Species Review

Abies lasiocarpa, subalpine fir

Written

February, 1991

Contributors

Ronald Uchytil - 1st Author

Uchytil, Ronald J. 1991. Abies lasiocarpa, subalpine 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/abilas

Abbreviation	Common Name	Scientific Name	Classification	Status
Plants
ABILAS	subalpine fir	Abies lasiocarpa	Life Form: Plants/Tree Kingdom: Plantae Class: Conifer Order: Pinales Family: Pinaceae Genus: Abies	Fed. Protected: No Nativity: Native Invasiveness: Noninvasive
ABILASA	corkbark fir	Abies lasiocarpa var. arizonica	Life Form: Plants/Tree Family: Pinaceae Genus: Abies	Fed. Protected: No Nativity: Native Invasiveness: Noninvasive
ABILASL	subalpine fir	Abies lasiocarpa var. lasiocarpa	Life Form: Plants/Tree Family: Pinaceae Genus: Abies	Fed. Protected: No Nativity: Native Invasiveness: Noninvasive

Taxonomy

The genus Abies consists of about 40 species of evergreen trees found in the northern hemisphere. Nine species of Abies, including subalpine fir, are native to the United States [75]. The currently accepted scientific name of subalpine fir is Abies lasiocarpa (Hook.) Nutt. [75]. Subalpine fir is widely distributed and exhibits geographic variation. Two varieties are recognized based on morphological differences [75]:

Abies lasiocarpa var. arizonica, corkbark fir
Abies lasiocarpa var. lasiocarpa, typical variety of subalpine fir

Subalpine fir hybridizes with balsam fir (A. balsamea) where their ranges overlap in the Canadian Rockies [41].

Synonyms

Abies balsamea ssp. lasiocarpa (Hook.) Boivin
Abies balsamea var. fallax (Engelm.) Boivin

Other Common Names

alpine fir, western balsam fir, balsam, white balsam, balsam fir, white fir, Rocky Mountain fir, pino real blanco, cork-bark fir, corkbark fir, Arizona fir

General Distribution

Subalpine fir is the mostly widely distributed fir in North America, spanning more than 32 degrees of latitude [11]. It occurs chiefly in mountainous areas from the Yukon interior near treeline and along the coast of southeastern Alaska south through western Alberta and British Columbia to southern Colorado and scattered mountain ranges of Arizona and New Mexico [54,75]. In the western portion of its range, subalpine fir does not occur along the western slope of the Coast Range in southern British Columbia or along the Coast Ranges of Washington and Oregon but does occur on Vancouver Island and in the Olympic Mountains of Washington [11]. It occurs on both slopes of the Cascade Mountains as far south as southern Oregon [11]. The two varieties are distributed as follows [11,75]:

l. var. lasiocarpa (typical variety) – almost the same as the species, but not in central and southeastern Arizona.
l. var. arizonica – from central Colorado to southwestern New Mexico, and in southeastern and central Arizona.

A map of the southwestern U.S., with scattered counties in Colorado, Arizona, and New Mexico highlighted in green where subalpine fir occurs.

Photo Credit

Map courtesy of USDA, NRCS. 2018. The PLANTS Database. National Plant Data Team, Greensboro, NC [117] [2018, March 22].

Distribution of corkbark fir (A. l. var. arizonica).

A map of the western U.S. and Canada with states and territories highlighted in green where subalpine fir occurs. All of the western U.S., western Canada, and Alaska are highlighted.

Photo Credit

Map courtesy of USDA, NRCS. 2018. The PLANTS Database. National Plant Data Team, Greensboro, NC [117] [2018, March 22].

Distribution of subalpine fir (A. l. var. lasiocarpa).

Subalpine fir and corkbark fir occur together in scattered mountain ranges in southwestern Colorado, northern, western, and southwestern New Mexico, and in the high mountains of Arizona [11].

States and Provinces

United States: AK AZ CO ID MT NV NM OR UT WA WY
Canada: AB BC YT

Site Characteristics

A black and white photo of a line of conifer trees descending a mountain slope with snow-capped mountains in the background.

Photo Credit

Public domain image by Ansel Adams from the series "Ansel Adams Photographs of National Parks and Monuments", compiled from 1941-1942.

Subalpine fir in Glacier National Park.

Subalpine fir is a middle to upper elevation mountain conifer. It generally occupies sites with a short growing season caused by cold winters, cool summers, frequent summer frosts, and heavy snowpack. It forms extensive forests between warm and dry lower elevation forests of Douglas-fir, white fir (Abies concolor), grand fir, lodgepole pine, or blue spruce (Picea pungens) and higher elevation alpine tundra [23,29,112,125]. At its lower elevational limits, subalpine fir is often restricted to streambottoms, ravines, frosty basins, or north exposures. It increasingly occupies westerly and easterly aspects with increasing elevation and may occupy all aspects at upper timberline [23,91].

Stand condition and associated conifers: Throughout its range, subalpine fir is most commonly associated with Engelmann spruce. These two species frequently occur as codominants forming widespread subalpine forests. In the central and southern Rocky Mountains, Engelmann spruce commonly makes up 70 percent of overstory trees, with subalpine fir dominating the understory [9]. Within spruce-fir forests of this region, Engelmann spruce tends to be more important at higher elevations and on wetter sites, while subalpine fir is more abundant on drier lower elevation sites [9]. In the northern Rocky Mountains, subalpine fir typically dominates climax stands, but Engelmann spruce becomes increasingly important on moist, cool sites [23,91]. Other associates which vary by latitude and elevation are listed below [39]:

Location	Elevation	Associates
northern Rocky Mountains	Low	western white pine (Pinus monticola), Douglas-fir, western larch (Larix occidentalis), grand fir, western hemlock (Tsuga heterophylla), western redcedar (Thuja plicata)
northern Rocky Mountains	High	lodgepole pine, subalpine larch (Larix lyallii), whitebark pine (Pinus albicaulis), mountain hemlock
central Rocky Mountains	Low	lodgepole pine, Douglas-fir, aspen (Populus tremuloides), blue spruce
central Rocky Mountains	High	whitebark pine, limber pine (Pinus flexilis), bristlecone pine (P. aristata)
Southern Rocky Mountains	Low	white fir, Douglas-fir, blue spruce, aspen
Southern Rocky Mountains	High	corkbark fir
Cascade Mountains	Low	Pacific silver fir, mountain hemlock, lodgepole pine
Cascade Mountains	High	mountain hemlock, whitebark pine

Understory associates: Understory vegetation is extremely variable, changing with elevation, exposure, and soil moisture. Habitat type and plant association guides describe characteristic understory plants for differing sites.

