Index of Species Information

SPECIES:  Salix hastata


Introductory

SPECIES: Salix hastata
AUTHORSHIP AND CITATION : Esser, Lora L. 1992. Salix hastata. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: http://www.fs.fed.us/database/feis/ [].

ABBREVIATION : SALHAS SYNONYMS : S. walpolei (Cov. and Ball) Ball SCS PLANT CODE : SAHA COMMON NAMES : Halberd willow TAXONOMY : The currently accepted scientific name of Halberd willow is Salix hastata L. [1,2,7,12]. Salix farriae, formerly S. hastata var. farriae, is now recognized as a distinct species. Although there remains some confusion regarding the taxonomy of these two entities, their geographical distributions are distinctly different. Salix hastata is limited to Alaska, Yukon, and the District of Mackenzie. Salix farriae occurs from southern British Columbia and Alberta southward to Oregon, Idaho, Montana and Wyoming [7]. Recognized varieties of Salix hastata are as follows [12]: Salix hastata var. hastata L. Salix hastata var. subintegrifolia Flod. Salix hastata var. subalpina Anderss. Salix hastata var. alpestris Anderss. LIFE FORM : Shrub FEDERAL LEGAL STATUS : No special status OTHER STATUS : NO-ENTRY


DISTRIBUTION AND OCCURRENCE

SPECIES: Salix hastata
GENERAL DISTRIBUTION : In North America, Halberd willow occurs in northern Alaska, the mountains of central Alaska, including the Alaska range, and extreme northwestern Canada. It is most common near the Arctic Coast. Halberd willow also occurs in northern Europe and Asia, southward in the mountains of both [7,21]. ECOSYSTEMS : FRES23 Fir - spruce FRES44 Alpine STATES : AK NT YT BLM PHYSIOGRAPHIC REGIONS : NO-ENTRY KUCHLER PLANT ASSOCIATIONS : K015 Western spruce - fir forest K052 Alpine meadows and barren SAF COVER TYPES : 201 White spruce 202 White spruce - paper birch 203 Balsam poplar 204 Black spruce 217 Aspen 251 White spruce - aspen 252 Paper birch 253 Black spruce - white spruce 254 Black spruce - paper birch SRM (RANGELAND) COVER TYPES : NO-ENTRY HABITAT TYPES AND PLANT COMMUNITIES : Halberd willow is a common thicket-forming shrub on streambanks and moist slopes in the Arctic, extending to alpine regions and onto tundra [2,12]. In the boreal forest of interior Alaska, Halberd willow occurs primarily in willow thickets along small streams and is a pioneer species on river sandbars and glacial moraines. It is found occasionally in alpine sedge bogs [17,21]. Halberd willow also occurs in floodplain thickets on rivers and grows on newly exposed alluvial deposits that are periodically flooded [1,21].

