosote bush and an abundance of cacti, especially the barrel 
cactus which varies in diameter from 1 to 1| feet, and in height from 2 to 4 feet; 
and the round-stemmed Opuntias, especially the dense spiny Opuntia bigelovii . 
It is nonagricultural unless irrigated and of little or no value for grazing. 
(76) Creosotebush-Ocotillo ■ (Fouquieria splendens Engelm.)—The creo- 
sotebush-ocotillo type, which comprises a scattered growth of creosotebush and 
ocotillo, and many other plants of less conspicuous nature, occupies rocky and 
gravelly soils. It is widely distributed in the desert areas from southeastern 
California to western Texas. Both of the dominant species in this type are 
unpalatable to stock and the rocky nature of the habitat precludes the produc¬ 
tion of annuals. Lands producing this type are therefore nonagricultural and 
have a very low carrying capacity. 
( 77 ) Giant Cactus ( Carnegiea gigantea (Engelm.) Britton & Rose), and 
Bur-sage. —Giant cactus and bur-sage are the dominant species in this type. 