Elevation: Alexander and others [11] described the following elevational ranges for subalpine fir:

Coast Range of southeastern Alaska - subalpine fir is found from sea level to 3,500 feet (0-1,067 m).
Coast Range and interior plateaus of Yukon Territory and British Columbia - subalpine fir is found from 2,000 to 5,000 feet (610-1,524 m).
Olympic and Cascade Mountains of Washington and Oregon - subalpine fir is generally found from 4,000 to 6,000 feet (1,219-1,829 m), but may be found as low as 2,000 feet (610 m) along cold streambottoms and on lava flows, and as high as 8,000 feet (2,438 m) on sheltered slopes.
Rocky Mountains of British Columbia and Alberta south of the Peace River - subalpine fir is found from 3,000 to 7,000 feet (914-2,134 m) but is more abundant above 5,000 feet (1,524 m).
Rocky Mountains of Montana and Idaho and associated ranges of eastern Oregon and Washington - subalpine fir grows from 2,000 to 11,000 feet (610-3,353 m) but is most common at 5,000 to 9,000 feet (1,524-2,743 m).
Rocky Mountains of Wyoming, Utah, and Colorado - subalpine fir occurs from 8,000 to 11,500 feet (2,438-3,506 m) but is most common at 9,000 to 11,000 feet (2,743-3,353 m).
Rocky Mountains of New Mexico and Arizona - subalpine fir occurs from 8,000 to 12,000 feet (2,438-3,658 m) but is usually found on north slopes from 9,500 to 11,000 feet (2,896-3,353 m).

Plant Communities

Forests in which subalpine fir attains climax dominance or codominance are widespread throughout the mountains of western North America. The subalpine fir series generally occupies cold, high elevation mountain forests. Engelmann spruce (Picea engelmannii) is usually associated with subalpine fir. It occurs as either a climax codominant or as a persistent, long-lived seral species in most subalpine fir habitat types.

Published classification schemes listing subalpine fir as a dominant part of the vegetation in habitat types (hts), community types (cts), plant associations (pas), ecosystem associations (eas), site types (sts) or dominance types (dts) are presented below:

Location	Classification	Authority
Alaska	general veg. cts	Viereck & Dyrness 1980
Arizona: San Francisco Peaks RNA	forest, alpine & meadow cts	Rominger & Paulik 1983
Arizona, New Mexico	forest & woodland cts	Layser & Schubert 1979
Arizona, New Mexico: Apache, Gila, Cibola NFs	forest hts	Fitzhugh & others 1987
Arizona, New Mexico: south of Mogollon Rim	forest hts	Develice & Ludwig 1983b
northern Arizona, northern New Mexico	forest hts	Larson & Moir 1987
Colorado: Arapaho & Roosevelt NFs	forest hts	Hess & Alexander 1986
Colorado: Gunnison & Uncompahgre NFs	forest hts	Komarkova & others 1988
Colorado: Routt NF	forest hts	Hoffman & Alexander 1980
Colorado: White River-Arapaho NF	grassland, shrubland, & forestland hts	Hess & Wasser 1982
Colorado: White River NF	forest hts	Hoffman & Alexander 1983
western Colorado	riparian pas	Baker 1989a
Idaho: Sawtooth, White Cloud, Boulder, & Pioneer Mtns.	general veg. cts	Schlatterer 1972
central Idaho	forest hts	Steele & others 1981
northern Idaho	forest hts	Cooper & others 1987
southeast Idaho	aspen cts	Mueggler & Campbell 1986
eastern Idaho, western Wyoming	forest hts	Steele & others 1983
Montana	forest hts	Pfister & others 1977
Montana	riparian dts	Hansen & others 1988
central, eastern Montana	riparian cts, hts	Hansen & others 1990
northwest Montana	riparian hts, cts	Boggs & others 1990
southwest Montana	riparian rst, cts, hts	Hansen & others 1989
New Mexico: Cibola NF	forest hts	Alexander & others 1987
New Mexico: Lincoln NF	forest hts	Alexander & others 1984
northern New Mexico, southern Colorado	forest hts	Develice & Ludwig 1983a
northern New Mexico, southern Colorado	forest hts	Develice & others 1986
Oregon: Wallowa-Whitman NF	steppe & forest pas	Johnson & Simon 1987
Oregon: Eagle Cap Wilderness	general veg. cts	Cole 1982
Oregon, Washington	general veg. cts	Franklin & Dyrness 1973
Oregon, Washington: Blue Mountains	general veg. pas	Hall 1973
Utah	aspen cts	Mueggler & Campbell 1986
central, southern Utah	forest hts	Youngblood & Mauk 1985
northern Utah	forest hts	Mauk & Henderson 1984
Washington: Okanogan NF	forest pas	Williams & Lillybridge 1983
Washington: Mount Rainier NP	forest pas	Franklin & others 1988
Washington: North Cascades NP	forest pas	Agee & Kertis 1987
eastern Washington, northern Idaho	forest hts, cts	Daubenmire & Daubenmire 1968
Wyoming: Bridger-Teton NF	aspen cts	Youngblood & Mueggler 1981
Wyoming: Medicine NF	forest hts	Alexander & others 1986
Wyoming: Bighorn Mtns.	forest hts	Hoffman & Alexander 1976
Wyoming: Wind River Mtns.	forest hts	Reed 1976
USFS R-2	general veg. pas	Johnston 1987
USFS R-2	general veg. hts, pas	Wasser & Hess 1982
USFS R-4	aspen cts	Mueggler 1988
west-central Alberta	forest hts	Corns 1983
British Columbia	grassland, forest hts	McLean 1970
British Columbia	general veg. eas	Pojar & others 1984
northwest British Columbia	forest eas	Haeussler & others 1985

Botanical Description

Subalpine fir is a native, coniferous, evergreen tree. It is the smallest of the eight species of fir native to the western United States. Five growth forms, each apparently an adaptation to a particular environment, are described below [9,54]:

The typical form is found throughout much of the subalpine zone. These trees have an extremely narrow and dense crown with short branches. Trees growing in openings retain their lower branches, which often droop and extend down to the ground. Trees growing in the overstory may be clear of lower branches for 20 to 30 percent of the tree's height.
A somewhat broad-crowned, bullet-shaped tree is more typical of older specimens and drier climates.
A mature tree with a layered apron is occasionally found in some areas.
A flag form tree often occurs at timberline. These individuals are characterized by an upright trunk that extends above a krummholzlike mat. Branches on the trunk generally grow only along the leeward side of the trunk, giving the plant a flaglike appearance.
The krummholz form is typical of alpine areas above timberline. In these areas, because of cold temperatures and severe winds, subalpine fir grows in dwarfed, shrubby mats along the ground, and is often much broader than it is tall.

