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mountain willow, Scouler willow, Scouler's willow

satiny willow

Habit Shrubs or trees, 1–10(–20) m. Stems: branches gray-brown, yellow-brown, or red-brown, not glaucous, glabrous or tomentose; branchlets yellow-green or yellow-brown, sparsely to densely villous, tomentose, or velvety. Shrubs, 0.5–6 m, (sometimes forming clones by stem fragmentation).
Stems

branches (highly to ± brittle at base), red-brown, violet or yellow-brown, usually strongly glaucous, glabrescent;

branchlets yellow-brown or red-brown, (usually strongly glaucous), glabrous or densely to sparsely pubescent or tomentose, (buds caprea-type).

Leaves

stipules absent, rudimentary, or foliaceous on early ones, foliaceous on late ones, (1–16 mm), apex acute or acuminate;

petiole convex to flat adaxially, 2–13 mm, velvety or villous adaxially;

largest medial blade usually oblanceolate, sometimes narrowly elliptic, elliptic or obovate, 29–100 × 9–37 mm, 1.7–3.9 times as long as wide, base cuneate or convex, margins strongly to slightly revolute or flat, entire, remotely serrate, crenate, or sinuate, (glands submarginal or epilaminal), apex acuminate, convex, or rounded, abaxial surface glaucous, sparsely to densely short- to long-silky or woolly, hairs (white, sometimes also ferruginous), wavy or straight, adaxial slightly glossy, pilose or moderately densely short-silky, midrib velutinous or villous, (hairs white, sometimes also ferruginous);

proximal blade margins entire, serrulate, or crenulate;

juvenile blade reddish or yellowish green, sparsely to densely villous, short- or long-silky abaxially, hairs white, sometimes also ferruginous.

stipules absent or rudimentary on early ones, rudimentary, absent, or foliaceous on late ones;

petiole convex to flat, or shallowly grooved adaxially, 3–6.3–14 mm, (sometimes dark spherical glands distally), glabrous or pubescent adaxially;

largest medial blade linear, lorate, or narrowly elliptic 40–79–123 × 6–12–20 mm, (2.3–)4.2–7.2–11.3 times as long as wide, base convex or cuneate, margins strongly or slightly revolute, entire, sinuate or sometimes crenulate, (glands submarginal or epilaminal), apex acuminate to acute, abaxial surface glaucous (sometimes obscured by hairs), densely villous, short-silky, woolly, or tomentose to glabrescent, hairs (white, sometimes also ferruginous), straight or wavy, adaxial slightly to highly glossy, glabrous, sparsely villous or pubescent (hairs white, sometimes also ferruginous);

proximal blade margins entire;

juvenile blade reddish or yellowish green, densely tomentose, short-silky, pubescent, or glabrous abaxially, hairs white, sometimes also ferruginous.

Staminate flowers

adaxial nectary oblong or square, 0.4–0.9 mm;

filaments distinct, glabrous or hairy on proximal 1/2;

anthers purple turning yellow, ellipsoid to shortly cylindrical, 0.7–1.2 mm.

adaxial nectary oblong or narrowly oblong, 0.6–1 mm;

filaments distinct, glabrous or hairy basally;

anthers purple turning yellow, ellipsoid, 0.4–0.6 mm.

Pistillate flowers

adaxial nectary oblong or square, 0.2–0.8 mm, shorter than stipe;

stipe 0.8–2.3 mm;

ovary pyriform or obclavate, densely long-silky, beak slightly bulged below styles;

ovules 10–18 per ovary;

styles 0.2–0.6 mm;

stigmas slenderly cylindrical, 0.4–0.82–1.04 mm.

adaxial nectary oblong to depressed-ovate, 0.3–1 mm, shorter than or equal to stipe;

stipe 0.5–1.1 mm;

ovary pyriform, short-silky, beak sometimes slightly bulged below styles;

ovules 10–18 per ovary;

styles 0.6–1.5 mm;

stigmas slenderly cylindrical, 0.4–0.55–0.76 mm.

Capsules

4.5–11 mm.

3.5–6.5 mm.

