Subalpine fir (Bl) - Abies lasiocarpa
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External Links Other external information on Subalpine fir
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BC Distribution of Subalpine fir (Bl)
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Old-growth, subalpine fir stands cover a large area of the ESSF zone, particularly in wetter areas, such as northwest of Smithers
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| Description |
Subalpine fir is a medium - to large-sized (exceptionally >40 m tall), evergreen conifer, at maturity with a low-taper stem, narrow, dense, cylindrical crown, with a spire-like top, short, drooping branches, and grayish-brown bark, breaking into irregular scales with age. Its light, soft, odorless wood is used mainly for lumber.
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Geographic Range
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Geographic element: Western North American/mainly Cordilleran and less Pacific Distribution in Western North America: (central) in the Pacific region; north, central, and south in the Cordilleran region Ecological Amplitudes Climatic amplitude: (alpine tundra) - continental subalpine boreal - montane boreal - (cool temperate) Orographic amplitude: montane - subalpine - (alpine) Occurrence in biogeoclimatic zones: (lower AT), submaritime MH, SWB, ESSF, MS, (BWBS), SBS, (upper IDF), upper ICH, (wetter submaritime CWH) Subalpine fir grows mainly in humid, continental boreal climates, with a short growing season; less frequently in cool temperate climates, with a longer growing season. When these climates become drier and/or warmer, subalpine fir is absent or its occurrence is rare (e.g., in the SBPS and PP zones). Edaphic Amplitude Range of soil moisture regimes: (moderately dry) - slightly dry - fresh - moist - very moist - wet Range of soil nutrient regimes: very poor - poor - medium - rich - very rich Field studies indicate that subalpine fir is most vigorous on moist and rich sites, with calcium - and magnesium-rich soils such as those derived from basaltic or limestone parent materials. On very moist sites, such edaphic conditions are usually a result of seepage. The native range of subalpine fir in British Columbia. |
Ecological Amplitudes
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Geographic element: Western North American/mainly Cordilleran and less Pacific Distribution in Western North America: (central) in the Pacific region; north, central, and south in the Cordilleran region Ecological Amplitudes Climatic amplitude: (alpine tundra) - continental subalpine boreal - montane boreal - (cool temperate) Orographic amplitude: montane - subalpine - (alpine) Occurrence in biogeoclimatic zones: (lower AT), submaritime MH, SWB, ESSF, MS, (BWBS), SBS, (upper IDF), upper ICH, (wetter submaritime CWH) Subalpine fir grows mainly in humid, continental boreal climates, with a short growing season; less frequently in cool temperate climates, with a longer growing season. When these climates become drier and/or warmer, subalpine fir is absent or its occurrence is rare (e.g., in the SBPS and PP zones). Edaphic Amplitude Range of soil moisture regimes: (moderately dry) - slightly dry - fresh - moist - very moist - wet Range of soil nutrient regimes: very poor - poor - medium - rich - very rich Field studies indicate that subalpine fir is most vigorous on moist and rich sites, with calcium - and magnesium-rich soils such as those derived from basaltic or limestone parent materials. On very moist sites, such edaphic conditions are usually a result of seepage. The native range of subalpine fir in British Columbia. |
| Root System Characteristics | In moderately deep, freely drained soils, subalpine fir develops a relatively deep root system; a relatively flat, plate-like root system is formed in poorly drained soils. A superficial lateral root system develops in suppressed seedlings, saplings, and even poles. Fine roots occupy predominantly surface organic layers and are associated with ecto - and endo-mycorrhizae. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Tolerances |
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| Damaging Agents |
Additional information for Bl damaging agents
From the Pacific Forestry Centre:
Diseases for Subalpine Fir from Pacific Forestry Centre Pests
Western Spruce Budworm
Balsam Wooly Adelgid
Root Rots Indian Paint Fungi
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| Associated tree species and successional role | In British Columbia, subalpine fir grows in pure stands or in a variety of mixed-species stands, with one or more tree species. It is often a pioneer species (primary succession) and present in early, intermediate, and late stages of secondary succession; a minor component in old-growth stands in the MH, SWB, IDF, ICH, and CWH zones, and a major component in old-growth stands in the ESSF, MS, BWBS, and SBS zones. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||
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| Silvical Characteristics |
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Genetics and Notes
| Genetics | Information on subalpine fir population differences is virtually nonexistent. Undoubtedly, any species with the range in elevation and latitude of subalpine fir will exhibit differences in growth, phenology, dormancy, resistance to heat and cold, etc., among different populations. Corkbark fir is the only recognized natural variety of subalpine fir. Some evidence from field studies on young trees suggests that subalpine fir may hybridize with grand fir or Pacific silver fir, however, such hybrids have not been described (aforementioned observations were made in the Fraser, Skagit, and Skaist River valleys). |
| Notes |
Subalpine fir is a very productive species on a wide range of sites. Its productivity results from large leaf biomass, high, shade tolerance, low crown spatial requirements (high basal area), low taper, and thin bark. These characteristics pertain to the whole genus Abies. The high shade tolerance of subalpine fir makes the species a desirable component in mixed-species stands, mainly with Engelmann and interior (hybrid) spruce. Subalpine fir as well as spruce is well suited for very moist and poorly aerated sites. Natural regeneration occurs on a variety of seedbeds and advance regeneration responds well to release; thus, natural regeneration should be preferred to planting, especially on subalpine sites, considering a slow initial growth. Subalpine fir, when in stands developed from advanced regeneration, is very susceptible to attack by Indian paint fungus, which destroys the heartwood. Thus, pure subalpine fir stands may be a poor silvicultural option. Engelmann spruce or interior spruce, which show higher resistance to Indian paint fungus, may ensure good timber production, when planted immediately after cutting. More detailed silvics information is given by: Alexander, R.R., R.C. Shearer, and W.D. Shepperd. 1990. Abies lasiocarpa. Pp. 60-70 in R.M. Burns and B.H. Honkala (technical coordinators) Silvics of North America, Vol. 1. Agri. Handbook 654, USDA For. Serv., Washington, D.C. Oliver, C.D. and R.M. Kenady. (editors) 1983. Proceedings of the biology and management of true firs in the Pacific Northwest. Symposium Contribution No. 45, College of Forest Resources, University of Washington, Seattle Washington. |