Salix reticulata |
Salix glauca |
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net-leaf willow, net-vein willow, netted willow |
glaucous willow, gray willow, gray-leaf willow, grey-leaf willow |
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Habit | Plants 0.03–0.15 m, (dwarf, forming clones by layering). | Plants 0.2–6 m, not clonal. | ||||||||||||
Stems | trailing; branches and branchlets yellow-brown or red-brown, glabrous. |
erect or decumbent; branches brownish, yellow-brown, gray-brown, or red-brown, villous or pilose to glabrescent; branchlets yellow-brown or red-brown, sparsely to densely villous or tomentose to glabrescent. |
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Leaves | stipules absent or rudimentary; petiole 3–46 mm, (sometimes glandular distally); largest medial blade amphistomatous or hemiamphistomatous, (2 pairs of secondary veins arising at or close to base, arcing toward apex), oblong, broadly oblong, broadly elliptic, subcircular, or circular, (8–)12–66 × 8–50 mm, 1–1.5 times as long as wide, base convex, rounded, subcordate, or cordate, margins slightly revolute, entire or crenulate (glandular-dotted), apex rounded, convex, or retuse, abaxial surface sparsely long-silky to glabrescent, adaxial (venation deeply impressed), slightly or highly glossy, glabrous or pilose; proximal blade margins entire; juvenile blade glabrous. |
stipules (marcescent or not), foliaceous or rudimentary on early and late ones; petiole (usually deeply to shallowly grooved adaxially), 1–27 mm, (much longer than subtended bud); largest medial blade usually hypostomatous, sometimes hemiamphistomatous or amphistomatous, usually narrowly elliptic, elliptic, usually oblanceolate or obovate, sometimes narrowly oblong or obovate, 27–82 × 6–39 mm, 1.4–4.8 times as long as wide, base usually cuneate or convex, sometimes rounded, rarely subcordate, margins slightly revolute or flat, usually entire, apex acute, acuminate, convex, or rounded, abaxial surface densely villous or villous-silky, tomentose, short- or long-silky, or pilose, hairs usually wavy or straight, sometimes curved, adaxial usually slightly glossy, sometimes dull, moderately densely villous, pilose, or long-silky to glabrescent; proximal blade margins entire or serrulate; juvenile blade sparsely or densely villous, tomentose, or long-silky abaxially. |
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Staminate flowers | abaxial nectary 0.5–0.9 mm, adaxial nectary oblong or ovate, 0.5–1 mm, nectaries connate and cup-shaped; filaments distinct, hairy on proximal 1/2 or throughout; anthers ellipsoid or globose, 0.3–0.4 mm. |
abaxial nectary 0.1–1 mm, adaxial nectary narrowly oblong, oblong, square, ovate, or flask-shaped, 0.5–1.3 mm, nectaries distinct, or connate and cup-shaped; filaments distinct or slightly or partly connate, glabrous, or hairy on proximal 1/2; anthers 0.4–0.8 mm. |
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Pistillate flowers | abaxial nectary (0–)0.3–0.5 mm, adaxial nectary narrowly oblong, 0.5–1 mm, equal to or longer than stipe, nectaries distinct or connate and cup-shaped; stipe 0–0.8 mm; ovary pyriform or ovoid, short-silky, hairs flattened, beak abruptly tapering to styles; ovules 8–18 per ovary; styles connate to distinct 1/2 their lengths, 0.2–0.3 mm; stigmas flat, abaxially non-papillate with rounded tip, broadly cylindrical, or 2 plump lobes, 0.2–0.26–0.36 mm. |
abaxial nectary absent, adaxial nectary usually narrowly oblong, oblong, or ovate, sometimes flask-shaped, 0.4–1.8 mm, shorter to longer than stipe; stipe 0.3–2.8 mm; ovary pyriform or obclavate, densely villous, tomentose, short-silky, or pubescent, beak usually gradually tapering to styles, sometimes gradually tapering to or slightly bulged below styles; ovules 6–22 per ovary; styles connate to distinct 1/2 their lengths or more, 0.3–1.6 mm; stigmas flat, abaxially non-papillate with rounded tip, or slenderly or broadly cylindrical, 0.2–0.8 mm. |
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Capsules | 4.5–5 mm. |
4.5–9 mm. |
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Catkins | staminate 11–54 × 4–9 mm, flowering branchlet 2–28 mm; pistillate densely flowered (more than 6 flowers), slender or stout, 11–79 × 3–8 mm, flowering branchlet 2–37 mm; floral bract tawny, 0.8–1.8 mm, apex rounded to retuse, entire, abaxially glabrous. |
