Salix arctica Pall.
Arctic willow.
Salicaceae, willow family.
Fl. Ross. 1: 86. 1788.
Salix anglorum auct. non Cham.
Salix anglorum var.
antiplasta Schneid.
Salix anglorum var. araioclada
Schneid.
Salix anglorum var. kophophylla Schneid.
Salix
arctica subsp. crassijulis (Trautv.) Skvort.
Salix arctica
subsp. tortulosa (Trautv.) Hultén
Salix arctica var.
antiplasta (Schneid.) Fernald
Salix arctica var.
araioclada (Schneid.) Raup
Salix arctica var. brownei
Anderss.
Salix arctica var. kophophylla (Schneid.) Polunin
Salix arctica var. pallasii (Anderss.) Kurtz
Salix
arctica var. tortulosa (Trautv.) Raup
Salix brownei
(Anderss.) Bebb
Salix crassijulis Trautv.
Salix
hudsonensis Schneid.
Salix pallasii Anderss.
Salix
pallasii var. crassijulis (Trautv.) Anderss.
Salix
tortulosa Trautv.
Vegetative morphology. Plants shrubs; dwarf shrubs; 3–25 cm high; not colonial, or forming colonies by layering. Aerial stems decumbent, or prostrate, or erect. Branches yellow-brown, or yellowish, or grey-brown, or red-brown, or brownish; not glaucous, or thickly glaucous; glabrous, or glabrescent; epidermis not flaky. Branchlets yellow-brown, or red-brown, or violet; not glaucous, or thinly glaucous, or thickly glaucous; glabrous, or hairy; pilose, or villous; hairs sparse, or very dense; hairs spreading. Bud scale inner membrane free but not separating from outer membrane. Stipules absent, or present (caducous); leaf-like, or scale-like; apex acute. Petioles 2–35 mm long; glandular dots at the base of the leaf absent; deeply concave in cross-section, but margins not covering the groove; glabrous, or hairy; puberulent (if applicable). Leaf blade bases cuneate, or attenuate, or acute. Juvenile leaves yellowish green; glabrous, or hairy; abaxial surface villous (long, straight hairs pointing toward tip); hair sparse; hair white. Blades 10–85 mm long; 5.5–60 mm wide. Blades length-width ratio 1–3.6. Blades herbaceous, or leathery; elliptic (narrowly elliptic to subcircular), or circular, or oblanceolate, or obovate (to broadly obovate); revolute, or flat. Blades secondary veins protruding on adaxial and abaxial surfaces, or flat on adaxial surface, protruding on abaxial surface; arising along midrib. Blades adaxial surface shiny, or dull; glabrous, or hairy, or glabrescent. Blades adaxial surface hairs pilose (hairs near margin); sparse; white and translucent. Blades abaxial surface glaucous; glabrous, or hairy, or glabrescent (beard at tip). Blades abaxial surface hairs sparse. Blades abaxial surface hairs long-silky, or pilose. Blades abaxial surface hairs white, or translucent hairs; straight (typical), or wavy; spreading, or appressed. Blade margins glandular-dotted and entire; with submarginal glands, or with marginal glands; with teeth per cm 1–3. Blade margins with glandular hairs toward base only. Leaf apices obtuse, or rounded, or acute.
