BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Cercocarpus betuloides | Birchleaf Mountain-Mahogany 



GENERAL BOTANICAL CHARACTERISTICS : 
Birchleaf mountain-mahogany is an erect, open shrub or small tree.
Plants are typically 5 to 12 feet (1.5-3.6 m) tall but occasionally grow
up to 20 feet (6 m) [42].  Birchleaf mountain-mahogany height varied as
follows in different aged chaparral stands in southern California [17]:

                   coastal chaparral          desert chaparral   
                   (feet)   (meters)          (feet)  (meters)
Stand age
2-8 years           5.2       1.6              4.6       1.4
9-21 years          5.2       1.6              7.8       2.4
22-40 years         6.6       2.0              7.5       2.3
40+ years           7.2       2.2              9.1       2.7

Mature birchleaf mountain-mahogany plants typically have considerable
amounts of dead branches [14].  Simple, alternate, wedge-shaped leaves,
up to 1 inch (2.5 cm) long, are borne on spurlike branchlets [37].  Bark
is smooth and gray.  The fruit is a soft, hairy, tubular achene with a
2- to 3-inch-long (5-7.5 cm) feathery style at the tip [10].


RAUNKIAER LIFE FORM : 
   Microphanerophyte
   Nanophanerophyte


REGENERATION PROCESSES : 
Birchleaf mountain-mahogany begins producing seed at about 10 years of
age.  Seed crops vary from very light to very heavy [3].  The seeds are
not dormant and germinate readily without pretreatments.  The fruit and
awned-seeds are dispersed widely by wind, and occasionally by animals
[10].  Seedling establishment is infrequent and is probably substantial
only in years of high precipitation.

Birchleaf mountain-mahogany sprouts vigorously from the root crown after
top-killing disturbances [3].


SITE CHARACTERISTICS : 
Birchleaf mountain-mahogany occupies dry foothills and lower mountain
slopes and ridges [9,21,42].  It is most abundant in chaparral
vegetation types but is also common at its upper elevational limits in
the understory of pinyon-juniper (Pinus edulis, P. monophylla-Juniperus
spp.), oak (Quercus wislizeni, Q. chrysolepis), and pine (Pinus
ponderosa, P. sabiniana) woodlands [7,9,35].

In southern California, birchleaf mountain-mahogany occurs in both
coastal (west of the mountain range crest) and desert chaparral stands
(east of the crest) but generally makes up a greater percentage of the
cover in desert chaparral.  It is often associated with north-facing
aspects.  On coastal exposures it becomes more abundant with increasing
elevation [17].  Elevational range is 3,000 to 6,500 feet (915-1,982 m)
in Arizona, and 500 to 6,000 (152-1,829 m) in California [7,9].


SUCCESSIONAL STATUS : 
Birchleaf mountain-mahogany is a stable member of chaparral communities.
The plant is a long-lived vigorous sprouter and neither a regime of
frequent fires nor long fire-free periods will eliminate it.  During
long, fire-free intervals, birchleaf mountain-mahogany rejuvenates its
canopy by resprouting, ensuring continuous recruitment of new stems from
an established root crown [23].  Under a regime of frequent fires,
postfire sprouting ensures little demographic change [18].  In Arizona,
shrub live oak-birchleaf mountain-mahogany communities are considered
climax types [8].

Burcham [6] reported that in certain situations in southern California,
pinyon-juniper communities may be replaced by birchleaf
mountain-mahogany and desert ceanothus following fire.


SEASONAL DEVELOPMENT : 
Birchleaf mountain-mahogany has been variously described as evergreen,
deciduous, and partly deciduous.  In some areas it apparently loses 25
to 75 percent of its leaves each fall [3].  Flowering in California is
from March to May [9], and in Arizona from March to July [21].

Related categories for Species: Cercocarpus betuloides | Birchleaf Mountain-Mahogany