158 MISC. PUBLICATION 101, U. S. DEPT. OF AGRICULTURE 
rocky hillsides, is commonly regarded by sheepmen adjacent to the 
Medicine Bow Forest, Wyo., as poisonous. 
BACCHARISES AND CONGENERS (BACCHARIS SPP.) 
Baccharis is a very large (chiefly South American and Mexican) 
genus, mainly more or less shrubby, and with the sexes distinct 
(diecious). Of the 23 species growing naturally in the United 
States 16 occur in the far West, chiefly in California and the South- 
west. The forage value is worthless or poor and some of the species 
are known to be poisonous. ‘The coastal mio mio, or nio nio (8B. 
coridifolia) of Atlantic South America contains baccharin, an alka- 
loid toxic to sheep (744, 95), and Girola (43) states that it causes 
fatal poisoning to cattle, sheep, goats, and rabbits and that B. amig- 
dalina is a suspected species in Argentina. 
Yerba-de-pasmo (BL. ramulosa, syn. B. pteronioides) is a low resin- 
ous shrub (fig. 40), 10 to 86 inches high, ranging from western 
Texas to southern Arizona and south into Mexico. The vernacular 
name alludes to the common use by Indians and Mexicans of an 
infusion of the leaves as a remedy for chills. It is also frequently 
known as burroweed, chamisa, chill weed, and winged baccharis. It 
occurs abundantly but mostly scatteringly on dry, gravelly foothills 
and plains, chiefly between 3,900 and 6,500 feet, but is occasionally 
found up to nearly 8,000 feet and usually grows in grass-weed or 
open oak-brush, covillea, or mountain-mahogany types. Ordinarily 
the plant is not more than nibbled except on overgrazed or over- 
stocked range when it sometimes causes trouble. C. Dwight Marsh, 
of the Bureau of Animal Industry, regards this species as probably 
responsible for serious cattle losses sustained in 1918 and later on 
the Coronado (Chiricahua) National Forest, Ariz., and the Lincoln 
Forest, N. Mex., and he states (87) that experimental work has 
definitely demonstrated that the species is poisonous to sheep, the 
poisoning taking place in late fall to midwinter. 
Emory baccharis (2. emory?), locally known as water moats and 
water willow, is a shrub, 3 to 12 feet high, ranging from Colorado 
to California and New Mexico, usually along washes and in coastal or 
inland flood plains but sometimes in drier, gravelly rocky or clayey — 4 
soils in open sagebrush-shadscale, juniper, or weed-grass types, often 
being abundant and well distributed between sea level and 5,500 
feet. As a rule it is worthless or else but slightly browsed, but in 
parts of southeastern Arizona it is appreciably grazed by both cattle 
and horses from May to December. 
Seepwillow (BL. glutinosa), locally named false, Gila, or water 
willow, groundsel tree, water motie, and water-wally, is a bush— 
occasionally only half-shrubby—3 to 12 feet high, with viscid willow- 
hike leaves, and has an enormous distribution from western Texas to 
Colorado and southern California and south, through Mexico and 
Central America, to Chile. It is typically a riparian species, grow- 
ing in scattered clumps or in extensive dense thickets along streams, 
lake margins, in alluvial plains, canyons, or other moist situations; 
in such places it is frequently dominant. As a forage plant it is 
worthless or very poor, but has considerable value in erosion control 
because of the abundant, tenacious, and both deep and widespreading 
roots. 