MANAGEMENT CONSIDERATIONS

SPECIES: Salix hastata
IMPORTANCE TO LIVESTOCK AND WILDLIFE : In interior Alaska, willows (Salix spp.), are the most important source of browse for moose. Halberd willow is a lightly browsed species by moose and is considered an unimportant dietary component [17]. Willow shoots, catkins, leaves, and buds are eaten by numerous small mammals and birds [10]. PALATABILITY : In interior Alaska, Halberd willow is considered less palatable to moose than Alaska willow (S. alaxensis), littletree willow (S. arbusculoides), sandbar willow (S. interior), and tealeaf willow (S. planifolia ssp. pulchra) [17]. Palatability of willows increases as the season progresses [16]. NUTRITIONAL VALUE : NO-ENTRY COVER VALUE : NO-ENTRY VALUE FOR REHABILITATION OF DISTURBED SITES : Halberd willow is useful in stabilizing streambanks and providing erosion control on severely disturbed sites [9]. Willow species are the most important colonizers of disturbed sites in the Alaskan taiga because of their ability to produce root and root crown shoots, which provide for quick recovery [25]. On the North Slope of Alaska, large areas of riparian shrub river valleys were destroyed when the Trans-Alaska Pipeline System (TAPS) was constructed. The affected area had 12,300 acres (492 ha) of primary moose habitat prior to construction of TAPS, of which 2,825 acres (113 ha) or 23 percent were disturbed. Habitat restoration was not possible on 60 percent of the disturbed area, which had been mined below the level of the river. Three to four years after disturbance, natural regeneration had occurred on all disturbed sites within the impact area. Salix hastata and other willows colonized all moist silty areas and dry areas but not moist gravel areas. Site conditions affecting natural revegetation of disturbed areas were similar to those affecting riparian succession on areas not disturbed by construction [6]. OTHER USES AND VALUES : All willows produce salicin, which is closely related chemically to salicylic acid, the active ingredient in aspirin. Native Americans of the Yukon Territory used the chewed leave of willows for mosquito bites, bee stings, and stomach aches. The branches were used for muskrat traps, fish traps, hare traps, and ribs of birchbark canoes [11]. OTHER MANAGEMENT CONSIDERATIONS : Willow establishment along riparian zones is an effective management tool because of the importance of willows in stabilizing streambanks and providing erosion control on disturbed sites [10].

BOTANICAL AND ECOLOGICAL CHARACTERISTICS

SPECIES: Salix hastata
GENERAL BOTANICAL CHARACTERISTICS : Halberd willow is a native, multibranched, spreading shrub typically between 3 and 6 feet (1-2 m) tall [12,21]. It has small, simple, alternate, deciduous leaves. Male and female flowers occur on separate plants in 0.75- to 2-inch-long (1.5-5 cm), erect catkins [21]. Halberd willow has a remarkable characteristic of plasticity; its growth form adapts readily to a wide variety of habitats [10]. RAUNKIAER LIFE FORM : Phanerophyte REGENERATION PROCESSES : Sexual reproduction: Halberd willow is dioecious. The fruit is contained in a dehiscent capsule that releases many seeds that are dispersed by wind or water. Optimum seed production occurs between 2 and 10 years. Bees are the chief pollinating agents [10]. The seeds of Halberd willow are short-lived, germinating immediately on moist surfaces with high relative humidity, exposed mineral substrates, and in full sunlight. Germination is inhibited on sites with a continuous cover of tree litter [5,10]. Seed germination occurs over a broad temperature range, 41 to 77 degrees Fahrenheit (5-25 deg C). This appears to be a compensatory mechanism because of the short seed life [5,26]. This adaptation to a wide range of temperatures is particularly important in interior Alaska, where surface soil temperatures may vary over a relatively wide range [26]. Vegetative reproduction: Most willows are prolific sprouters. It is assumed that Halberd willow also sprouts from the root crown or stembase if aboveground stems are broken or destroyed by cutting, flooding, or fire [10]. Detached stem fragments form adventitious roots if kept moist [1,23]. SITE CHARACTERISTICS : In Alaska and northern Canada, Halberd willow is found in wet areas such as heaths, riverbeds, and streams and on floodplains frequently disturbed by flooding and the resulting erosion and siltation [1]. In interior Alaska, Halberd willow occurs along streambanks, areas formed by glacial drift, outwash deposition areas, and old river floodplains with rocky substrates [3,17]. Soils: Halberd willow grows best in moist, alluvial bottomlands but is also found in well-drained sandy or gravelly substrates. The general pH range for willows is 5.5 to 7.5. Halberd willow will tolerate moderately alkaline soils but does poorly in extremely acidic or alkaline conditions [10]. Growth of Halberd willow is severely reduced when water levels are maintained at or above the root crown for extended periods. Halberd willow is also shade intolerant and grows best in full sunlight [4,10]. Plant associates: Halberd willow is commonly associated with the following species: Barclay willow (Salix barclayi), Alaska willow, tealeaf willow, Richardson willow (S. lanata ssp. richardsonii), black cottonwood (Populus trichocarpa), alder (Alnus spp.), sedges (Carex spp.), and mosses (Polytrichum spp.) [17]. SUCCESSIONAL STATUS : Obligate Initial Community Species Halberd willow is frequently found in early seral plant communities that occupy from 2.5 to 250 acres (1-100 ha) along river systems of interior Alaska. Halberd willow is a pioneer species that becomes established after disturbances such as fire, logging, or recent alluvial deposits resulting from floodplain processes [24]. Floodplain willow communities are short-lived; thinleaf alder (Alnus incana ssp. tenuifolia) and balsam poplar (Populus balsamifera) establish within 5 years of initial willow colonization. By 20 to 30 years, poplars begin to overtop the brushy canopy and dominate. By this stage in succession, overstory shade has eliminated most Halberd willows because of its shade intolerance [23]. SEASONAL DEVELOPMENT : Halberd willow flowers in late spring or midsummer (May-June). The fruit ripens soon after flowering, followed by seed dispersal in late July and early August [21,26].