Catkins

flowering before leaves emerge; staminate stout or subglobose, 18–40.5 × 8–22 mm, flowering branchlet 0–4 mm; pistillate very densely flowered, slender or stout, 18–60(–90 in fruit) × 10–22 mm, flowering branchlet 0–8 mm;

floral bract brown, black, or bicolor, 1.5–4.5 mm, apex rounded or acute, abaxially hairy, hairs straight.

flowering before leaves emerge; staminate stout, 20–39 × 7–20 mm, flowering branchlet 0–2 mm; pistillate densely flowered, slender, stout, or subglobose, 19–65(–80 in fruit) × 7–17 mm, flowering branchlet 0–7 mm;

floral bract tawny, brown, or black, 1–2.6 mm, apex acute, convex, or rounded, abaxially hairy, hairs straight.

2n

= 76.

= 38.

Salix scouleriana

Salix pellita

Phenology Flowering late Feb-mid Jun. Flowering late Apr-late Jun.
Habitat Dry conifer forests, mature woods on edges of streams and lakes, treed bogs, meadows, subalpine slopes, springs, pine barrens, openings in old burns, arroyos and disturbed sites, sandy, silty-clay, or gravelly, igneous substrates Sandy or gravelly floodplains, stream and lake margins, marshes, fens, coastal dunes, metamorphic or calcareous substrates
Elevation 0-3500 m (0-11500 ft) 0-800 m (0-2600 ft)
Distribution
from FNA
AK; AZ; CA; CO; ID; MT; NM; NV; OR; SD; UT; WA; WY; AB; BC; MB; NT; SK; YT; Mexico (Chihuahua, Sonora)
[WildflowerSearch map]
[BONAP county map]
from FNA
ME; MI; MN; NH; VT; WI; MB; NB; NL; NS; ON; QC; SK; SPM
[WildflowerSearch map]
[BONAP county map]
Discussion

Western Salix scouleriana and eastern S. humilis are closely related and are sometimes difficult to separate. Although there is an apparent range disjunction between them in western Manitoba, it may be a collecting gap. In general, S. scouleriana differs from S. humilis in being a taller shrub, sometimes even tree-like, with broader leaves and longer catkins, floral bracts, stigmas, and styles, but these quantitative characteristics all overlap. The apparent difference in anther length (S. scouleriana 0.7–1.2 mm; S. humilis 0.4–0.6 mm) may be correlated with a difference in chromosome number. Salix scouleriana is tetraploid (Y. Suda and G. W. Argus 1968); S. humilis has been reported to be both diploid (Suda and Argus; L. Zsuffa and Y. Raj, unpubl.) and tetraploid (R. D. Dorn 1976). The latter count was from the same population as the one by Suda and Argus. Further chromosome counts are indicated.

See 77. Salix hookeriana for comparative descriptions.

Hybrids:

Salix scouleriana forms natural hybrids with S. hookeriana, S. planifolia, and S. pulchra.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Salix pellita sometimes has foliaceous stipules on late leaves. When present, they are correlated with hairy rather than glabrous branchlets. There is no clear evidence of hybridity in such specimens but further study is indicated.

Vegetative specimens of Salix pellita can be difficult to separate from S. viminalis and S. ×smithiana in eastern Canada, where the latter were introduced for coarse basketry and have become naturalized. The introduced species usually are tall shrubs to small trees, with branches usually flexible at base and not strongly glaucous, and their leaves tend to be broader. In contrast, S. pellita is a mid shrub rarely to 6 m but never tree-like, its branches usually are highly brittle at the base and often strongly glaucous, and its leaves tend to be narrower.

See 85. Salix drummondiana for further comparative descriptions.

Hybrids:

Salix pellita forms natural hybrids with S. alaxensis var. alaxensis, S. discolor, S. pedicellaris, S. petiolaris, and S. planifolia.

Salix pellita × S. petiolaris: Leaves of this hybrid are distinctly serrate and flat, as in S. petiolaris, but branchlets are glaucous and bud gradation is caprea-type as in S. pellita. It is uncommon in eastern Saskatchewan.