Reproductive morphology. Plants dioecious. Flowering stems present. Inflorescence a catkin. Catkins flowering with the opening of leaf buds; one to several catkins just below tip of previous year’s shoot. Male catkins densely flowered; 11–50 mm long; 5–18 mm wide; slender, or stout, or subglobose; peduncles 2–13 mm long; borne on a flowering branchlet; flowering branchlets 2–20 mm long. Female catkins densely flowered, or moderately densely flowered; 11–120 mm long; 8–18 mm wide; slender, or stout, or subglobose; peduncles 4–30 mm long; borne on a flowering branchlet; flowering branchlets 2–80 mm long. Floral bracts brown, or black (rarely light brown); widest at base, or widest at middle; 1.6–3.7 mm long; hairy all over. Floral bracts hairs sparse; straight (long). Floral bracts entire, or minute undulations (or with 2–3 undulations). Perianth absent. Flowers unisexual. Stamens 2; filaments glabrous. Anthers purple (rarely becoming yellowish); ellipsoid; axis straight; 0.4–0.9 mm long. Male flowers abaxial nectaries absent, or one; adaxial nectaries one; adaxial nectaries slender-rod, or broad-rod, or square; adaxial nectaries 0.5–1.2 mm long. Female flowers adaxial nectaries absent; unlobed; broad-rod, or ovate, or slender-rod; 0.4–1.8 mm long; longer than stipes, or equal to stipes (usually 1.5–4X, rarely equal). Stipes 0.2–1.6 mm long. Ovaries inverse club-shaped, or pear-shaped; ovary abruptly tapering to style, or slightly bulged at the base of the style, or gradually tapering to style; hairy; villous. Ovary hairs dense, or sparse, or moderately dense; white, or translucent; spreading; wavy; flattened (sometimes refractive). Styles 0.6–2.2 mm long. Stigmas slender-cylindrical (sometimes stout); lobes 0.36–0.56–0.88 mm long. Ovules 10–18. Fruit a capsule. Fruit 4–9 mm long; hairy, or glabrescent (sometimes glabrescent).
Chromosome information. 2n = 76 and 114. 76 (4x).
- Holmen (1952 Greenland); Mosquin and Hayley (1966 northern Canada, 2n =
c.76); Johnson and Packer (1968 northwestern Alaska); Suda and Argus (1969
Alaska); Löve et al. (1971 western North America, as S. cf.
arctica in Löve and Löve 1975); Zhukova and Petrovsky (1980
western Chukotka); Petrovsky and Zhukova (1983 north eastern Asia); Dawson in
Argus (1997 North America).
c. 100. - Zhukova (1969 north eastern Asia);
Petrovsky and Zhukova (1983 north eastern Asia).
114 (6x). -
Zhukova et al. (1973 northe eastern Asia); Löve and Löve in Löve
(1975c Iceland, as S. cordifolia, see comment above under S.
glauca, 1982); Petrovsky and Zhukova (1983, 1987 NE As); Suda and Argus
(1969 Alaska, two counts).
c.120. - Sokolovskaya and Strelkova (1948a
southern Siberia, Altai).
190 (10x). - Löve and Löve (1956
Iceland, as S. callicarpaea, see comment above). Ploidy levels recorded 4
and 6x.
Distribution. Northern hemisphere distribution: Greenland, Canada, United States, Eurasia. Arctic Islands: Baffin, Devon, Ellesmere, Axel Heiberg, Parry Islands, Cornwallis, Banks, Victoria, Prince of Wales, Somerset, King William, Southampton, Coats.
Ecology and habitat. Habitats: A ubiquitous dwarf shrub often forming prostrate mats spreading from a central stem. It may occur on sparsely vegetated surfaces or spreading over dense tundra vegetation. It grows in most arctic habitats including hummocks in wet sphagnum bogs and sedge meadows, polygonal tundra, solifluction slopes, snow beds, margins of pools, beach ridges, shaley and gypsum ridges, gneissic cliffs, colluvial slopes, talus slopes, imperfectly drained calcareous silty till, muddy salt flats, frost-heaved clay polygons, dry calcareous gravel, and coarse sandy soil. Plants are often heavily browsed by muskox and arctic hares. Elevation 0–700 m.
Indigenous knowledge. Inuit name Suputit - the flowers of
willow gone to seed. Uqaujait, young willow leaves that were eaten with
pices of blubber. (Ootoova, 2001).
According to Rodahl (1944) the buds and
leaes of arctic willow are excetionally rich in Vitamin C.
Notes. Salix arctica is a dwarf shrub, sometimes with long
trailing branches that root where they touch the surface. Leaf size and shape
are highly variable but the abaxially surface of the leaves is always glaucous
and usually clothed with long, straight, appressed hairs that may persist as a
‘beard’ at the tip, the margins are entire. Floral bracts are dark
brown and clothed with long, straight hairs.
