Index of Species Information

SPECIES:  Larix lyallii


SPECIES: Larix lyallii
AUTHORSHIP AND CITATION : Habeck, R. J. 1991. Larix lyallii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: [].
ABBREVIATION : LARLYA SYNONYMS : NO-ENTRY SCS PLANT CODE : LALY COMMON NAMES : alpine larch subalpine larch lyall larch lyall's larch tamarack woolly larch timberline larch TAXONOMY : The currently accepted scientific name of alpine larch is Larix lyallii Parl [20]. There are no recognized subspecies, varieties, or forms of alpine larch. Hybridization with western larch (Larix occidentalis) results in a genetically different tree [2,6,7]. Although these hybrids occupy a similar geographic area, they inhabit different altitudinal zones, separated from each other by 500 to 1,000 feet (150-300 m) [2]. Differentiation between alpine larch and hybrids can be determined by analyzing the foliar terpenes and volatiles [7,15]. LIFE FORM : Tree FEDERAL LEGAL STATUS : No special status OTHER STATUS : NO-ENTRY


SPECIES: Larix lyallii
GENERAL DISTRIBUTION : Alpine larch occupies two mountain systems: the northern Rockies and northern Cascades [3,16]. It can be found on high mountains in southern British Columbia and Alberta, north-central Washington, north-central and east-central Idaho, and western Montana [1,13,23]. Alpine larch exhibits a highly discontinuous distribution, which is believed to be a remnant of a continuous range existing at a time when cooler, more extensive timberline habitat existed [1,3]. Typical alpine larch stands are often isolated pockets of open, parklike groves, less than 0.05 acre (0.2 ha) [3]. ECOSYSTEMS : FRES23 Fir - spruce FRES25 Larch STATES : ID MT WA AB BC BLM PHYSIOGRAPHIC REGIONS : 2 Cascade Mountains 8 Northern Rocky Mountains KUCHLER PLANT ASSOCIATIONS : K004 Fir - hemlock forest K015 Western spruce - fir forest SAF COVER TYPES : 205 Mountain hemlock 206 Engelmann spruce - subalpine fir 208 Whitebark pine 212 Western larch SRM (RANGELAND) COVER TYPES : NO-ENTRY HABITAT TYPES AND PLANT COMMUNITIES : Alpine larch is a dominant species occupying the timberline habitat type within the subalpine fir (Abies lasiocarpa) series [23]. Principal associates include whitebark pine (Pinus albicaulis), subalpine fir, and Engelmann spruce (Picea engelmannii) [3]. Major undergrowth species include mountain-heather (Phyllodoce empetriformis), smooth woodrush (Luzula hitchcockii), and grouse whortleberry (Vaccinium scoparium) [3,9,23]. See successional status for more information. Publications listing alpine larch as an indicator or dominant species in habitat types (hts), community types (cts), or vegetation types (vts) are listed below: Area Classification Authority MT forest hts Pfister & others 1977 n ID general veg. cts Cooper & others 1991 s AB general veg. vts Holland & others 1982