The typical form often grows to heights of 60 to 100 feet (18-30 m), and trunk diameters reach 18 to 24 inches (46-61 cm) [39]. Trees up to 130 feet (40 m) tall and 30 inches (76 cm) in diameter have been found but are rare [39]. Subalpine fir grows very slowly; 150- to 200-year-old trees are usually only 10 to 20 inches (25-50 cm) in diameter [39]. Trees seldom live more than 250 years because they are very susceptible to heart rots [9].

Needles are blunt tipped, flattened, and 1 to 1.2 inches (2.5-3 cm) long [25,57]. Bark on young trees is thin, gray, and smooth, with numerous resin vesicles; on older trees it is shallowly fissured and scaly [9]. Corkbark fir is generally recognized by its creamy-white, thick, corky bark [25]. The root system generally is shallow but under favorable conditions may develop relatively deep laterals [9].

Subalpine fir is monoecious. Single or small bunches of erect female cones occur in the upper part of the crown on the upper side of young branches. Dense clusters of the smaller male cones occur lower on the crown on the underside of 1-year-old twigs. Subalpine fir seeds are 0.23 to 0.28 inch (6-7 mm) long and have broad wings about 0.4 inch (1 cm) long [25,121]. Corkbark fir seeds are about 70 percent larger than subalpine fir seeds [39].

Raunkiaer Life Form (Raunkiaer 1934)

Phanerophyte

Seasonal Development

Subalpine fir requires 2 years to complete its reproductive cycle [115]. Cones are initiated in the spring of the first year as microscopic primordia within vegetative buds. Bud differentiation occurs in midsummer, and separate seed-cone and pollen-cone buds develop until each becomes dormant in the fall [115]. During the spring of the second year, cone buds resume growth and conelets are recognizable in the early spring. During the second year, reproduction phenology generally proceeds as follows:

Phenological event	Location	Timing of event	Reference
Flowering	southwest Montana, northwest Wyoming	mid-June - early July	[41,101]
Cones full size	southwest Montana, northwest Wyoming	late August	[41,101]
Seeds dispersed	southwest Montana, northwest Wyoming	early Sept - early Oct	[41,101]
Flowering	northwest Montana, northern Idaho	mid-June - early July	[41,101]
Cones full size	northwest Montana, northern Idaho	late July - early Aug	[41,101]
Seeds dispersed	northwest Montana, northern Idaho	mid-Sept	[41,101]
Flowering	Oregon	late May - early July	[41]
Seed dispersal	Oregon	early Oct	[41]
Male bud burst	Linn County, Oregon	early to mid-May	[45]
Female bud burst	Linn County, Oregon	mid to late May	[45]
Pollen shed	Linn County, Oregon	June	[45]
Seed dispersal begins	Linn County, Oregon	early October	[45]
Flowering	Arizona, San Francisco Peaks	late June	[41]
Cone ripening	Arizona, San Francisco Peaks	mid-Sept - early Oct	[41]
Seed dispersal	Arizona, San Francisco Peaks	late Sept - early Oct	[41]

Regeneration Processes

Cone and seed production

Subalpine fir can begin producing cones when 20 years old and 4 or 5 feet (1.2-1.5 m) tall, but under closed forest conditions seed production is generally not significant until trees are older and taller [11]. Corkbark fir generally does not produce cones until about 50 years old [39]. Nearly all cones are produced on the uppermost part of the crown. Maximum seed production is by dominant trees between 150 and 200 years old [39]. Yearly seed production is very erratic; good seed crops are produced every 3 to 5 years, with light crops or crop failures in between [39,40,54,86]. Corkbark fir is also a poor seed producer, having more crop failure years than good seed crop years [9]. Subalpine fir averages 34,800 seeds per pound (76,700/kg), while corkbark fir seeds average 22,300 per pound (49,150/kg) [41].

Seed predation

Insect pests reduce seed yields by feeding on cones and seeds; however, the magnitude of loss is variable [11]. Red squirrels cut and cache large quantities of subalpine fir cones [9]. After dispersal, numerous small rodents and birds consume seeds from the ground.

Dispersal

Mature subalpine and corkbark fir seeds have a large wing and are dispersed primarily by wind in the fall as cones disintegrate on the tree. Seeds travel primarily in the direction of prevailing winds, but upslope drafts can influence dispersal at low and middle elevations [9]. Studies in Colorado showed that about one-half of subalpine fir seeds dispersed into clearcuts fell within 100 feet (30 m) of the clearcut's windward edge, while the remainder fell within 260 feet (80 m) of the edge [86]. Some seeds are also dispersed by red squirrels which cut and cache cones before they disintegrate; seeds commonly germinate from these middens, forming thickets [71].

Germination and viability

Seeds overwinter under or in snow. This cold, moist stratification is required for germination [41]. Germination begins in the spring a few days after snowmelt and is usually completed within a few weeks [9,106]. Percent germination is low due to unsound seed; about 31 to 38 percent for subalpine fir and 26 to 33 percent for corkbark fir [39,41]. Under natural conditions seeds remain viable for 1 year [41]. Stratification procedures for stored seeds have been described in detail [41,74].

Seedling establishment and survival

Seedlings establish best on mineral soil seedbeds but will also establish on other surfaces including litter, duff, and decaying wood [11]. Because Engelmann spruce requires a mineral soil seedbed, subalpine fir seedlings usually outnumber spruce seedlings in the understory of spruce-fir stands. Thus, even though it is short-lived, many ecologists consider subalpine fir better able to regenerate under climax conditions than Engelmann spruce. Subalpine fir is very shade tolerant and easily establishes under a closed canopy. Throughout the Rocky Mountains subalpine fir is reproducing abundantly under conditions of dense shade and is often abundant as seedlings and saplings in spruce-fir forests, even where Engelmann spruce dominates the overstory [11,67].

