IMPORTANT WESTERN BROWSE PLANTS 113: 
species of western Texas, forming junglelike growths, is limitedly 
browsed. . 
In western Texas occurs one, or possibly two, species of coyotillo 
(iXarwinskia). In 1891 Coulter (24) mentioned a report that the 
brownish-black berries of H. humboldtiana, sometimes called cajo- 
tillo cr margareta, are poisonous; Pammel later (95) quotes A. 
Mitchell of the Third U. 8. Cavalry to the effect that this bush is 
poisonous to goats. Marsh, Clawson, and Roe (85, 87) have recently 
found that the leaves are only shghtly poisonous and the pulp of 
the fruit not at all, but that the seeds are highly toxic and affect 
all domestic animals. 
BUCKTHORNS (RHAMNUS SPP.) 
This genus is represented in the West by about 14 valid species 
but has little forage significance. Certain species (notably common 
buckthorn of the Old World, 7. cathartica, often cultivated in this 
country and which has escaped and become naturalized in many 
localities) harbor the aecidia of crown rust (Puccinia coronate) and 
have caused epidemics of that disease in oats (3/, 32). 
Cascara buckthorn (2. purshiana), also called cascara (131), and 
locally known as cascara sagrada, chittim, coffee berry, mountain 
cranberry, pigeon berry, and shittimwood, ranges from British 
Columbia to western Montana and northern California and is by 
far the most important species economically, being the source of 
the medicinal cascara sagrada (sacred bark). Cascara buckthorn 
is cropped a little by sheep, but is almost negligible as a browse and 
frequently is out of reach of livestock. 
Alder buckthorn (7. alnifolia) and California buckthorn (/. 
californica), of California, often known as pigeon berry, are two 
very widely distributed shrubs that furnish poor to fair sheep browse 
but are virtually worthless for cattle; the berries of the latter are 
edible and are much relished by birds. Some of the thick, ever- 
ereen-leaved species have a very limited browse utility on late fall, 
winter, and early spring range. 
Sageretia wrightii is a spiny-twigged Mexican shrub reaching 
into the Southwestern States from western Texas to southeastern 
Arizona. The juicy edible berrylike fruits give it some wild-life 
interest; but though it deserves further study it has, so far as now 
known, no forage importance. ; 
JUJUBES (ZIZYPHUS SPP.) 
This genus is represented in the Southwest by four shrubby na- 
tive species, as well as the Old World common jujube (2. jujuba, 
syns. Z. vulgaris and Z. sativa), cultivated for its edible fruits, 
which has become naturalized in parts of the southern United States. 
Southwestern jujube (Z. lycioides, syn. Condalia lycioides), 
known locally as whitethorn and by a variety of Mexican names 
including barchatas, crucillo, garambullo, and paloblanco, 1s the 
most widely distributed and best known of these native species. 
Tt occurs from western Texas to southeastern California and south 
into Mexico, often in the hoary-leaved variety canescens. It in- 
habits both dry and moist sites from the covillea-mesquite belt to’ 
27258°—31——_8 