SPECIES: Larix lyallii
WOOD PRODUCTS VALUE : Alpine larch wood has no potential commercial value [2,7]. No site index or yield data have been developed for alpine larch stands. Annual yield capability has been estimated to be only 10 to 20 cubic feet per acre (0.7-1.4 m3/ha) on sites having better than average productivity [23]. Defect is very high, and no commercial timber harvesting has been reported, or is likely [2]. IMPORTANCE TO LIVESTOCK AND WILDLIFE : Many timberline bird and mammal species are associated with alpine larch communities. Mountain goat, bighorn sheep, hoary marmot, pika, mule deer, elk, black and grizzly bear, red squirrel, and snowshoe hare are among the mammals that feed in alpine larch stands. Blue grouse feed heavily on the needles. Two studies suggest that alpine larch foliage may be one of the most important summer foods for blue grouse [3]. PALATABILITY : Big mammals do not heavily browse alpine larch branches, twigs, or foliage. The primary consumers of needles are upland game birds such as the blue grouse. NUTRITIONAL VALUE : NO-ENTRY COVER VALUE : Alpine larch provides concealment and thermal cover in an otherwise open habitat. Woodpeckers and other cavity nesters utilize the hollowed-out portions of larger trees. Larger mammals may utilize alpine larch stands as windbreaks or burrows [3]. Grizzly bears often den in alpine larch stands in Banff National Park [2]. VALUE FOR REHABILITATION OF DISTURBED SITES : Alpine larch contributes to watershed protection by stabilizing snow loads on steep northern slopes, and thus reducing the threat of avalanches. Alpine larch is considered useful for high-elevation reclamation projects [2]. OTHER USES AND VALUES : Alpine larch communities are valued as wildlife habitat, and for outdoor recreation and esthetics [2]. Photographers and hikers appreciate the changing colors of alpine larch, which is a translucent bright green in summer, and lemon yellow and gold in fall. Dendrochronologists have found alpine larch to be an excellent indicator of climatic variability [8]. OTHER MANAGEMENT CONSIDERATIONS : Alpine larch is generally not placed under active management. Disease or insects cause little damage to this tree. Occasionally, damage may occur by an unidentified fly larvae (Diptera), which destroyed a heavy seed crop in north-central Washington [3]. It is suspected that the larch case bearer (Coleophora laricella) will eventually spread from lower western larch stands to alpine larch stands [3]. Brown heart rot caused by Quinine fungus (Fomes officinales) is often found in alpine larch, but not often enough to be considered prevalent. Needle blight (Sarcotrochila alpina) and cast fungi (Hypodermella laricis) severely infected many stands of alpine larch in British Columbia. The most common fungus infecting alpine larch is an unidentified canker, similar to the European larch canker (Dasyscypha willkommii). This fungus creates noticeable swellings in young and mature twigs. These fungi weaken but usually do not kill the tree [3].