This circumpolar species is
morphologically polymorphic and nomenclaturally confused. Many botanists
studying the flora of the Arctic Archipelago have collected what they thought
were two or three species of Salix to find on their return that they were
all S. arctica. Some taxonomists (Hultén 1967, 1971) have
recognized three subspecies in S. arctica. (1) subsp. arctica
(circumpolar from Iceland and the Faeroe Islands across northern Russia, Alaska
and Canada to Greenland, south to the Hudson Bay shores of Ontario and the
Gaspé Peninsula.), (2) subsp. crassijulis (a North Pacific race
ranging from Kamchatka and the Russian Far East to the Aleutian Islands, south
central and South-eastern Alaska along the coast to northern Washington), and
(3) subsp. torulosa (ranging from the mountains of Central Asia to
Kamtchatka and the Bering Straits, the Brooks Range and the Rocky Mountains in
Alaska, south in the cordillera to southern British Columbia and Alberta). While
the phytogeographic pattern of these three races is appealing they are actually
very difficult or impossible to separate morphologically. Argus (1973) presented
evidence that the latter two subspecies were environmental modifications of one
species. He reported that robust plants in the Glacier Bay area of South-eastern
Alaska (S. arctica subsp. crassijulis) were associated with
nitrogen-rich Alnus thickets whereas small plants (S. arctica
subsp. torulosa) from the same area were growing on open moraine. Others
have also reported environmental modification of S. arctica. Saville
(1964) noted that depauperate specimens occurred in depressions behind beach
ridges where they may be immersed in years of high water. Soper and Powell
(1985) observed that this species varied considerably according to ecological
and edaphic conditions. Dawson (1987) showed that the female-biased sex ratios
in S. arctica is environmentally controlled (female plants are
significantly over-represented in mesic-wet, more fertile, low soil temperature
sites, whereas, male plants are predominant in drier, less fertile sites). In
light of this evidence the possibility that the complex morphological
variability within S. arctica may be ecophenic or ecotypic deserves
study. Other characters cited to separate subsp. torulosa (Hultén
1971) including leaf shape and floral bract colour do not withstand scrutiny
(Argus 1973, Raup 1959). The morphological variability within S. arctica,
although striking, does not seem to reflect taxonomic differences.
Age of
Salix arctica: about 130 years, Franz Joseph Fjord, East Greenland
(Gelting 1934); in the Mesters Vig area of East Greenland (King Oscars Fjord)
Raup (1965) reported that most specimens were about 60 years old with one
reaching 180 and another 236 years; the oldest Canadian material is 85 years
from Lake Hazen, Ellesmere Island (Savile 1979).
In northern Greenland
Salix arctica is one of the primary foods for muskox, arctic hare, and
collared lemming (Klein and Bay 1991).
Hybrids
Salix
arctica × arctophila (Polunin 1940). There are a number of
putative hybrids in Canadian Museum of Nature from Baffin and Ellesmere islands.
These plants have leaves and branchlets almost glabrous as in S.
arctophila, but bearing only a few long hairs, and ovaries with flattened,
refractive hairs as in S. arctica, not ribbon-like as in S.
arctophila. On Bylot Island, Drury (1962: 88–89) reported collecting
material that resembled S. arctophila but which intergraded with S.
arctica. These specimens need to be restudied.
Representative specimens:
Soper, J.D. 122106, Baffin Island, Panguirtung Fjord. 26 July 1924. CAN
46583; Wynne-Edwards, V.C. Baffin Island, Head of Clyde Inlet. 11 July
1950. CAN 283881; Polunin, N. 2376. Baffin Island, Cape Dorset. 15 June
1924. CAN 46516; Soper, J.D. 132178. Baffin Island, Head of Kinga Fjord.
31 July 1924. CAN 46520; Malte, M.O. s.n. Ellesmere Island, Craig
Harbour. 2 Aug. 1927. CAN 46377; Malte, M.O. 118599. Ellesmere Island,
Dundas Harbour. 27 July 1927. CAN 46381.
Salix arctica × S.
glauca (Argus 1965, 1973, Bay 1992). In 1965 Argus wrote, ‘This hybrid
is characterized by various combinations of the characteristics of S.
arctica and S. glauca. The S. glauca
characteristics include erect habit, leaves less oblanceolate and without the
attenuate base of S. arctica, shorter petioles, bracts light-colored with
shorter wavy trichomes [hairs], and a divided style. The S. arctica
characteristics include prostrate habit, pruinose [glaucous] stems and buds,
sparse branchlet-pubescence, dark-colored bracts with long, straight trichomes,
leaves with long straight trichomes on the lower [abaxial] surface projecting in
a ‘beard’ at the apex, capsules reddish with long stigmas, and dark
colored anthers.’ Specimens identified as hybrids combine these characters
in various ways. On Baffin Island the hybrid is difficult to recognize because
there S. glauca and S. arctica so converge in their morphology
that the recognition of intermediates is difficult.