At higher elevations, seedling survival is sometimes greater on duff seedbeds because the duff helps protect seedlings from high-intensity summer rain storms and frost heaving [35]. At lower elevations, seedling densities are often greater on mineral soils [35]. In a spruce-fir forest in southeastern Wyoming, Knapp and Smith [67] found that 42 percent of subalpine fir seedlings were on litter deeper than 1 inch (2.5 cm), compared with only 5 percent of Engelmann spruce seedlings. Subalpine fir is able to establish in duff because of its rapid root growth. Comparing seedlings grown in a greenhouse, subalpine fir's taproot length (29 mm) 2 weeks after germination was over 200 percent greater than the taproot length of Engelmann spruce (9.4 mm) [67].

Growth

Subalpine fir seedlings grow very slowly. One-year-old seedlings are frequently less than 1 inch (2.5 cm) tall [11]. One study found 15-year-old seedlings averaged only 11 inches (28 cm) in height on burned-over slopes, 10 inches (25 cm) on cut-over dry slopes, and 6 inches (15 cm) on cut-over wet flats [11]. Under favorable conditions trees reach a height of 4 to 5 feet (1.2-1.5 m) in 20 to 40 years [11]. Under a closed canopy, trees 4 to 6 feet tall (1.2-1.8 m) are often 35 to 50 years old.

Vegetative reproduction

Near timberline subalpine fir frequently reproduces by layering, probably as a result of heavy snow, wind, and cold temperatures which restrict growth away from the ground. Layering often results in clusters of subalpine fir growing near timberline [13]. Under closed forest canopy, reproduction by layering is negligible.

Successional Status

In the Rocky Mountains, subalpine fir is a shade-tolerant climax species favored by long fire-free intervals. Its seedlings outcompete spruces, lodgepole pine, and Douglas-fir when light intensities are less than 50 percent of full sunlight, but cannot compete with these conifers under brighter light [11]. In Montana and Idaho and in the mountains of eastern Washington and eastern Oregon, subalpine fir often forms pure stands at climax, but it may also mix with Engelmann spruce, which, although considered to be seral to subalpine fir, outlives it and persists to climax. In the Rocky Mountains north and south of Montana and Idaho, Engelmann spruce and subalpine fir may codominate at climax [11].

Throughout much of the Cascade Mountains subalpine fir grows as a shade-intolerant, seral species and is gradually replaced by more shade-tolerant associates such as Pacific silver fir, grand fir, and mountain hemlock [43]. It often invades recently disturbed areas with lodgepole pine. It also pioneers harsh sites on raw geologically young surfaces such as lava flows and talus slopes and on climatically harsh sites near timberline [43].

In areas where subalpine fir is a climax dominant, succession following disturbance varies depending upon the severity and type of disturbance, elevation, and the availability of conifer seeds. Subalpine fir may establish immediately following disturbances if mature trees survive to provide seeds and seral species such as lodgepole pine and aspen are scarce. Near treeline, it may take 100 years or more for subalpine fir to establish seedlings following fire because an increase in herbaceous species prevents seeds from reaching mineral soil and the harsh climate kills many seedlings that do establish [18,109]. Aspen and lodgepole pine are the most common seral species. They often form pure stands and completely dominate low and middle elevation stands within the subalpine fir zone following large fires [5,68]. These species grow rapidly and quickly overtop any subalpine fir seedlings that may establish at the same time. Aspen stands can sometimes persist for decades or even centuries when conifer seed trees are eliminated [29]. When lodgepole pine establishes immediately following stand-destroying fires, it often forms even-aged dense stands that dominate for 100 to 300 years. Because it is very shade tolerant, subalpine fir eventually establishes under the pine canopy, usually within 100 years, and attains dominance as the pine stand begins to break up [90,98].

In many of the warmer and lower elevation subalpine fir habitat types, subalpine fir has not achieved climax dominance because of repeated fires which favor shade-intolerant seral conifers. Many of these habitat types are in midsuccessional stages. Lodgepole pine, western larch, western white pine, or Douglas-fir dominate the overstory, but subalpine fir seedlings and saplings occur in the understory [93,113].

Immediate Fire Effects

Subalpine fir is one of the least fire-resistant western conifers. It is very susceptible to fire because it has (1) thin bark that provides little insulation for the cambium, (2) bark which ignites readily, (3) shallow roots which are susceptible to soil heating, (4) low-growing branches, (5) a tendency to grow in dense stands, (6) highly flammable foliage, and (7) moderate to heavy lichen growth [37,111].

Subalpine fir forests are normally subject to highly destructive crown fires that occur at 100-year or longer intervals. Such fires typically kill all subalpine fir trees. Subalpine fir is also very susceptible to surface fires because fine fuels which are often concentrated under mature trees burn slowly and girdle the thin-barked bole [34].

Postfire Regeneration Strategy (Stickney 1989)

crown-stored residual colonizer; short-viability seed in on-site cones
secondary colonizer; off-site seed carried to site after year 2
off-site colonizer; seed carried by wind; postfire years 1 and 2

Fire Adaptations

Plant adaptations to fire: Subalpine fir is very fire sensitive and generally suffers high mortality even from low intensity fires. It relies on wind-dispersed seeds which readily germinate on fire-prepared seedbeds to colonize burned areas. The occasional mature tree which survives fire, those escaping fire in small, unburned pockets, and trees adjacent to burned areas provide seeds to colonize burned sites. In subalpine habitats, scattered subalpine fir trees often escape fire because of discontinuous fuels, broken and rocky terrain, and the moist and cool environment [78,87,91].

Fuels and fire behavior: The fuel structure in subalpine fir-dominated stands promotes highly destructive stand-destroying fires. Fuel loads in subalpine fir stands are greater than in lower elevation montane stands because the cool and moist environment slows the decomposition of organic matter allowing fuels to accumulate more rapidly [1]. Fuel beds tend to be irregular, with over twice as much fuel accumulating under the narrow-crowned trees as between them [116]. The needles are small and fine and form a compact fuel bed in which fire spreads slowly [34]. These concentrated, slow burning fuels frequently produce flames high enough to reach subalpine fir's low-growing dead branches [116]. Thus, crowning is common in subalpine fir stands.

An aerial view of a conifer forest with a large open area where all the trees are down and dead, surrounded by green, living trees.