SPECIES: Larix lyallii
GENERAL BOTANICAL CHARACTERISTICS : Alpine larch is an intolerant, native, deciduous, coniferous tree [2,13]. Dominant alpine larch usually live 400 to 500 years, but many trees reach 700 years, and the oldest individuals may live up to 1,000 years [1]. Alpine larch generally has one erect bole, with a braided stem. It rarely grows as krummholz because its leaves are deciduous and its buds are woody and protected [2,18]. Young alpine larch have very flexible boles, which allow them to occupy snowslide and snow creep sites [3]. As a high-elevation species, it averages 40 to 50 feet (12-15 m) in height and 12 to 24 inches (30-60 cm) in d.b.h. on north-facing slopes. The largest recorded alpine larch, found in the Cascade range of Washington, is 95 feet (29 m) tall and 79 inches (201 cm) d.b.h. Alpine larch produces a coating of white tomentum on its growing shoots. This 'wool' remains present for at least 1 year and is believed to decrease water loss from these shoots by increasing the boundary layer [25]. The leaves are grouped into clusters of 30 to 40 rigid needles, borne on short, light bluish-green spurs, 1 to 2 inches (2-4 cm) long. The bark is thin (generally less than 1 inch), initially smooth, becoming more deeply furrowed with age. Cones are reddish-yellow to purple-green and 1 to 2 inches (3-5 cm) long. The bracts are much longer than the cone scales [22]. Alpine larch trees are generally deeply rooted on poor soils. They are well anchored by a large taproot and long, continuous lateral roots [3]. RAUNKIAER LIFE FORM : Phanerophyte REGENERATION PROCESSES : Flowering and fruiting: Alpine larch can begin producing cones when they are 100 years old, but generally do not produce seed in quantity until they reach 200 years of age [3]. Alpine larch are monoecious. Pollen is wind-dispersed from the male strobili in June, and by September, small purplish cones 1.5 to 2.0 inches (4-5 cm) long emerge. Low cone production can be attributed to late season frost damage. Other factors limiting fertilization, pollination, and seed maturation are unknown [2]. Seed production and dissemination: Large seed crops are infrequent, occurring only 1 year out of 10 in Montana. Seeds are winged and are usually wind-disseminated in September. Snowslides have been known to transport seeds to lower elevations [7]. Cleaned seed number between 105,000 and 163,000 per pound (231-359 500/kg). Seed destruction by fungi and larvae are discussed under management considerations. Seedling establishment: Studies have shown that without seed scarification, germination rates are poor. Dry winds and high temperatures on southern slopes probably contribute to poor germination [3]. Soaking seeds for 24 hours in 3 percent hydrogen peroxide solution can improve seed germination [3,26]. Alpine larch seedlings generally have five cotyledons, although four or six may appear. They are narrow, pointed, and 0.4 to 0.6 inch (1.0-1.5 cm) long. Germination is epigeal. Successful germination takes place mostly on moist mineral soil surfaces on northern aspects. Richards [25], however, found that height and diameter growth for young alpine larch was 1.5 times greater on southern exposures than on northern. Seeds of alpine larch germinate in July, soon after snowmelt; they require full light and low temperatures for germination [2]. For the first 20 to 25 years, growth is typically very slow. This strategy allows for extensive establishment of the root system and decreases the probably of top-kill from windthrow or heavy snowpack [2]. Alpine larch apparently become deeply rooted; thus, soil moisture near the surface seems to have no influence on their growth [3]. Seedlings 16 to 25 years old and only 8 to 16 inches (20-40 cm) tall had taproots penetrating 16 to 24 inches (20-40 cm) and laterals 8 to 24 inches (20-60 cm) beneath the surface [25]. Alpine larch seedlings and saplings up to 3 or 4 feet (1.00-1.25 m) tall exhibit evergreen basal limbs. This foliage lasts for two summers and helps establish alpine larch on severe sites [3]. Hybridization is known to occur between alpine larch and western larch [17]. Areas most likely to support hybrid populations are those that have experienced natural disturbances, such as snow or rock slides. The creation of such microsites may allow these species to intermingle because of their varying successional adaptabilities [17]. Vegetative reproduction: Alpine larch does not reproduce from sprouts. Layering has been known to occur only in a few severely stunted trees or krummholz [3]. SITE CHARACTERISTICS : Climate: Alpine larch is most commonly found in very cold, moist, high altitude sites. Altitudinal limits are approximately 5,800 to 9,900 feet (1,770-3,010 m) [3,16]. The mean temperatures are below freezing for 6 months [2]. Mean annual precipitation on most alpine larch sites is between 32 and 75 inches (800 and 1,900 mm), occurring principally in the form of snow and sleet. Periods of drought do occur in late summer but have minor effects on tree vigor. Violent winds are very common, often reaching hurricane velocity of 73 miles per hour (117 km/h). Soils: Alpine larch commonly grows on slopes covered with granite or quartzite talus, not previously occupied by vascular plants. This tree will also establish itself in cracks between big boulders [2]. Soil development on alpine larch sites is extremely poor due to low temperatures and short growing seasons, which retard microbial and chemical activity [2,3]. The rocky shallow soils are generally very gravelly loams, ranging in pH from 3.9 to 5.7 [24]. General classification of alpine larch soils are in fragmental, and loamy skeletal families within the order Entisols (cryorthents) [27]. SUCCESSIONAL STATUS : Alpine larch is an intolerant seral species that will decrease when shaded by more shade-tolerant conifers [11]. This long-lived dominant often forms pure stands 500 to 1,000 feet (150-300 m) above the elevational limits of other conifers. Alpine larch is generally classified as an associate species within the whitebark pine, Engelmann spruce, subalpine fir, and mountain hemlock (Tsuga mertensiana) habitat types. In higher elevation sites, alpine larch is classified under the alpine larch/subalpine fir hts; while in lower elevation sites, it is categorized more broadly into the subalpine fir/smooth woodrush hts [2,23]. Alpine larch can be thought of as a pioneer species, establishing itself on rocky surfaces. It also proliferates after fire, avalanche, or other site disturbances. On some occasions, alpine larch will regenerate on burned areas within the subalpine fir zone, 330 to 490 feet (100-150 m) below its usual elevational limits [2]. This regenerative trend is more dominant on northern exposures and at high elevations [3]. At the highest timberline elevations, alpine larch fills a vacant niche representing the potential climax. Its ability to grow at higher elevations than other conifers relates to its superior resistance to winter desiccation [2]. SEASONAL DEVELOPMENT : The growing season for alpine larch lasts approximately 90 days. Bud development is triggered by rising mean air temperature to about 39 degrees Fahrenheit (4 deg C) and can be normally expected to begin the end of May. Shoot growth occurs mostly in July and progresses rapidly. The height growth of a small alpine larch will average approximately 0.6 inch (1.5 cm) a year during the first 25 years. Leaf fall and dormancy are controlled by photoperiod. Late summer drought, however, has been shown to induce early yellowing [3]. Alpine larch far outlives its associated conifer species and usually dies as a result of being windblown after pronounced heart rot. If lower limbs remain on the stump, the tree can remain alive for many more decades [3].