Illustrations. • Habit. Salix arctica: plant growing on stony gravel. Photograph taken at Iqaluit, Baffin Island, Nunavut by Jack Gillett 22 July 1982. Voucher specimen: Jack Gillett 18992, CAN. • Habit. Salix arctica: plant forming a prostrate mat on a lakeshore. Photograph taken at Lake Hazen, Ellesmere Island, Nunavut, by Lynn Gillespie, 11 Aug. 1995. • Habit. Salix arctica: plant forming a prostrate mat on a glacial moraine. Photograph taken at Glacier Bay, Alaska, 29 June 1967. • Habit. Salix arctica: plant growing in rocks. Capsules have opened releasing seeds surrounded by hairs (fluff). Photograph taken at Alexandra Fiord, Ellesmere Island, Nunavut, by Lynn Gillespie, 30 July 1991. • Habitat. Salix arctica: habitat. Photo taken at Cambridge Bay, Victoria Island, Nunavut, by Laurie Consaul. Voucher specimen: Laurie Consaul and Lynn Gillespie 1137, CAN. • Close-up of plant. Salix arctica: Photo taken in the N.W.T. Aiken 97–021. • Close-up of female flowering plant. Salix arctica: close-up of female flowering plant. Photo taken at Iqaluit, Baffin Island, Nunavut by Aiken, 30 Aug. 1997, Voucher specimen: Aiken and Cheryl McJannet, 97021, CAN. • Close-up of plant. Salix arctica: close-up of plant with broadly elliptic leaves. The ovaries vary in colour from yellow (shown here) to red or even green. Photograph taken at Glacier Bay, Alaska, 29 June 1967. • Close-up of plant. Salix arctica: close-up of the plant with oblanceolate leaves. Photograph taken at Glacier Bay, Alaska, 29 June 1967. • Close-up of male catkin. Salix arctica: close-up of a male catkin. Catkins are densely flowered, the leaves on the flowering branchlet show the long "beard" of hairs at the tip. Photograph taken at Sachs Harbour, Banks Island, N.W.T. by Jack Gillett, 22 July 1982. Voucher specimen: Jack Gillett, 18865, CAN. • Female catkins. Salix arctica: Female catkins are erect and densely flowered. Photo taken by Donald Gunn; slide number: S84–5377, Photo Library, Canadian Museum of Nature. • Close-up of female catkin. Salix arctica: Female catkin with red styles and stigmas, densely hairy ovaries, and floral bracts with long, straight hairs. Photograph taken by Donald Gunn; slide number: S84–5379, Photo Library, Canadian Museum of Nature. • Close-up of female catkin. Salix arctica: Female catkins are densely flowered, the leaves on the flowering branchlet show the long "beard" of hairs at the tip. Photograph taken at Iqaluit, Baffin Island, Nunavut, by Jack Gillett, 22 July 1982. Voucher specimen: Jack Gillett, 18992, CAN. • Line drawing. Salix arctica: A. Male catkins are borne on short, leafy flowering branchlets. B. Male flowers have 2 stamens, a floral bract with long straight hairs, and a single nectary. C. A female catkin borne on a short, leafy flowering branchlet. The vegetative shoot bears elliptic to broadly elliptic leaves. D. Female flowers have villous ovaries, a long style, a long-hairy floral bract, and a single floral nectary that is longer than the stipe. • Arctic Island Distribution.
Cite this publication as: ‘S.G. Aiken, M.J. Dallwitz, L.L. Consaul, C.L. McJannet, L.J. Gillespie, R.L. Boles, G.W. Argus, J.M. Gillett, P.J. Scott, R. Elven, M.C. LeBlanc, A.K. Brysting and H. Solstad. 1999 onwards. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. Version: 29th April 2003. http://www.mun.ca/biology/delta/arcticf/’. Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993, 1995, 2000) should also be cited (see References).