Photo Credit

Image by Garon Smith, used with permission.

Downed woody fuels resulting from a 2017 avalanche on the Gallatin National Forest.

Once a crown fire begins, it spreads easily because subalpine fir has a tendency to grow in dense stands and has highly flammable foliage. A lightning strike on May 7, 1987, in a subalpine fir-mountain hemlock stand in Mount Rainier National Park started a crown fire even though the ground was still partially snow covered. The fire spread slowly through the tree crowns by (1) igniting lichens draped along the fine branches, (2) preheating and igniting the foliage, and (3) spreading to a nearby tree by igniting its lichens [62].

Plant Response to Fire

Following fire, subalpine fir reestablishes via seeds dispersed by wind from trees surviving in protected pockets or from trees adjacent to burned areas. Subalpine fir readily establishes on burned mineral soil seedbeds [107]. Ash does not affect germination, but if it is deep, it can prevent a seedling's roots from reaching mineral soil [85]. Although seedling establishment is often favored by shade, it will establish in full sunlight following fire [87].

The rate of establishment is quite variable, and depends on the proximity of the seed source (because the heavy seeds are dispersed over short distances) and seed production during the year of the fire and immediate postfire years. In general, subalpine fir seedling establishment is very slow in areas suffering large, continuous crown fires but is relatively rapid on small burned-over areas where a seed source is nearby [90,124,128]. Three years after a late August wildfire in northern Colorado, in a dense, mature stand composed of Engelmann spruce, subalpine fir, and lodgepole pine, subalpine fir had established 15,200 seedlings per acre (37,500/ha) on small burns that were less than one-tenth of an acre in size. But on areas within the middle of the main burn, subalpine fir had established only 12 seedling per acre (30/ha) 3 years after the fire [16]. In Colorado, Peet [90] found a 75-year-old burn that had few conifer seedlings even though an old-growth subalpine fir-Engelmann spruce stand was 218 yards (200 m) away.

Reinvasion into large burns is slow because much of the seed source is destroyed. However, sometimes sporadic survivors provide a limited seed source so that a small number of seedlings establish quickly following fire. When this occurs, large quantities of seeds are dispersed several decades later as the early invading seedlings mature and reach cone bearing age [128].

On areas where subalpine fir is abundant and lodgepole pine scarce before burning, subalpine fir establishes quickly following fire if sufficient numbers of seed trees survive or are near the burn. However, if lodgepole pine is present prior to burning, it usually seeds in aggressively and assumes a dominant role because it quickly overtops any fir seeding in at the same time [34]. Subalpine fir can be suppressed for several decades in seral lodgepole stands which develop following fire; one-hundred-year-old individuals may be only 3 feet (0.9 m) tall [90]. It may take 50 to 150 years after a fire for substantial subalpine fir establishment under dense lodgepole pine stands [18,109,128].

In the Olympic Mountains, tree seedling establishment following fires in closed mountain hemlock-subalpine fir forests was higher during wet growing seasons than during dry growing seasons. Establishment rates were higher near the edge of a fire or near survivors than in areas removed from a seed source [4]. On many burned areas, subalpine fir did not establish seedlings for several years because of poor seed crops. On some burns there was a lag time of 40 to 50 years after fire before there was substantial seedling establishment. This was a result of early invading trees maturing and dispersing seeds [4].

High elevation subalpine fir stands that have burned often remain open for several decades or more [18,31]. The harsh environment near treeline makes it difficult for tree seedlings to establish and survive [18]. Grasses and sedges may form a mat in subalpine meadows which prevents tree seeds from reaching mineral soil [109].

For further information on subalpine fir response to fire, see Fire Case Studies. Hamilton's Research Project Summary and Research Papers (Hamilton 2006a, Hamilton 2006b) provide information on prescribed fire and postfire response of plant community species, including subalpine fir, that was not available when this species review was originally written.

Fire Regimes

Subalpine fir habitat types vary from cold and wet at higher elevations to warm and moist or cool and dry at lower elevations. This environmental gradient influences the mean fire return interval (MFRI). Relatively dry lower elevation subalpine fir habitat types have more frequent and less intense fires than moist middle and upper elevation subalpine fir habitat types [12,91]. Such forests in the Bitterroot National Forest in Montana have a MFRI of 17 to 28 years [14]. Fires at this frequency kill subalpine fir and keep these forests dominated by seral conifers such as lodgepole pine, Douglas-fir, or western larch. Moist, middle and upper elevation subalpine fir habitat types, however, generally experience high intensity stand-replacing fires at intervals of 100 years or more. Mean fire return intervals for middle and upper elevation subalpine fir habitat types in several areas are presented below:

Location	Community dominants	MFRI (years)	Reference
Kananaskis Park, Alberta	subalpine fir, spruce, lodgepole pine	90	[12]
northern Cascades, Washington	subalpine fir	154	[2]
northern Cascades, Washington	subalpine fir-lodgepole pine	109	[2]
Olympic National Park, Washington	subalpine fir	150	[116]
Yellowstone National Park, Wyoming	subalpine fir	300-350	[98]
Coram Experimental Forest, northwest Montana	western larch, Douglas-fir, lodgepole pine, subalpine fir	117-146	[129]

For fire regime information, search FEIS for this species by entering the species name or acronym on the home page and selecting “Fire Regime” as the publication type.

Fire Management Considerations

Subalpine fir is very fire sensitive and is often killed even by surface fires. Following timber harvest, on sites where subalpine fir is not a preferred species, light surface fires may be used to kill subalpine fir and promote the establishment of other conifers [93].

Fuels remain moist in many high elevation subalpine fir habitat types during most of the year, leaving only a short time period during certain years when prescribed burning can take place [63,91].

Subalpine fir seeds germinate poorly in soils under burned slash piles [130] but readily germinate on mineral soil seedbeds prepared by broadcast burning [16,107].

Effects of a prescribed crown fire on Table Mountain, Washington, on subalpine fir

Source

Woodard, Paul Michael. 1977. Effects of prescribed burning on two different-aged high-elevation plant communities in eastern Washington. Seattle, WA: University of Washington. 228 p. Dissertation. [124].

Season/Severity Classification

fall/severe

Study Location

The study took place in the Cascade Mountains in central Washington approximately midway between the towns of Ellensburg and Wenatchee.

