VALUE AND USE
SPECIES: Cercocarpus montanus | True Mountain-Mahogany 



WOOD PRODUCTS VALUE : 
NO-ENTRY


IMPORTANCE TO LIVESTOCK AND WILDLIFE : 
True mountain-mahogany is good forage for all classes of browsing
animals in both summer and winter [6,15,48].  Livestock and big game
browse new growth in the spring [48].  True mountain-mahogany
constituted 56 to 92 percent of the summer diet of bighorn sheep in
Waterton Canyon, Colorado [44].  Deer and elk consume the leaves and
twigs of true mountain-mahogany in the summer and browse the twigs in
winter [48]. 


PALATABILITY : 
True mountain mahogany is highly palatable forage.  New spring foliage
is preferred by livestock and wildlife and remains palatable until late
fall [48].  The palatability of true mountain-mahogany to livestock and
wildlife is rated as follows:

                        CO      MT      UT      WY

Cattle                Good    ----    Fair    ----
Sheep                 Good    ----    Good    Good
Horses                Fair    ----    Fair    Good
Pronghorn             ----    ----    ----    Poor
Elk                   Good    ----    Good    Good
Mule deer             Good    Fair    Good    Good
Small mammals         Good    ----    Fair    Good
Small nongame birds   ----    ----    Fair    Good
Upland game birds     ----    ----    Fair    Fair
Waterfowl             ----    ----    Poor    Poor
        


NUTRITIONAL VALUE : 
True mountain-mahogany is nutritious forage.  Mineral levels in true
mountain-mahogany compare favorably with those of other forage species,
and true mountain-mahogany has a desirable calcium to phosphorus ratio
(7.5:1) [10].  Summer foliage of true mountain-mahogany in Waterton
Canyon, Colorado, contained 11.2 to 16.3 percent crude protein and 33.4
to 38.7 percent digestible organic matter [44].  In the Uintah Basin,
Utah, true mountain-mahogany leaves and twigs collected in early October
contained the following mineral concentrations in parts per million
[10]:

        Zn		  34.2
        Cu		  28.9
        Mn		  12.0
        Fe		 166.4
        Ca		5486.0
        Mg		2632.0
        Na		 386.6
        P		 731.8
        N		9048.0

True mountain-mahogany has low manganese, iron, potassium, and
phosphorus when compared to its associates.  Copper concentration is
relatively high; browsing animals would be poisoned by copper toxicity
if true mountain-mahogany were their sole diet item [10].


COVER VALUE : 
True mountain-mahogany provides cover for a wide variety of wildlife
species due to the juxtaposition of stands within forested and
nonforested communities [16].

The degree to which true mountain-mahogany provides environmental
protection during one or more seasons for wildlife species is as follows
[17]:

                        CO              UT              WY

Pronghorn             ----            ----            Good
Elk                   ----            Fair            Fair
Mule deer             ----            Good            Good
White-tailed deer     ----            Fair            Poor
Small mammals         Good            Fair            Good
Small nongame birds   Good            Fair            Good
Upland game birds     ----            Fair            Good
Waterfowl             ----            Poor            Poor
    


VALUE FOR REHABILITATION OF DISTURBED SITES : 
True mountain-mahogany can be used to improve ranges or rehabilitate
mountain shrub and pinyon-juniper communities [33,50], although it may
be difficult to establish [31].  True mountain-mahogany exhibits
relatively low seedling vigor and initial growth rates [31].

Regional seed sources should be used in revegetation work [27].  Achenes
should be collected in years when precipitation during the growing
season is average or above average [46].  The average germination rate
of seeds collected during a dry year was 33 percent; it was 80 percent
in years when precipitation was average or above average in Colorado.
Seeds from northwest-facing slopes had much higher germination rates
than those from southwest-facing slopes.  Achenes should be collected
when they are just beginning to fall naturally (September 15 to October
5 in Colorado) [46], and collection should be limited to the first seeds
detaching from the bush.  Immature and poor-quality seeds adhere to the
plant and disseminate last [33].

True mountain-mahogany seeds can be stored for a number of years.  Smith
[46] found that true mountain-mahogany seeds from Colorado could be
stored at 41 degrees Fahrenheit (5 deg C) for up to 3 years before
viability was reduced.  Stevens and others [51] stored seeds in an open,
unheated, and uncooled warehouse in Utah.  Germination rates remained at
64 percent for storage years 2 through 5.  Germination for storage year
7 was 46 percent, and by storage year 10, germination had dropped to 25
percent.  Viability was highest for true mountain-mahogany seeds stored
at either -5 to -10 degrees Fahrenheit (-20.5 to -23.3 deg C) or 36 to
44 degrees Fahrenheit (2.2-6.7 deg C) [47].

True mountain-mahogany may be seeded or transplanted.  Allison [2]
recommended seeding New Mexico rangeland at a rate of 0.9 seeds per
square foot [2].  Competing vegetation should be reduced to a practical
minimum.  Nitrogen fertilizers should not be used; they may increase use
of soil moisture to the detriment of young seedlings, increase
undesirable competition from forbs or grasses, and increase the
palatability of young plants.  True mountain-mahogany should be
transplanted in the fall.  Protection from the effects of overbrowsing
may be necessary [46].


OTHER USES AND VALUES : 
True mountain-mahogany is used in landscaping.  As a heat- and
drought-tolerant plant, it can be used for water-efficient landscaping
in arid environments [20].  It is planted as an ornamental throughout
the Southwest [49].


MANAGEMENT CONSIDERATIONS : 
Because true mountain-mahogany grows more slowly than many of its
associates, it continues to provide succulent forage after other species
become unpalatable [38].  Disturbance and browsing may promote the
health and vigor of true mountain-mahogany.  Very old, undisturbed
stands of true mountain-mahogany may become decadent, and their forage
may become less palatable or out of reach to most browsing animals [34].
Protecting true mountain-mahogany from browsing may result in growth
stagnation; 40 years of protection from browsing resulted in
significantly decreased true mountain-mahogany stem elongation in
Laramie, Wyoming [55].  In southwestern Colorado browse weight yields of
true mountain-mahogany increased when current annual growth stems were
clipped by 20 to 80 percent.  Clipping true mountain-mahogany by 60
percent resulted in maximum growth rates [45].

Related categories for Species: Cercocarpus montanus | True Mountain-Mahogany