SPECIES: Larix lyallii
FIRE ECOLOGY OR ADAPTATIONS : Alpine larch is a thin-barked species easily damaged by fire [3,11,19]. It does not usually suffer from fire effects because the tree tends to occupy remote, rocky, cold sites where fire does not spread well [3,19]. Fire appears to have an important influence on the establishment of alpine larch by creating mineral soil seedbeds [5]. POSTFIRE REGENERATION STRATEGY : off-site colonizer; seed carried by wind; postfire years 1 and 2


SPECIES: Larix lyallii
IMMEDIATE FIRE EFFECT ON PLANT : On the occasion fire does reach alpine larch stands, the tree will not do favorably under those of high intensity. Pure stands of alpine larch, particularly if krummholz, have a high surface area that becomes extremely flammable. Low-intensity fires, however, may be beneficial to open stands by consuming ground debris, or by reducing insects and disease [2,5]. DISCUSSION AND QUALIFICATION OF FIRE EFFECT : NO-ENTRY PLANT RESPONSE TO FIRE : Being highly susceptible to fire, alpine larch's only defense seems to be isolation on high rocky sites, and long life spans which result in thick bark, self-pruning, and heavy seed crops. Seedling establishment is very successful on scarified sites because seedlings are able to anchor quickly and mature in barren conditions, while out-living competitors by hundreds of years [2,3]. DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : NO-ENTRY FIRE MANAGEMENT CONSIDERATIONS : NO-ENTRY