Prefire Vegetative Community

The study area is within the subalpine fir (Abies lasiocarpa) zone. Two adjacent but different-aged stands were burned. One area was a young, lodgepole pine (Pinus contorta) thicket, the other was a old, decadent stand of lodgepole pine with subalpine fir and Engelmann spruce (Picea engelmannii) attaining dominance. Each is described below.

Lodgepole pine thicket: Lodgepole pine is the overstory dominant, but subalpine fir and Engelmann spruce are also principal components. Subalpine fir and Engelmann spruce are codominants in the intermediate size classes. Subalpine fir is the only tree regenerating under the canopy. Understory plants include elk sedge (Carex geyeri), Hood sedge (C. hoodii), heartleaf arnica (Arnica cordifolia), broadleaf arnica (A. latifolia), bigleaf lupine (Lupinus polyphyllus), and dwarf bilberry (Vaccinium myrtillus).

Snag area: This is a decadent lodgepole pine stand, with subalpine fir and Engelmann spruce dominating the overstory canopy. Fir and spruce codominate the intermediate size classes, but subalpine fir is the only tree regenerating under the canopy. Predominant understory plants include subalpine fir, elk sedge, broadleaf arnica, and mosses (Rhacomitrium canascens, Polytridum commune).

Site Description

The burned site is a southwest facing gentle slope at an elevation of 5,596 to 5,776 feet (1,706-1,761 m). A total of 27 acres (10.9 ha) were burned.

Climate: The climate is typical of most areas within the subalpine zone. The winters are cold and wet and the summers cool and dry. Frost and freezing temperatures can occur during any month of the year. Over 70 percent of precipitation falls as snow between October and March.

Soil and duff: The two stands have similar soils, but the soil in the snag area is more fertile and better developed. In both areas soils are derived from basalt residium, have a clay-loam texture, and average 6 inches (15.2 cm) deep. The effective rooting depth was about 20 inches (51 cm) in the thicket area, and 20 to 40 inches (51-102 cm) in the snag area. On both areas, duff was generally from 1 to 4 inches (0.4-1.6 cm) thick. The mean depth of duff was 2.3 inches (5.94 cm) on the thicket area, and 1.9 inches (4.92 cm) on the snag area.

Fuel loading: Prior to burning, mean fuel loads were as follows:

Fuels	Size class	Thicket area		Snag area
Fuels	Size class	Tons/acre	Tonnes/ha	Tons/acre	Tonnes/ha
Dead and down wood	0.0-0.25 inch (0.0-0.6 cm)	0.6	1.3	0.9	2.0
	0.26-0.99 inch (0.61-2.5 cm)	2.1	4.6	2.9	6.4
	1.0-3.0 inches (2.6-7.6 cm)	4.4	9.8	5.1	11.4
	> 3.0 inches (7.6 cm) rotten	17.4	38.9	30.9	69.2
	> 3.0 inches (7.6 cm) solid	17.0	38.1	50.1	112.2
Litter		41.4	92.7	89.8	201.2
Duff		32.5	72.8	30.0	67.1

Fire Description: The fire was ignited with drip torches on September 30, 1975, taking approximately 1 hour and 20 minutes to ignite the entire 27 acres (10.9 ha). Actual fire prescriptions at the time of ignition were as follows:

ambient air temperature = 60 to 63 degrees F (16-17 C)
relative humidity = 19-21 percent
wind = calm gusts to 15.6 miles/hr (26 km/hr), from the south-southwest
days since last rain = 15
fine fuel moisture content = 13 percent

Within about 10 minutes after ignition, trees began to crown out. Fire behavior for each area is summarized below:

Snag area: Crowning occurred throughout most of the snag area. Flame heights were estimated to be 125 feet (38 m) by one observer, and 50 feet (15 m) above the tops of 90 foot (27 m) crowns by two other observers. The fire consumed all small downed and dead wood from 0.0 to 1 inch (0-2.5 cm) in diameter, as well as needles and small twigs on live standing trees. Ninety-six percent of down and dead fuels less than 3 inches (7.6 cm) in diameter were consumed. In general, 90 to 100 percent of the duff layer was removed. Many trees less than 3 inches (7.6 cm) in diameter at the base were completely consumed, and nearly all standing snags were blown down or burned down. Where crowning occurred, the only thing that remained immediately following the fire was reddened soil, ash-covered soil, large-diameter logs, and dead trees.

Lodgepole thicket: Fire within the lodgepole thicket was much less severe. The crown fire which occurred within the snag area stopped when it met the boundary of the lodgepole thicket. Dead and down fuels less than 3 inches (7.6 cm) in diameter were reduced by 70 percent. Dead and down fuels greater than 3 inches (7.6 cm) in diameter were reduced 34 percent. Duff was reduced about 25 percent.

Fire Effects on Target Species

Where crowning occurred subalpine fir suffered 100 percent mortality. Fire burning within the crown of live trees consumed all needles and small twigs leaving scorched skeletons. Many live trees less than 3 inches (7.6 cm) in diameter at the base were completely consumed.

One year after this fire, subalpine fir seedlings established from seed produced by unburned trees adjacent to the burned area. However, stocking was considered low and attributed to a poor seed crop. Seedling establishment was restricted to areas along the margin of the burn.

Subalpine fir pre and postfire frequency and cover are summarized below:

Abundance	Thicket area		Snag area
Abundance	Prefire	Postfire	Prefire	Postfire
Frequency	100%	38%	100%	12%
Relative ground cover	37%	12%	20%	4%

Fire Management Implications

High intensity crown fires which are common in subalpine fir forests, kill all or nearly all seed trees within a burned area. If subalpine fir is to naturally regenerate on this type of burn, seeds must come from adjacent unburned stands. Because subalpine fir seeds are dispersed over relatively short distances, initial seedling establishment is restricted to the burn's edge. Subalpine fir cone production can be erratic from year to year, with the best regeneration occurring during good seed crop years.

Federal Status

None

Other Status

No entry.

Importance to Wildlife and Livestock

Subalpine-fir-dominated stands generally do not produce enough forage for livestock but do provide browse and cover for large and small wildlife species. Mule deer, elk, moose, woodland caribou, black bear, and grizzly bear often use subalpine fir habitats as summer range [10,23,113]]. Subalpine fir forests are generally not suitable winter range for deer and elk because of heavy snowpack, but some lower elevation subalpine fir habitat types are used by moose and woodland caribou during the winter [23,61,89]. Subalpine fir forests support numerous species of small mammals and birds. The snowshoe hare, flying squirrel, red squirrel, porcupine, pine marten, fisher, lynx, and several species of mice, voles, chipmunks, and shrews all inhabit subalpine fir forests [26,104,113]. Numerous species of birds nest and feed in subalpine fir forests, including several woodpeckers, flycatchers, kinglets, nuthatches, juncos, thrushes, chickadees, crossbills, the pine siskin, owls, and grouse [104,113].