staminate 14–53 × 5–17 mm, flowering branchlet 1–25 mm; pistillate densely to sometimes loosely flowered, slender, stout, subglobose, or globose, 15–83 × 7–21 mm, flowering branchlet 2–37 mm; floral bract tawny, brown, bicolor, or greenish, 1–3.4 mm, apex convex or rounded, entire, abaxially hairy, hairs wavy, crinkled, or straight. |
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2n | = 38. |
= 76, 95, 114, 152. |
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Salix reticulata |
Salix glauca |
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Phenology | Flowering early Jun-mid Aug. | |||||||||||||
Habitat | Arctic-alpine, polygonal tundra, dry tussock tundra, partially stabilized sand dunes, sedge meadows, Dryas tundra on alpine cliffs and ledges, snowbeds, stabilized talus slopes, white spruce woods, treed bogs | |||||||||||||
Elevation | 0-3500 m (0-11500 ft) | |||||||||||||
Distribution |
AK; CO; AB; BC; MB; NL; NT; NU; ON; QC; SK; YT; Europe; Asia (Chukotka, Russian Far East, arctic, e Siberia, Spitzbergen)
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AK; CO; MT; NM; OR; UT; WA; WY; AB; BC; MB; NS; NT; NU; ON; QC; SK; YT; Eurasia (China [Altay Shan], Chukotka, Mongolia, Novaya Zemlya, Russian Far East, Sakhalin, Scandinavia, arctic, e, w Siberia)
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Discussion | The reported occurrence of Salix reticulata in Colorado (R. D. Dorn 1997) needs further study. Salix reticulata occurs in Europe in northern Scotland, northern Scandinavia, the Alps and other European mountains, and arctic Eurasia. The species is circumpolar except for Greenland and Iceland. A population of Salix reticulata on the Queen Charlotte Islands, with consistently glabrous ovaries, was named subsp. glabellicarpa. Some southeastern Alaska populations have plants with glabrous, partially hairy, and completely short-silky ovaries growing together. The possibility that subsp. glabellicarpa may be a hybrid or a simple mutation needs study. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Varieties 5 (4 in the flora). Occurrence of Salix glauca is disjunct in western Siberia; var. glauca is known from Scandinavia. Salix glauca is ubiquitous, highly polymorphic, and polyploid. It appears to have four major variations that are treated in different ways. European floras have treated it as an undivided polymorphic species(A. K. Skvortsov 1999), as several distinct species (K. H. Rechinger 1964b), or as comprising several subspecies (Rechinger 1993; G. W. Argus et al. 1999; B. Jonsell and T. Karlsson 2000+, vol. 1). In North America, Argus (1965) treated the four central tendencies as widely intergrading “phases” of a single species, later adopting varietal rank, whereas E. Hultén (1968) recognized them as subspecies. In view of the fact that the four elements are confluent over wide areas, there may be some merit in recognizing them as informal phases, but varietal rank is used here. All specimens from Iceland named Salix glauca are S. arctica and those from Svalbard, Norway, are S. lanata Linnaeus. The major reason for the high variability within Salix glauca seems to be high, and probably recurrent, polyploidy. Tetraploids, pentaploids, hexaploids, and octoploids are known in the species, and two of the subspecies include three ploidal levels. There also are intergrading geographical variations that are the basis for the recognition of infraspecific taxa. Hybrids: Salix glauca forms natural hybrids with S. arctica, S. arctophila, S. ballii, S. barclayi, S. boothii, S. brachycarpa, S. eastwoodiae, S. myricoides, S. niphoclada, S. pedicellaris, and S. planifolia. The following key will help identify the varieties, but there are extensive areas of overlap among them and many intermediates. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 7, p. 65. | FNA vol. 7, p. 89. | ||||||||||||
Parent taxa | Salicaceae > Salix > subg. Chamaetia > sect. Chamaetia | Salicaceae > Salix > subg. Chamaetia > sect. Glaucae | ||||||||||||
Sibling taxa | ||||||||||||||
Subordinate taxa | ||||||||||||||
Synonyms | S. reticulata var. gigantifolia, S. reticulata subsp. glabellicarpa, S. reticulata var. semicalva | |||||||||||||
Name authority | Linnaeus: Sp. Pl. 2: 1018. (1753) | Linnaeus: Sp. Pl. 2: 1019. (1753) | ||||||||||||
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