BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Abies procera | Noble Fir 



GENERAL BOTANICAL CHARACTERISTICS : 
Noble fir is a native, long-lived conifer [1,17,46].  It usually lives
up to 400 years, with a maximum of 600 to 700 years [1,15,19].  Mature
noble fir can reach 230 feet (70 m) in height and 45 to 60 inches
(114-152 cm) in d.b.h. [15,18,19,31].

The trunk is self-pruning and pillarlike [1].  The crown is often open
and dome-shaped with short, horizontal branches [1].  The bark of young
noble fir is thin but becomes thick with age [22,31].  Cones are erect
and generally 11 to 18 inches long [1,22,31].


RAUNKIAER LIFE FORM : 
   Phanerophyte


REGENERATION PROCESSES : 
Noble fir begins producing seed at 25 to 30 years of age, but
large-volume crops are not produced until age 35 to 50 [14,17,45].  Good
seed crops are produced at 3- to 6-year intervals [7,14,17,45].

Seed quality is often poor [18].  Cone crops need to be medium size or
better for sound seed to exceed 10 percent [17].  Cone and seed
collection, drying, and storage techniques are discussed in the
literature [7].  Insects that cause some losses are also discussed [45].
Seeds are disseminated by wind.  Seeds can be dispersed up to 2,000 feet
(367 m) from the source, but most fall within one or two tree height of
the parent [7,17].

Seeds usually germinate in the spring after they are shed [1,19].  Seeds
remain viable for only 1 year.  A mineral seedbed in relatively open
areas is favorable for seedling establishment and growth [22].
Competing vegetation and frosts deter regeneration of noble fir [18].

As with other firs, initial juvenile growth is slow [16,17,27].  Noble
fir requires 5 to 12 years to reach breast height, depending on site
condition [16,18,27].  Growth from a sapling stage to maturity is rapid,
allowing noble fir to attain site dominance [27,43].  As the tree ages,
growth slows [27].  Where they occur together, noble fir growth exceeds
Douglas-fir after 100 years [24].

Noble fir does not reproduce vegetatively [18].


SITE CHARACTERISTICS : 
Noble fir occurs in a maritime climate with cool summers and mild, wet
winters [17,18,25].  Annual precipitation is between 72 and 106 inches
(1,960-2,650 mm) [18,25].  Most of the precipitation occurs between
October and March, resulting in snowpacks of 3 to 10 feet (1-3 m)
[17,18].  The growing season in the Pacific silver fir zone averages 40
to 50 days [26].

Noble fir grows well on a variety of sites.  It occurs on steep slopes
but grows best on gentle slopes and warm southern aspects [17,18,25].
Shallow or moderately deep loams support good growth [28].  Inceptisols
and Spodosols are common.  Soils are typically developed in volcanic
parent materials [18,25,47].  Water supply is apparently more important
than soil quality [17,18,24].
  
In the northern Cascades, noble fir is most common between 3,000 and
5,500 feet (900-1,650 m) in elevation.  It can occur below 2,500 feet
(706 m) but is sparse [12,17,36].  Farther south near Crater Lake
National Park, Oregon, noble fir occurs from 5,500 to 8,000 feet
(1,670-2,425 m) [1].

Canopy associates not listed in Distribution and Occurrence are western
larch (Larix occidentalis), Brewer spruce (Picea breweriana), and
Alaska-cedar (Chamaecyparis nootkatensis) [2,9,18,20,39].  Understory
associates include huckleberries (Vaccinium spp.), vine maple (Acer
circinatum), devil's club (Oplopanax horridum), beargrass (Xerophyllum
tenax), dogwood bunchberry (Cornus canadensis), coolwort foamflower
(Tiarella unifoliata), vanillaleaf (Achlys triphylla), queencup beadlily
(Clintonia uniflora), and fairybells (Disporum hookeri) [4,9,20,28,47].


SUCCESSIONAL STATUS : 
Facultative Seral Species

Noble fir is a seral or pioneer species [18].  It is the most shade
intolerant of the American true firs [18] and cannot regenerate under a
closed forest canopy [1,17,18].  Noble fir often establishes with
Douglas-fir [4,9,15,17,19].  It establishes after disturbances such as
wildfire that create major stand openings [17,22].  Even-aged stands are
common [13,43].  Noble fir is classified as intermediate in shade
tolerance.  Overtopped seedlings of noble fir occasionally persist, and
in the Oregon Coast Ranges, seedlings sometimes establish in partial
shade [18].  Noble fir is eventually replaced by shade-tolerant species
such as Pacific silver fir and western hemlock [9,17,22].


SEASONAL DEVELOPMENT : 
Male and female bud burst occurs in May and early June, and is followed
by pollen shed in June and early July [14,18,21,45].  Pollen shedding
and female receptivity are well synchronized in noble fir [21,45].
Cones ripen in mid- to late September, and seed dispersal begins in
early October [14,21,45]. Seed dissemination requires wind action or
other branch movement to disturb the cone [7,21].  Height growth is
greatest in July [27].

Related categories for Species: Abies procera | Noble Fir