The young growth of subalpine fir is sometimes eaten by mule deer, elk, bighorn sheep, and snowshoe hares, but it is not an important food item. Subalpine fir comprises only a small portion of the summer diet of mountain goats but can be a major food source in the winter and spring [99]. Throughout much of Montana, Idaho, and Wyoming, subalpine fir is an important winter food of moose [89]. On moose winter range near Jackson Hole, Wyoming, an average of 13 to 18 percent of small subalpine fir trees were browsed by moose, and 44 to 78 percent of the branches on trees browsed were utilized [61]. In Yellowstone National Park, grizzly bears sometimes strip the bark of subalpine fir to feed on the underlying cambium [19]. The winter diet of blue grouse consists primarily of conifer needles. These grouse often winter in subalpine stands and may feed heavily on the needles and buds of subalpine fir [103,113].

Subalpine fir seeds are eaten by several species of small mammals and birds. Red squirrels eat seeds from cached subalpine fir cones [71]. Fir seeds are also eaten by chipmunks and mice. Several birds, including chickadees, nuthatches, crossbills, the pine siskin, and the Clark's nutcracker remove and eat the seeds from fir cones [49,77]. Because subalpine fir seeds are large, comprising about 26 percent of a cone's weight, they are an energy-efficient food source for small birds [49]. Small birds may make considerable use of fir seeds, but their foraging is scattered and sporadic throughout subalpine forests [49].

Palatability and Nutritional Value

The palatability of subalpine fir to domestic livestock is low [30]. Its palatability to big game animals is generally low also, but in some locations it is highly palatable to moose and mountain goats during winter and spring [89,99]. The seeds are palatable to numerous small mammal species [77]. Red squirrels generally eat subalpine fir seeds after other cached conifer seeds have been consumed [71]. The needles are highly palatable to blue grouse.

The relish and degree of use shown by livestock and wildlife species for subalpine fir in several western states is rated as follows [30,61,89,96]:

Species	Colorado	Montana	Wyoming	Utah	Idaho
Cattle	Poor	Poor	Poor	Poor	—
Sheep	Poor	Poor	Poor	Poor	—
Horses	Poor	Poor	Poor	Poor	—
Pronghorn	—	—	Poor	Poor	—
Elk	—	Poor	Poor	Poor	—
Moose	—	Good	Good	—	Fair
Mule deer	—	Poor	Poor	Poor	—
White-tailed deer	—	—	Poor	—	—
Small mammals	—	Fair	Fair	Good	—
Small nongame birds	—	—	Fair	Good	—
Upland game birds	—	Fair	Fair	Good	—
Waterfowl	—	—	Poor	Poor	—

Subalpine fir is low in protein value but fair in energy value [30]. Percent composition of subalpine fir browse collected near Jackson Hole, Wyoming, was as follows [61]:

Date collected	Crude protein	Ether extract	Crude fiber	Nitrogen free extract
11/25	5.57	7.53	20.19	50.26

A study in Montana found the following mean concentration of elements in subalpine fir needles and twigs [110]:

Element	1-yr-old green needles	Twigs <0.25 inch (0.64 cm) in diameter
Ca (micrograms/gram)	9,722	5,840
Cu (micrograms/gram)	7.4	7.9
Fe (micrograms/gram)	64	182
K (micrograms/gram)	5,553	7,031
Mg (micrograms/gram)	819	1,038
Mn (micrograms/gram)	1,020	587
N (micrograms/gram)	10,690	4,962
Na (micrograms/gram)	103	124
P (micrograms/gram)	1,450	2,254
Zn (micrograms/gram)	43	5
Ash (percent)	3.5	3.5

Cover Value

Big game: Subalpine fir habitat types provide excellent hiding cover for deer, elk, mountain goats, moose, and bear [10,113]. Certain low elevation subalpine fir forests may be used by elk during calving, and high elevation subalpine fir forests by bighorn sheep during lambing and lamb rearing [113]. Dense stands provide cool summertime shade for big game animals [71]. In Yellowstone National Park, grizzly bear daybeds are often found in subalpine fir stands [19].

Small mammals and birds: Small subalpine firs provide good year-round hiding cover. Dense thickets of small trees are often nearly impenetrable and provide hiding places for small mammals such as snowshoe hares and porcupines [13,71]. Blue grouse often overwinter in subalpine trees and rely almost exclusively on them for escape cover [103]. Subalpine fir snags are used by numerous cavity-nesting birds, but are generally less preferred than those of associated conifers [105].

The degree to which subalpine fir provides environmental protection during one or more seasons for wildlife species is as follows [30]:

Species	Colorado	Montana	Wyoming	Utah
Pronghorn	—	—	Poor	Poor
Elk	Good	Fair	Good	Good
Mule deer	Good	Fair	Good	Good
White-tailed deer	—	—	Poor	—
Small mammals	Good	Good	Good	Good
Small nongame birds	Good	Fair	Good	Good
Upland game birds	Good	Good	Good	Fair
Waterfowl	—	—	Poor	Poor

Value for Rehabilitation or Restoration of Disturbed Sites

Subalpine fir can be planted on disturbed sites within forest vegetation types where it naturally occurs [92]. It is generally recommended for cool and moist sites within subalpine areas [120]. Its erosion control potential is listed as medium in Utah and Montana, and high in Colorado [30]. Because this wide-ranging tree exhibits a large degree of genetic variation, seed or nursery stock for rehabilitation projects should come from a local source. Transplanting nursery stock is generally more successful than direct seeding [92]. Seedlings exhibit very slow initial growth and are therefore usually outplanted as 2- to 3-year-old seedlings [41]. Wild seedlings may also be transplanted [120]. A maximum spacing of 10 x 10 feet (3 x 3 m) has been recommended for seedlings or transplants [120]. Methods for collecting, processing, testing, storing, and planting subalpine fir seeds have been discussed in detail [32,41].