FIRE ECOLOGY

SPECIES: Salix hastata
FIRE ECOLOGY OR ADAPTATIONS : Information on Halberd willow's ability to sprout after fire is lacking. It is assumed that following top-kill by fire, this willow sprouts from the root crown like most other species of willow [14]. Halberd willow produces numerous, minute seeds that are dispersed by wind, and are important in colonizing recently disturbed areas [10]. POSTFIRE REGENERATION STRATEGY : Small shrub, adventitious-bud root crown Ground residual colonizer (on-site, initial community) Secondary colonizer - off-site seed

FIRE EFFECTS

SPECIES: Salix hastata
IMMEDIATE FIRE EFFECT ON PLANT : Information on the fire effects on Halberd willow is lacking. It is assumed that like most other willow species, Halberd willow is fire-tolerant and sprouts readily from the root or root crown after being top-killed by fire [14]. Severe fires can kill willows completely by removing soil organic layers and charring the roots. Less severe fires only top-kill plants [10]. DISCUSSION AND QUALIFICATION OF FIRE EFFECT : NO-ENTRY PLANT RESPONSE TO FIRE : Halberd willow's density probably increases shortly after burning. However, it is shade intolerant, and density will decline as young trees overtop it [21]. Halberd willow seeds need a nutrient-rich mineral seedbed to germinate. The chance of Halberd willow establishing after a fire lessens as available mineral soil seedbeds become occupied by faster growing herbaceous species and mosses [5]. Fire severity affects the mode of willow postfire recovery. Following light-severity fires most willows recover quickly, sending up new shoots from undamaged root crowns. Few, if any, seedlings establish following this type of fire because the partially consumed organic soil layers comprise an unfavorable seedbed. Following severe fire, however, the primary mode of recovery is seedling establishment. Severe fires that burn into organic soils kill willows, but expose mineral soils which provide excellent seedbeds [26]. DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : NO-ENTRY FIRE MANAGEMENT CONSIDERATIONS : Prescribed fire is widely used as a management tool to rejuvenate decadent willow stands and stimulate sprouting [10]. Early seral stage communities created by fire can increase the carrying capacity of winter range for moose in interior Alaska [25]. Recurring fires within some parts of the boreal forest have allowed aspen and willow to replace coniferous forests. The tendency of willows to expand quickly following fires and other disturbances and to form dense thickets inhibits natural regeneration of conifers. Prescribed burning can reduce initial competition from willow in areas to be planted with cultivated species [10].

