Flora of the Canadian Arctic Archipelago
English: Rock willow, hairy willow,
French: Saule pubescent.
Salicaceae, Willow family.
Published in Fl. Amer. Sept. 2: 610. 1814.
Type: Canada: Labrador, probably 1765, leg. Societ. Unit. Frat. [Moravian missionaries], selected by Dorn, Phytologia 77: 94. 1994. Lectotype: BM.
Synonymy. Salix leiolepis Fernald, Rhodora 16: 178. 1914.
Salix vestita Pursh var. leiolepis (Fernald) Argus, Can. J. Bot. 43: 1024. 1965.
Salix vestita Pursh β (var.) erecta Andersson, in DC. Prodr. 16(2): 300. 1868.
Salix vestita Pursh var. psilophylla Fernald and H. St. John, Victoria Mus. Mem. 120: 44. 1922.
Vegetative morphology. Plants 2–150 cm high; shrubs; low shrubs, or mid shrubs; not colonial. Aerial stems erect. Branches red-brown, or brownish; not glaucous; hairy, or glabrous, or glabrescent; hairs villous, or long-silky. Branchlets yellow-brown, or grey-brown; not glaucous; hairy; pilose, or villous, or with long-silky hairs. Branchlet hairs sparse, or moderately dense; spreading. Buds arctica-type. Leaves present; distributed along the stems; alternate; dying annually and non-persistent. Stipules present, or absent; on first leaves rudimentary, or absent; on leaves formed later in the season rudimentary. Petioles 2–8 mm long; shallowly concave in cross section, or deeply concave in cross section; hairy, or glabrous, or glabrescent; pubescent. Juvenile leaves yellowish green; hairy; abaxial surfaces hairs long-silky; abaxial hairs very dense; abaxial hairs white, or grey. Leaf blade bases obtuse, or rounded (subcordate). Blades 18–67 mm long, length-width ratio 1.1–2.3, 10–40 mm wide, elliptic (broadly) or obovate (or subcircular). Blade adaxial surface shiny, glabrous or hairy, hairs long-silky, hairs sparse, hairs white, or translucent. Blade abaxial surface glaucous, hairy, hairs villous or long-silky, hairs moderately dense or very dense or sparse, hairs white, hairs straight, hairs appressed or spreading. Blade margins strongly revolute. Blade margins entire and glandular-dotted or crenate, with teeth all around the blade, with teeth per cm 3–12; apices obtuse, or rounded, or retuse.
Reproductive morphology. Plants dioecious. Inflorescences catkins. Pedicels absent. Catkins arising from sub-apical buds; flowering as leaves emerge. Male catkins 13–48 mm long; 4–6.5(–8) mm wide; slender, or stout; peduncles 3–8 mm long; borne on a flowering branchlet (terminating normal vegetative shoots); flowering branchlets 3–27(–47) mm long. Female catkins 18–56 mm long; 4–10 mm wide; slender, or stout; peduncles 4–12 mm long; borne on a flowering branchlet (terminating normal vegetative shoots); flowering branchlets 3–27(–40) mm long. Floral bracts tawny; 0.8–1.6 mm long; hairy all over; hairs very dense; hairs straight; apices rounded; apices entire. Flowers unisexual. Sepals absent. Petals absent. Stamens 2; stamen filaments hairy on lower half. Anthers purple becoming yellow; ellipsoid, or sub-globose; 0.3–0.5 mm long. Male flowers abaxial nectaries present. Male flowers adaxial nectaries narrowly oblong; 0.5–1.2 mm long; nectaries distinct, or connate and cup-shaped. Female flowers abaxial nectaries present. Female flowers adaxial nectaries narrowly oblong, or oblong, or ovate (almost filiform); 0.7–1.4 mm long; shorter than stipes, or equal to stipes, or longer than stipes; nectaries distinct, or connate and cup-shaped. Ovary carpels 2. Stipes 0.4–1.2 mm long. Ovaries pear-shaped, or inverse turnip-shaped; abruptly tapering to style; hairy; short-silky. Ovary hairs very dense; white; appressed, or spreading; straight, or wavy; cylindrical. Styles partially fused (almost free to base), or free; 0.2–0.4 mm long. Stigma lobes 0.2–0.36 mm long. Ovules per ovary 13–15. Fruit a capsule; 3–5 mm long; hairy.
Chromosome information. 2n = 38.
(2n) (2x) = 38. Taylor and Brockmann (1966, western Canada); Hedberg (1967, northern Canada); Dorn (1975, North America); Löve and Löve (1975, in Löve 1982a, Churchill, Manitoba).
Ploidy levels recorded 2x.
Ecology and habitat. In reporting this species from the Arctic Archipelago, Polunin (1940) writes, "Rare even on Akpatok [Island], where it occurs in sheltered valleys that have a good snow-covering in winter, growing best in damp late-snow depressions, but even then remaining more or less prostrate.".
North American distribution. Northern Quebec, Labrador. Range in the Canadian Arctic Archipelago limited. Low Arctic. Arctic islands: Akpatok Island.
Northern hemisphere distribution. North American. Labrador Hudson Bay.
General notes. Salix vestita is an erect, shrubby relative of S. reticulata. Its leaves and branchlets, however, have distinct and permanent long silky hairs. In the Arctic Archipelago, this species occurs only on Akpatok Island in Ungava Bay. The only known collections (in the British Museum) were made by Nicholas Polunin in about 1933 (Polunin 1934).
Illustrations. • Close-up of plant. Branch of female plant. Quebec, Ile des Foreurs, Clearwater Lake. 12 July, 1983. G.W. Argus and P. Dumas 11050. CAN 492791. • Close-up of female catkins and hairs on leaves. Female catkins with short-silky hairs on ovaries and broadly elliptic leaves that have long and silky hairs on the abaxial surface. Quebec, Ile des Foreurs, Clearwater Lake. 12 July, 1983. G.W. Argus and P. Dumas 11050. CAN 492791. • Arctic Island Distribution.
This publication is available on the internet (posted May 2011) and on CD-ROM (published in 2007). These versions are identical in content, except that the errata page for CD-ROM is accessible on the main index page of the web version.
Recommended citation for the web-based version of this publication: Aiken, S.G., Dallwitz, M.J., Consaul, L.L., McJannet, C.L., Boles, R.L., Argus, G.W., Gillett, J.M., Scott, P.J., Elven, R., LeBlanc, M.C., Gillespie, L.J., Brysting, A.K., Solstad, H., and Harris, J.G. 2007. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. NRC Research Press, National Research Council of Canada, Ottawa. http://nature.ca/aaflora/data, accessed on DATE.
Recommended citation for the CD-ROM version of this publication: Aiken, S.G., Dallwitz, M.J., Consaul, L.L., McJannet, C.L., Boles, R.L., Argus, G.W., Gillett, J.M., Scott, P.J., Elven, R., LeBlanc, M.C., Gillespie, L.J., Brysting, A.K., Solstad, H., and Harris, J.G. 2007. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. [CD-ROM] NRC Research Press, National Research Council of Canada, Ottawa..