BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Abies magnifica | California Red Fir 



GENERAL BOTANICAL CHARACTERISTICS : 
California red fir is a native, long-lived conifer that ranges between
66 and 198 feet (20-60 m) in height [26,32,45,49,70].  Mature trees can
grow to a d.b.h. of 8.5 feet (2.6 m) [1].  The bark of young trees is
thin but becomes thick and roughly fissured with age [12,45,49].  The
needles are 0.8 to 1.4 inches (2.0-3.5 cm) long [49].  Cones are upright
on the upper branches and are up to 9 inches (23 cm) long [43,45].
California red fir has short branches and a narrow crown [35,49].

California red fir has a high frost tolerance.  California red and
Shasta red fir have a low drought tolerance [23,34,44].
  


RAUNKIAER LIFE FORM : 
   Phanerophyte


REGENERATION PROCESSES : 
California red fir does not reproduce vegetatively [43].

The minimum seed-bearing age for California red fir is 35 to 45 years of
age and 30 to 40 for Shasta red fir [17,26,43].  Good seed crops are
produced at 2- to 6-year intervals [17,26,28,44].  Seed is disseminated
by wind a distance of approximately 1 to 1.5 tree heights from the
parent [43,44].  The average germination rate of California red fir
seeds is 30 to 43 percent [28,43,44].  Insects account for 18 to 45
percent of annual seed loss [64].

Initial seedling establishment is best in bare mineral soil or light
litter [5,,24,41,44].  Seeds of California red fir usually germinate the
first spring after they are shed and are not stored in the forest floor
[31].  After the first year, seedling survival was higher in seedbeds
with heavier litter than those seedbeds without litter [30].
Competition and shading from shrubs and grasses and frost damage inhibit
establishment and growth of California red fir [24,30,67].  Seedlings
near stand edges had lower survival rates than those farther away from
the edge [30].

Mortality is greatest soon after the tree reaches 12 inches (30 cm) in
height and is usually attributed to pocket gophers damaging seedling
roots and deer clipping new foliage [31].

Initial growth is best in dense shade with medium litter on the soil,
but when seedlings get older, growth is best in full sunlight
[19,30,43].  Initial growth of California red fir seedlings is slow, 4
to 6 inches (10-15 cm) in the first 2 to 4 years [5,24,54].  Laacke [43]
stated that the long-standing assumption of slow growth for the first 20
to 30 years may be invalid.  It can take between 10 and 25 years for
California red fir to reach breast height [32].  Following the initial
slow juvenile growth stage is a fairly long period of rapid growth and,
eventually, an extended period of slower growth [32].  Saplings greater
than 10 years of age reach full growth potential after release from
suppression [6].


SITE CHARACTERISTICS : 
California red fir grows best in areas with cold, wet winters and warm,
dry summers [45,50,54].  The growing season is short, with snow often on
the ground in July [6,7,35,48].  Annual precipitation ranges from 33 to
64 inches (820-1,600 mm), most of which occurs between October and March
as snow [6,7,43,54].  Snowpack is usually between 8 and 13 feet (2.5-4
m) [6,54].

California red fir commonly grows on soils with a pH range of 5.0 to 6.1
[50].  It occurs on deep sandy loams and shallower soils of moraines
[5].  California red fir will sometimes grow on nutrient-poor Entisols
or Inceptisols but usually grows on soils that are more nutrient-rich,
coarse, and well-drained but moist [7,35,65].  California red fir is
sensitive to poorly drained soils [44].  Shasta red fir is more common
on northern aspects but occurs equally on all slopes [4].

Shasta red fir occupies the elevational zone below mountain hemlock and
above white fir [1,3,24,27].  The elevations at which California red fir
occurs in different parts of its range are listed below [6,43,44,50]:

Location                          feet              meters
Klamath and Coast ranges       4,500-5,500        1,370-1,675
Siskiyou Mountains
  and southern Cascade Range   4,590-5,900        1,400-1,800
northern Sierra Nevada         5,940-7,920        1,800-2,400
southern Sierra Nevada         7,000-9,000        2,200-3,000

Canopy associates of California or Shasta red fir not mentioned in
Distribution and Occurrence are giant sequoia (Sequoiadendron
giganteum), Alaska-cedar (Chamaecyparis nootkatensis), sugar pine (Pinus
lambertiana), western juniper (Juniperus occidentalis), Brewer spruce
(Picea breweriana), Washoe pine (Pinus washoensis), noble fir, and
foxtail pine (Pinus balfouriana) [1,2,4,35,53].  Understory species
differ greatly in different habitats [14].  Associated shrubs include
thinleaf huckleberry (Vaccinium membranaceum), currant (Ribes spp.),
twinflower (Linnaea borealis), mountain snowberry (Symphoricarpos
oreophilius), huckleberry oak (Quercus vaccinifolia), Sadler oak
(Quercus sadleriana), and pinemat manzanita (Arctostaphylos nevadensis)
[4,43,50,55].  Associated herbaceous species include sedges (Carex
spp.), lupine (Lupinus spp.), beargrass (Xerophyllum tenax), Brewer's
goldaster (Chrysopsis breweri), lousewort (Pedicularis semibarbata),
hairstem gayophytum (Gayophytum ramosissimum), whitevein pyrola (Pyrola
picta), and monardella (Monardella spp.) [4,50,55].  Lichens (Evernia
and Vulpina spp.) also occur in California red fir forests [50].


SUCCESSIONAL STATUS : 
Obligate Climax Species

Stands of California red fir are typically even-aged [5,31,54,66].

California red fir forests are a climax vegetation type [36,43,48].  In
areas where California red fir grows under a closed canopy of lodgepole
pine, it eventually becomes the climax species [5].  Shasta red fir is a
late seral or climax community dominant, depending on its associates
[4,24,43].

In mixed conifer forests, California red fir establishes well in
openings and after disturbances [65].  Natural regeneration or seedling
or sapling release from suppression occurs in small openings created by
the death of a few trees or in large openings created by fire, insects,
or wind [5,66].  California and Shasta red fir are moderately shade
tolerant [3,8,24].



SEASONAL DEVELOPMENT : 
California red fir cones open and are pollinated in May and early June
[26,43,64].  Cones ripen in August [26,64].  Seed dispersal occurs in
mid-October when cones begin to disintegrate [30,44,64].  The large,
winged seeds are released through the fall and winter [26,45].

Shasta red fir cones open and are pollinated in mid- to late June, and
cones ripen in late September.  Seed dispersal occurs in late September
to mid-October [26,64].

Related categories for Species: Abies magnifica | California Red Fir