REFERENCES

SPECIES: Salix hastata
REFERENCES : 1. Argus, George W. 1973. The genus Salix in Alaska and the Yukon. Publications in Botany, No. 2. Ottowa, ON: National Museums of Canada, National Museum of Natural Sciences. 279 p. [6167] 2. Brayshaw, T. Christopher. 1976. Catkin bearing plants of British Columbia. Occas. Pap. No. 18. Victoria, BC: The British Columbia Provincial Museum. 176 p. [6170] 3. Bliss, L. C.; Cantlon, J. E. 1957. Succession on river alluvium in northern Alaska. American Midland Naturalist. 58(2): 452-469. [14931] 4. Brunsfeld, Steven J.; Johnson, Frederic D. 1985. Field guide to the willows of east-central Idaho. Bulletin Number 39. Moscow, ID: University of Idaho; College of Forestry, Wildlife and Range Sciences; Forest, Wildlife and Range Experiment Station. 82 p. [6175] 5. Densmore, Roseann; Zasada, John. 1983. Seed dispersal and dormancy patterns in northern willows: ecological and evolutionary significance. Canadian Journal of Botany. 61: 3207-3216. [5027] 6. Densmore, R. V.; Neiland, B. J.; Zasada, J. C.; Masters, M. A. 1987. Planting willow for moose habitat restoration on the North Slope of Alaska, U.S.A. Arctic and Alpine Research. 19(4): 537-543. [6080] 7. Dorn, Robert D. 1975. A systematic study of Salix section Cordatae in North America. Canadian Journal of Botany. 53: 1491-1522. [5339] 8. Eyre, F. H., ed. 1980. Forest cover types of the United States and Canada. Washington, DC: Society of American Foresters. 148 p. [905] 9. 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] 10. Holloway, Patricia S.; Alexander, Ginny. 1990. Ethnobotany of the Fort Yukon region, Alaska. Economic Botany. 44(2): 214-225. [13625] 12. Hulten, Eric. 1968. Flora of Alaska and neighboring territories. Stanford, CA: Stanford University Press. 1008 p. [13403] 13. 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] 14. Lutz, H. J. 1956. Ecological effects of forest fires in the interior of Alaska. Tech. Bull. No. 1133. Washington, DC: U.S. Department of Agriculture, Forest Service. 121 p. [7653] 15. 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] 16. Machida, Steven. 1979. Differential use of willow species by moose in Alaska. Fairbanks, AK: University of Alaska. 97 p. Thesis. [15098] 17. Milke, Gary Clayton. 1969. Some moose-willow relationships in the interior of Alaska. College, AK: University of Alaska. 79 p. Thesis. [15801] 18. Olson, R. A.; Gerhart, W. A. 1982. A physical and biological characterization of riparian habitat and its importance to wildlife in Wyoming. Cheyenne, WY: Wyoming Game and Fish Department. 188 p. [6755] 19. Raunkiaer, C. 1934. The life forms of plants and statistical plant geography. Oxford: Clarendon Press. 632 p. [2843] 20. 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] 21. Viereck, Leslie A.; Little, Elbert L., Jr. 1972. Alaska trees and shrubs. Agric. Handb. 410. Washington, DC: U.S. Department of Agriculture, Forest Service. 265 p. [6884] 22. Viereck, Leslie A. 1973. Wildfire in the taiga of Alaska. Quaternary Research. 3: 465-495. [7247] 23. Viereck, Leslie A. 1975. Forest ecology of the Alaska taiga. In: Proceedings of the circumpolar conference on northern ecology; 1975 September 15-18; Ottawa, ON. Washington, DC: U.S. Department of Agriculture, Forest Service: 1-22. [7315] 24. Wolff, Jerry O. 1976. Utilization of hardwood browse by moose on the Tanana flood plain of interior Alaska. Res. Note PNW-267. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station. 7 p. [16870] 25. Wolff, Jerry O. 1978. Burning and browsing effects on willow growth in interior Alaska. Journal of Wildlife Management. 42(1): 135-140. [3500] 26. Zasada, J. C.; Viereck, L. A. 1975. The effect of temperature and stratification on germination on selected members of Salicaceae in interior Alaska. Canadian Journal of Forest Research. 5(2): 333-337. [6989]


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