8 MISC. PUBLICATION 101, U. S. DEPT. OF AGRICULTURE 
families, the mimosa, or sensitiveplant (Mimosaceae), cassia, or senna 
(Caesalpinaceae), and ratany (Krameriaceae), all of which are of 
interest on the western range, the mimosa having great browse im- 
portance, in the Southwest particularly. To the mimosa family 
belong catclaw, or acacia (Acacia), silk flower, or_false-mesquite 
(Calliandra), sensitiveplant (Mimosa), mesquite (Prosopis), and 
screwbean, or tornillo (Strombocarpa). The well-known Jerusalem- 
thorn (Parkinsonia) and paloverdes (Cercidium) of the South and 
Southwest belong to the cassia family, or subfamily. 
The largest of all plant families, the composites (Compositae or 
Asteraceae) does not, aside from the large sagebrush genus (Arte- 
misia), produce in the West any considerable number of palatable 
browse species, two or three woody groundsels (Senecio), about as 
many species of rabbit brush (Chrysothamnus), encelia, carpho- 
chaete, a woody viguiera, and possibly a few others being of value 
in certain localities. These composites are, in general, characteristic 
of the drier, lower, open and sunny ranges, and are of most impor- 
tance for grazing in the plains, Great Basin, and southwestern 
regions or on winter ranges or at times when other feed is short. 
Some of these species, however, have such enormously wide distri- 
bution and abundance that the big percentage of the range vegeta- 
tion occupied by them counteracts in large measure their more lim- 
ited palatability per plant. Some of the sagebrushes seem to possess 
tonic properties—probably related chemically to the peculiar bitter 
taste of their herbage—that enhance their attractiveness to livestock, 
especially at certain seasons. ‘The toxic qualities of this family 
(Compositae) are attracting attention increasingly because of the 
various cases of range poisoning that have been demonstrated to be 
due to certain shrubby genera, such as baccharis, rabbit brush, 
snakeweed (Gutierrezia), rayless goldenrod, or “jimmy-weed ” 
(Aplopappus=Isocoma), Tetradymia, and woody aster (Aster= 
Xylorrhiza). Over 20 shrubby genera of composites are com- 
monly represented on western ranges, in addition to at least three 
genera, bur-sage or bur-ragweed (Franseria), burrobrush (Hy- 
menoclea), and Oxytenia—all more or less shrubby and rather or 
quite worthless as forage—belonging to the ragweed family (Ambro- 
siaceae), subfamily, or tribe included in the composites by many 
authors. No shrubby members of the chicory-dandelion group 
(Cichorieae or Cichoriaceae), which produces numerous valuable 
herbaceous forage plants, occur in the United States, unless a few 
worthless, undershrubby skeletonplants (Lygodesmia spp.) be placed 
in this category. 
One of the most valuable groups of western browse plants, espe- 
cially in the plains and Great Basin regions and in soils more or 
less impregnated with alkali and saline matter, is the goosefoot 
family (Chenopodiaceae). Here are found such familiar shrubs 
as the saltbushes and shadscales (Atriplex spp.), winter fat or white 
sage (Eurotia), greasewood (Sarcobatus), and hop-sage (Grayia). 
The salty taste of the herbage of these plants seems to be very agree- 
able to stock. 
The buckthorn family (Rhamnaceae) is of grazing interest almost 
solely because of one genus, but a very important one, Ceanothus. 
