Abies procera, noble fir
Cope, Amy B. 1993. Abies procera, noble fir. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://research.fs.usda.gov/feis/species-reviews/abipro
| Abbreviation | Common Name | Scientific Name | Classification | Status |
|---|---|---|---|---|
| Plants | ||||
| ABIPRO | noble fir | Abies procera | Life Form: Plants/Tree Kingdom: Plantae Class: Conifer Order: Pinales Family: Pinaceae Genus: Abies | Fed. Protected: No Nativity: Native Invasiveness: Noninvasive |
Taxonomy
The currently accepted scientific name of noble fir is Abies procera Rehd. [31,34]. There are no recognized varieties or subspecies.
Noble fir hybridizes readily with California red fir (Abies magnifica) [22,34]. Populations in southern Oregon and northwestern California may represent hybrid swarms between these two species [22]. Noble fir occurring south of the McKenzie River is not genetically pure [17].
Synonyms
- Abies nobilis (Dougl.) Lindl.
Other Common Names
red fir, white fir, larch
General Distribution
Noble fir occurs in the Cascade Range from Stevens Pass, Washington, south to southern Oregon and the Klamath Mountains in northern California [17,18,22,31,34]. Scattered populations occur on isolated peaks in the northern Coast Ranges of Oregon and in the Willapa Hills of southwestern Washington [17,18,34]. A few sources indicate that noble fir does not occur in the Olympic Mountains [17,22]. It is cultivated in Hawaii [50].
States
- United States: CA HI OR WA
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].
Plant Communities
Noble fir is often dominant in young, mixed stands [21]. It occurs primarily in the Pacific silver fir (Abies amabilis) zone [15,17] and less frequently in the western hemlock (Tsuga heterophylla) and mountain hemlock (T. mertensiana) zones [17,19]. Noble fir occurs with Douglas-fir (Pseudotsuga menziesii) and replaces it in the upper half of the Pacific silver fir zone [15]. Occasionally, noble fir occurs in small pure stands [17].
Noble fir is listed as a minor or associated species in the publications listed below:
- Plant association and management guide for the Pacific silver fir zone, Gifford Pinchot National Forest [4]
- Natural vegetation of Oregon and Washington [15]
- The forest communities of Mount Rainier National Park [20]
- Plant association and management guide for the Pacific silver fir zone, Mt. Hood and Willamette National Forests [28]
- Plant association and management guide, Suislaw National forest [29]
- Terrestrial natural communities of California [32]
- Montane and subalpine vegetation of the Klamath Mountains [39]
Canopy associates not listed in table A1 include western larch (Larix occidentalis), Brewer spruce (Picea breweriana), and yellow-cedar (Callitropsis 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].
Botanical Description
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].
An old-growth noble fir's DBH is measured in Oregon, 1945.
Raunkiaer Life Form (Raunkiaer 1934)
- Phanerophyte
Seasonal Development
Noble fir cones, Marys Peak Botanical Special Interest Area, Benton County, Oregon. (CC BY-NC 4.0)
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].
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].
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].
Immediate Fire Effects
Specific information regarding fire-related mortality is lacking. Because of its thin bark, however, it is assumed that young and immature noble fir would likely be killed by moderate to severe fire.
Postfire Regeneration Strategy (Stickney 1989)
- Tree without adventitious-bud root crown
- Secondary colonizer - off-site seed
- Initial-offsite colonizer (off-site, initial community)
Fire Adaptations
The bark of young noble fir is relatively thin [35]. Fire resistance of larger, thicker barked trees is reported to be low [6,35] to moderate [6,25,49]. The foliage of noble fir is moderately to highly flammable [35].
Noble fir prunes well in closed, dense stands [1,18]. Stands dominated by noble fir have the smallest quantities of forest floor material (compared with stands dominated by other western conifers that occur in its range), and accumulation of fuel is low [9,47].
After stand-destroying fires, noble fir and Douglas-fir are initial colonizers [43].
Plant Response to Fire
After a clearcut, seedling density was greater on unburned or low-intensity burned areas compared to areas that burned at moderate to severe intensity [27].
Fire Regimes
For fire regime information, search FEIS for this species by entering the species name on the Advanced Search page and selecting “Fire Regime” as the publication type.
Fire Management Considerations
No entry.
Federal Status
No special status.
Other Status
No entry.
Importance to Wildlife and Livestock
Noble fir provides cover and thermal protection for wildlife [18].
Palatability and Nutritional Value
No entry.
Cover Value
No entry.
Value for Rehabilitation or Restoration of Disturbed Sites
On sizeable clearcuts or burned areas, noble fir can quickly establish; however, actual data varies with site [1,18].
Other Uses
Noble fir brings a substantial price as a Christmas tree [1,16,22]. It is also utilized as ornamental greenery [16,18].
Noble fir is also important in watershed protection [18,22].
The soft wood of noble fir is lightweight and has good form [1,16,18,22]. It is the strongest wood of the true firs [14,17]. The wood is suitable for light construction and pulping [16]. High-quality noble fir wood is used for moldings, sash and door stock, venetian blinds, and veneer [42]. The wood of noble fir is also a specialty wood used for ladder rails and airplane construction because of its high strength to weight ratio [1,16,17,18]. Noble fir wood is exported to Japan for home building [16].
Other Management Considerations
Noble fir is a preferred species for planting or seeding within its range [37]. Based on 10-year performance, noble fir is acceptable for reforestation of high-elevation stock in British Columbia with variable results in productivity [40]. In the Pacific silver fir zone, noble fir maintains good growth in dense stands and is appropriate where summer frost is likely to occur but should not be planted in severe frost pockets of clearcuts [26]. Noble fir is not recommended for planting on sites with a slope of less than 15 degrees [4,26].
Noble fir roots deeply making it resistant to wind damage [1,6]. It has a high frost tolerance and low drought tolerance [12,17].
Generally, noble fir does not suffer major losses from pests [13,16,17]. Noble fir bark beetle (Pseudohylesinus nobilis) is often associated with root-diseased trees and can kill the tree [12,16]. Dwarf mistletoe may be a problem requiring management action in some areas [11,12,16,17,41].
Table A1— Forest and range ecosystems, Bureau of Land Management (BLM) physiographic regions, Kuchler plant associations, Society for American Foresters (SAF) forest cover types, and Society for Rangeland Management (SRM) rangeland cover types in which this species occurs.
Forest and Range Ecosystems (Garrison et al. 1977)
- FRES20 Douglas-fir
- FRES23 Fir - spruce
- FRES24 Hemlock - Sitka spruce
BLM Physiographic Regions (Bernard and Brown 1977)
- 1 Northern Pacific Border
- 2 Cascade Mountains
Kuchler Plant Associations (Kuchler 1964)
- K001 Spruce - cedar - hemlock forest
- K002 Cedar - hemlock - Douglas-fir forest
- K003 Silver fir - Douglas-fir forest
- K004 Fir - hemlock forest
SAF Cover Types (Eyre 1980)
- 205 Mountain hemlock
- 206 Engelmann spruce - subalpine fir
- 224 Western hemlock
- 226 Coastal true fir - hemlock
- 227 Western redcedar - western hemlock
- 229 Pacific Douglas-fir
- 230 Douglas-fir - western hemlock
SRM Rangeland Cover Types (Shiflet 1994)
- No entry
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