References for species: Larix lyallii

1. Arno, Stephen F. 1970. Ecology of alpine larch (Larix lyallii Parl.) in the Pacific Northwest. Missoula, MT: Univeristy of Montana. 264 p. Dissertation. [16708]
2. Arno, Stephen F. 1990. Larix lyallii Parl. alpine larch. In: Burns, Russell M.; Honkala, Barbara H., technical coordinators. Silvics of North America. Volume 1. Conifers. Agric. Handb. 654. Washington, DC: U.S. Department of Agriculture, Forest Service: 152-159. [13380]
3. Arno, Stephen F.; Habeck, James R. 1972. Ecology of alpine larch (Larix lyallii Parl.) in the Pacific Northwest. Ecological Monographs. 42: 417-450. [16451]
4. Bernard, Stephen R.; Brown, Kenneth F. 1977. Distribution of mammals, reptiles, and amphibians by BLM physiographic regions and A.W. Kuchler's associations for the eleven western states. Tech. Note 301. Denver, CO: U.S. Department of the Interior, Bureau of Land Management. 169 p. [434]
5. Carlson, Clinton E.; Arno, Stephen F.; Menakis, James. 1990. Hybrid larch of the Carlton Ridge Research Natural Area in western Montana. Natural Areas Journal. 10(3): 134-139. [13997]
6. Carlson, Clinton E.; Blake, George M. 1969. Hybridization of western and subalpine larch. Bulletin 37. Missoula, MT: University of Montana, School of Forestry, Montana Forest and Conservation Experiment Station. 12 p. [16968]
7. Carlson, Clinton E.; Cates, Rex G.; Spencer, Stanley C. 1991. Foliar terpenes of a putative hybrid swarm (Larix occidentalis x Larix lyallii) in western Montana. Canadian Journal of Forestry. 21: 876-881. [16707]
8. Colenutt, M. E.; Luckman, B. H. 1991. Dendrochronological investigation of Larix lyallii at Larch Valley, Alberta. Canadian Journal of Forest Research. 21: 1222-1233. [15687]
9. Cooper, Stephen V.; Neiman, Kenneth E.; Roberts, David W. 1991. (Rev.) Forest habitat types of northern Idaho: a second approximation. Gen. Tech. Rep. INT-236. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station. 143 p. [14792]
10. Eyre, F. H., ed. 1980. Forest cover types of the United States and Canada. Washington, DC: Society of American Foresters. 148 p. [905]
11. Fischer, William C.; Bradley, Anne F. 1987. Fire ecology of western Montana forest habitat types. Gen. Tech. Rep. INT-223. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station. 95 p. [633]
12. Garrison, George A.; Bjugstad, Ardell J.; Duncan, Don A.; [and others]. 1977. Vegetation and environmental features of forest and range ecosystems. Agric. Handb. 475. Washington, DC: U.S. Department of Agriculture, Forest Service. 68 p. [998]
13. Hitchcock, C. Leo; Cronquist, Arthur. 1973. Flora of the Pacific Northwest. Seattle, WA: University of Washington Press. 730 p. [1168]
14. Holland, W. D.; Coen, G. M., editors. 1982. Ecological (Biophysical) land classification of Banff and Jasper National Parks. Volume II: soil and vegetation resources. Publication No. SS-82-44. Edmonton, AB: The University of Alberta, Alberta Institute of Pedology. [Total pages unknown]. [17279]
15. Knudsen, Gerhard M. 1968. Chemotaxonomic investigation of hybridization between Larix occidentalis and Larix lyallii: A preliminary investigation. Missoula, MT: University of Montana. ? p. Thesis. [17111]
16. Knudsen, Gerhard M.; Arno, Stephen F.; Habeck, James R.; Blake, George M. 1968. Natural distribution of western larch (Larix occidentalis) and subalpine larch (Larix lyallii). Res. Note 7. Missoula, MT: University of Montana, School of Forestry, Montana Forest and Conservation Experiment Station. 4 p. [16991]
17. Kuchler, A. W. 1964. Manual to accompany the map of potential vegetation of the conterminous United States. Special Publication No. 36. New York: American Geographical Society. 77 p. [1384]
18. Lackschewitz, Klaus. 1991. Vascular plants of west-central Montana--identification guidebook. Gen. Tech. Rep. INT-227. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station. 648 p. [13798]
19. Leiberg, J. B. 1900. The Bitterroot Forest Reserve. U.S. Geological Survey, 20th Ann. Rep., Part V. 1: 317-428. [25093]
20. Little, Elbert L., Jr. 1979. Checklist of United States trees (native and naturalized). Agric. Handb. 541. Washington, DC: U.S. Department of Agriculture, Forest Service. 375 p. [2952]
21. Lyon, L. Jack; Stickney, Peter F. 1976. Early vegetal succession following large northern Rocky Mountain wildfires. In: Proceedings, Tall Timbers fire ecology conference and Intermountain Fire Research Council fire and land management symposium; 1974 October 8-10; Missoula, MT. No. 14. Tallahassee, FL: Tall Timbers Research Station: 355-373. [1496]
22. Patterson, Patricia A.; Neiman, Kenneth E.; Tonn, Jonalea. 1985. Field guide to forest plants of northern Idaho. Gen. Tech. Rep. INT-180. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station. 246 p. [1839]
23. Pfister, Robert D.; Kovalchik, Bernard L.; Arno, Stephen F.; Presby, Richard C. 1977. Forest habitat types of Montana. Gen. Tech. Rep. INT-34. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Forest and Range Experiment Station. 174 p. [1878]
24. Raunkiaer, C. 1934. The life forms of plants and statistical plant geography. Oxford: Clarendon Press. 632 p. [2843]
25. Richards, James Harlan. 1991. Ecophysiology of a deciduous timberline tree, Larix lyallii Parl. Edmonton, AB: The University of Alberta: v-vi. Dissertation abstract. [16706]
26. Shearer, Raymond C. 1961. A method of overcoming seed dormancy in subalpine larch. Journal of Forestry. July: 513-514. [16720]
27. U.S. Department of Agriculture, Soil Conservation Service. 1975. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. Agric. Handb. No. 436. Washington, DC. 754 p. [15931]
28. U.S. Department of Agriculture, Soil Conservation Service. 1982. National list of scientific plant names. Vol. 1. List of plant names. SCS-TP-159. Washington, DC. 416 p. [11573]