BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Chrysolepis sempervirens | Bush Chinquapin 



GENERAL BOTANICAL CHARACTERISTICS : 
Bush chinquapin is a monecious, native, evergreen, schlerophyllous
shrub.  It may grow up to 8 feet (2.5 m) tall [9] but is typically from
1 to 5 feet (0.3-1.5 m) in height [22].  Plants have a prostrate to
spreading, round-topped growth form [9].  Male catkins are produced from
the tips of terminal and side branches [26].  One to three female
flowers grow at the base of the male catkins or on short separate
catkins [9,24].  The fruit is a nut with a woody seed coat enveloped by
a densely burred involucre [9,26,32].  Nuts contain from one to three
seeds, usually one [33].  No information concerning the bark thickness
or rooting habit of bush chinquapin is available.


RAUNKIAER LIFE FORM : 
   Phanerophyte


REGENERATION PROCESSES : 
Chinquapins are wind pollinated [29].  The age of sexual maturity and
maximum seed production are not reported in the literature.  Most seed
falls under the parent.  Some seed may be disseminated by animals when
the nut burs catch on furs or hides.  Other seed is dissemminated by
seed-eating birds and rodents [30].  Seed predation is high [24].  Some
seed is probably buried by seed-caching animals, and unconsumed seed so
buried may have higher rates of germination.  Germination is hypogeal
and occurs from 16 to 25 days after nuts split and release seed.  Cold
stratification does not increase germination rates.  Investigations of
fresh seed viability are scant, but one study showed 30 percent
germination of seeds 25 days following sowing.  Chinquapins seeds has
remained viable for 5 years with cold, dry laboratory storage [24].
Research on the long-term viability of seed in seed banks is lacking.


SITE CHARACTERISTICS : 
Bush chinquapin grows on steep, often south-facing slopes within the
coniferous forest zone [22,23,43].  It is also found on the more gentle
slopes of that zone where disturbance has removed the original forest
cover [23].  Low-growing forms of this shrub occur above timberline and
can be found on Sonora, Tioga, and Carson passes [39].  Bush chinquapin
occurs as high as 12,000 feet (3,658 m) [26] but is most common from
1,500 to 6,000 feet (459-1,829 m) in elevation [22].

The climate of montane chaparral is dry in summer, with precipitation
usually plentiful from October until May.  Some precipitation is in the
form of snow.  One 5,500-foot (1,676 m) site on the Shasta-Trinity
National Forest, California, receives an average of 38 inches (985 mm)
of annual precipitation, half as snow [6].  Soil conditions are
generally the same as those of adjacent coniferous forests [18].

Overstory associates not listed in Distribution and Occurrence include
sequoia, sugar pine (Pinus lambertiana), incense-cedar (Libocedrus
decurrens), Sierra western juniper (Juniperus occidentalis var.
australis), Pacific yew (Taxus brevifolia), bigleaf maple (Acer
macrophyllum), and Pacific dogwood (Curnus nuttallii) [2,12,19,34,35].

Shrub associates not previously mentioned include Sierra mountain
misery, pinemat manzanita (Arctoshaphylos nevadensis), Saskatoon
serviceberry (Amelanchier alnifolia), sharpleaf snowberry
(Symphoricarpos mollis), Parish snowberry (S. parishii), huckleberry oak
(Quercus vaccinifolia), and bitter cherry (Prunus emarginata)
[2,8,19,34,43].

Herbaceous associates include bracken fern (Pteridium aquilinum),
feather Solomon's-seal (Smilacina racemosa), rockcress (Arabis
platysperma), Penstemon spp., fleabane (Erigeron breweri), and goosefoot
violet (Viola purpurea).  Grass associates are few but include crested
stipa (Stipa coronata var. depauperata), California needlegrass (S.
californica), bluebunch wheatgrass, and bottlebrush squirreltail (Elymus
elymoides) [2,31,34,35,41].


SUCCESSIONAL STATUS : 
Facultative Seral Species

Montane chaparral is seral to various coniferous forests [4].  Bush
chinquapin is an enhanced survivor in these early- to mid-seral
communities.  Its cover is greatest in the late mid-seral stage, when
tree canopy begins to close [8].  Bush chinquapin is moderately shade
tolerant and grows in the lower strata of near-climax open coniferous
forests.  When fire is excluded from coniferous forests for long periods
of time, bush chinquapin is shaded out [19,43].

Montane chaparral represents a topographic or edaphic climax on some
sites, such as steep, south-facing slopes or areas with shallow rocky
soil.  Bush chinquapin is considered part of climax vegetation on such
sites [22,23,43].


SEASONAL DEVELOPMENT : 
Plants flower continuously from July through September in most of their
range [9,33].  Bush chinquapin on the western edge of the Great Basin
bloom from June until the onset of winter [32].  Seed ripens in the late
summer or early fall of the second year of development [9,24,26,32].
Nuts open in mid-fall [25,26].    

Related categories for Species: Chrysolepis sempervirens | Bush Chinquapin