IMPORTANT WESTERN BROWSE PLANTS 43 
sites between 7,000 and 11,000 feet elevation. It is ranked as fairly 
good cattle browse in parts of the central Wasatch Mountains of 
Utah. 
American black currant (7: americanum), sometimes called black- 
bead currant, is one of the most widely distributed of all our native 
currants and because of its close relationship to the cultivated 
uropean black currant (2. nigrum), the most dangerous host of 
the white pine blister rust, would undoubtedly prove a menace in the 
vicinity of blister-rust infested or threatened plantations of any of 
the 5-needle pines. 
ROSE FAMILY (ROSACEAE) 
MOUNTAIN-MAHOGANIES (CERCOCARPUS SPP.) 
Cercocarpus is a genus of about 19 species, of which 5 are wholly 
confined to Mexico, the remaining 14 occurring in the Western 
States, mainly in the Southwest, the Great Basin, and California. 
Only one species (C. ledifolius) occurs as far north and west as 
Washington and none are found in any part of Canada. The 
broader-leaved species are, in the main, palatable and valuable 
browse; the group with narrow leathery leaves is distinctly inferior 
to the others from a forage viewpoint. 
Mountain-mahogany is somewhat cumbersome and none too ap- 
propriate a name for Cercocarpus, but the great weight of popular 
usage 1s overwhelmingly in its favor. Numerous other, and some- 
times quite misleading, local names for these shrubs include birch- 
leaf mahogany, blackbrush, buckbrush, deer brush, hard-tack, sweet- 
brush, and tallow bush. 
True mountain-mahogany (Cercocarpus montanus, syn. C. parvi- 
folius) is ordinarily a shrub 2 to 10 feet high, branching from a 
thick base, but in favorable sites occasionally becoming a small tree 
15 to 20 feet high or, rarely, even taller. The relatively small, 
birchlike, thickish leaves (fig. 8), broadest at the middle, and about 
one-half to 114 inches long, are more or less persistent. 
None of the other species of Cercocarpus has a wider distribution 
than does montanus. It occurs from South Dakota and Montana to 
New Mexico, northeastern California, and Oregon, on dry ridges 
and slopes, ordinarily between about 4,000 and 10,000 feet, and is 
perhaps most characteristic of the ‘tension zone,” or border line 
between the woodland and yellow pine types. It is frequently asso- 
ciated with Gambel oak, serviceberry, western yellow pine, juniper, 
manzanita, and various species of ceanothus, rabbit brush, and sage- 
brush, but is often the dominant species of the association and 
mostly occurs in a distinctly browse type. 
True mountain-mahogany is one of the most important species of 
western browse. As a rule the palatability is good or even very 
good for all classes of livestock and occasionally excellent, especially 
for goats. The palatability is usually somewhat greater for sheep 
than for cattle and proportionately greater, as a rule, in fall and 
winter than in summer. The leaves persist until late fall,’ but the 
twigs furnish palatable feed yearlong. Wide distribution and local 
ess 
® Forsling and Nelson note that about 90 per cent of the leaves of this shrub are fallen 
in Utah by Oct. 15. 