Other Uses

Subalpine fir is sometimes used as a landscape plant to produce screenings or windbreaks [114]. In the Pacific Northwest it is sometimes transplanted into rock gardens or simulated subalpine settings [69].

Native Americans used various parts of subalpine fir for numerous purposes. A hair tonic was prepared by mixing powdered needles with deer grease. Finely ground needles were also sprinkled on open cuts. Sticky resin collected from the bark was boiled and used as an antiseptic for wounds or as a tea for colds. Boughs were placed in rooms for their aroma, and pulverized needles were used as a body scent or as perfume for clothing [53].

Resin from the bark is used in the optical industry and in laboratories as a cement for lenses and microscope slides [71].

Wood Products Value: Subalpine fir wood is odorless, light-weight, soft, and low in bending and compressive strength [11]. It is easy to work, glues well, and holds nails and screws fairly well. The wood is primarily used for products such as lumber for home construction and for prefabricated wood products [9]. Subalpine fir has excellent pulping properties [9]. Use for poles and pilings requires large amounts of preservatives because the wood decays rapidly [108].

Other Management Considerations

Timber harvest: Shelterwood and individual tree selection silvicultural methods favor subalpine fir over Engelmann spruce, lodgepole pine (Pinus contorta), and Douglas-fir (Pseudotsuga menziesii); clearcutting and group selection cutting favor subalpine fir over Pacific silver fir (Abies amabilis), grand fir (A. grandis), and mountain hemlock (Tsuga mertensiana) where they grow together [11]. The seed tree method is generally not used because of the susceptibility of subalpine fir to windthrow [11]. In the Rocky Mountains, clearcutting and shelterwood cutting have been the most commonly used harvesting methods in old-growth Engelmann spruce-subalpine fir stands because these stands tend to be even-aged and overmature [8]. Uneven-aged silviculture can pose a problem because residual subalpine fir trees damaged during thinning operations are susceptible to attack by decay fungi. Silvicultural systems and cutting methods for managing subalpine fir have been discussed in detail [7,8,9,11].

Pests and diseases: Subalpine fir is attacked by numerous insects. The most destructive seem to be the western spruce budworm, western balsam bark beetle, and balsam woolly aphid [11]. Subalpine fir is one of the most common hosts of the western spruce budworm. This pest generally attacks low and middle elevation subalpine fir forests but is largely absent from high elevation forests [21]. The balsam woolly aphid has virtually eliminated subalpine fir from some stands in the Cascades [11]. Other insect pests include the Douglas-fir tussock moth, western black-headed budworm, and fir engraver beetle.

Subalpine fir is susceptible to annosus root disease, caused by the fungus Heterobasidion annosum, which results in root and butt decay. Outbreaks of this disease are often centered around large 20-year-old or older fir stumps that contain the fungus' fruiting bodies [102]. Subalpine fir is most seriously affected by this disease in the northern and central Rocky Mountains [123], and is affected to a lesser extent in the Pacific Northwest [102]. Subalpine fir is susceptible to several other wood rotting fungi that cause heart, trunk, butt, or root rots, including brown stringy rot, red heart rot, red ring rot, shoestring rot, brown cubical rot, white spongy root rot, and white pocket rot [39]. Trees weakened by wood rots often become infested by fir engraver beetles and usually succumb to windfall and breakage [11]. Fir broom rust is another common problem in Engelmann spruce-subalpine fir stands and causes bole deformation, spike tops and wind breakage, and makes trees more susceptible to decay fungi [11].

Habitat for threatened and endangered species: Old-growth subalpine fir stands in northern Idaho may provide critical habitat for woodland caribou [23]. Numerous subalpine fir habitat types, especially those containing huckleberries (Vaccinium spp.), provide critical habitat for grizzly bears [127].

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
FRES22 Western white pine
FRES23 Fir - spruce
FRES24 Hemlock - Sitka spruce
FRES25 Larch
FRES26 Lodgepole pine
FRES44 Alpine

BLM Physiographic Regions (Bernard and Brown 1977)

1 Northern Pacific Border
2 Cascade Mountains
5 Columbia Plateau
6 Upper Basin and Range
8 Northern Rocky Mountains
9 Middle Rocky Mountains
11 Southern Rocky Mountains
12 Colorado Plateau

Kuchler Plant Associations (Kuchler 1964)

K004 Fir - hemlock forest
K012 Douglas-fir forest
K015 Western spruce - pine forest
K018 Pine - Douglas-fir forest
K020 Spruce - fir - Douglas-fir forest
K021 Southwestern spruce - fir forest
K052 Alpine meadows and barren

SAF Cover Types (Eyre 1980)

201 White spruce
202 White spruce - paper birch
205 Mountain hemlock
206 Engelmann spruce - subalpine fir
208 Whitebark pine
209 Bristlecone pine
210 Interior Douglas-fir
212 Western larch
213 Grand fir
215 Western white pine
216 Blue spruce
217 Aspen
218 Lodgepole pine
219 Limber pine
223 Sitka spruce
224 Western hemlock
226 Coastal true fir - hemlock
253 Black spruce - white spruce

SRM Rangeland Cover Types (Shiflet 1994)

No entry.

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Last updated June 9, 2025

Abies lasiocarpa, subalpine fir

Abies lasiocarpa, subalpine fir

Citation

Species in This Review

Image Gallery

Introduction

Taxonomy

Synonyms

Other Common Names

Distribution

General Distribution

States and Provinces

Site Characteristics

Plant Communities

Botanical and Ecological Characteristics

Botanical Description

Raunkiaer Life Form (Raunkiaer 1934)

Seasonal Development

Regeneration Processes

Cone and seed production

Seed predation

Dispersal

Germination and viability

Seedling establishment and survival

Growth

Vegetative reproduction

Successional Status

Fire Ecology and Management

Immediate Fire Effects

Postfire Regeneration Strategy (Stickney 1989)

Fire Adaptations

Plant Response to Fire

Fire Regimes

Fire Management Considerations

Fire Case Studies

Effects of a prescribed crown fire on Table Mountain, Washington, on subalpine fir

Source

Season/Severity Classification

Study Location

Prefire Vegetative Community

Site Description

Fire Effects on Target Species

Fire Management Implications

Nonfire Management Considerations

Federal Status

Other Status

Importance to Wildlife and Livestock

Palatability and Nutritional Value

Cover Value

Value for Rehabilitation or Restoration of Disturbed Sites

Other Uses

Other Management Considerations

Appendix

References