Salix pellita × S. planifolia: This cross is suspected to occur in Labrador, Newfoundland, Quebec, and Ontario. Both parents are tetraploids and flower at the same time. The name S. pellita forma psila may apply to this hybrid.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 7, p. 131. FNA vol. 7, p. 136.
Parent taxa Salicaceae > Salix > subg. Vetrix > sect. Cinerella Salicaceae > Salix > subg. Vetrix > sect. Phylicifoliae
Sibling taxa
S. alaxensis, S. alba, S. amygdaloides, S. arbusculoides, S. arctica, S. arctophila, S. argyrocarpa, S. arizonica, S. athabascensis, S. atrocinerea, S. aurita, S. babylonica, S. ballii, S. barclayi, S. barrattiana, S. bebbiana, S. bonplandiana, S. boothii, S. brachycarpa, S. breweri, S. calcicola, S. candida, S. caprea, S. caroliniana, S. cascadensis, S. chamissonis, S. chlorolepis, S. cinerea, S. columbiana, S. commutata, S. cordata, S. daphnoides, S. delnortensis, S. discolor, S. drummondiana, S. eastwoodiae, S. elaeagnos, S. eriocephala, S. euxina, S. exigua, S. famelica, S. farriae, S. floridana, S. fuscescens, S. geyeriana, S. glauca, S. gooddingii, S. hastata, S. herbacea, S. hookeriana, S. humboldtiana, S. humilis, S. interior, S. irrorata, S. jejuna, S. jepsonii, S. laevigata, S. lasiandra, S. lasiolepis, S. lemmonii, S. ligulifolia, S. lucida, S. lutea, S. maccalliana, S. melanopsis, S. monochroma, S. monticola, S. myricoides, S. myrsinifolia, S. myrtillifolia, S. nigra, S. niphoclada, S. nivalis, S. nummularia, S. orestera, S. ovalifolia, S. pedicellaris, S. pellita, S. pentandra, S. petiolaris, S. petrophila, S. phlebophylla, S. planifolia, S. polaris, S. prolixa, S. pseudomonticola, S. pseudomyrsinites, S. pulchra, S. purpurea, S. pyrifolia, S. raupii, S. reticulata, S. richardsonii, S. rotundifolia, S. sericea, S. serissima, S. sessilifolia, S. setchelliana, S. silicicola, S. sitchensis, S. sphenophylla, S. stolonifera, S. taxifolia, S. thurberi, S. tracyi, S. triandra, S. turnorii, S. tweedyi, S. tyrrellii, S. uva-ursi, S. vestita, S. viminalis, S. wolfii, S. ×fragilis, S. ×jesupii, S. ×pendulina, S. ×sepulcralis, S. ×smithiana
S. alaxensis, S. alba, S. amygdaloides, S. arbusculoides, S. arctica, S. arctophila, S. argyrocarpa, S. arizonica, S. athabascensis, S. atrocinerea, S. aurita, S. babylonica, S. ballii, S. barclayi, S. barrattiana, S. bebbiana, S. bonplandiana, S. boothii, S. brachycarpa, S. breweri, S. calcicola, S. candida, S. caprea, S. caroliniana, S. cascadensis, S. chamissonis, S. chlorolepis, S. cinerea, S. columbiana, S. commutata, S. cordata, S. daphnoides, S. delnortensis, S. discolor, S. drummondiana, S. eastwoodiae, S. elaeagnos, S. eriocephala, S. euxina, S. exigua, S. famelica, S. farriae, S. floridana, S. fuscescens, S. geyeriana, S. glauca, S. gooddingii, S. hastata, S. herbacea, S. hookeriana, S. humboldtiana, S. humilis, S. interior, S. irrorata, S. jejuna, S. jepsonii, S. laevigata, S. lasiandra, S. lasiolepis, S. lemmonii, S. ligulifolia, S. lucida, S. lutea, S. maccalliana, S. melanopsis, S. monochroma, S. monticola, S. myricoides, S. myrsinifolia, S. myrtillifolia, S. nigra, S. niphoclada, S. nivalis, S. nummularia, S. orestera, S. ovalifolia, S. pedicellaris, S. pentandra, S. petiolaris, S. petrophila, S. phlebophylla, S. planifolia, S. polaris, S. prolixa, S. pseudomonticola, S. pseudomyrsinites, S. pulchra, S. purpurea, S. pyrifolia, S. raupii, S. reticulata, S. richardsonii, S. rotundifolia, S. scouleriana, S. sericea, S. serissima, S. sessilifolia, S. setchelliana, S. silicicola, S. sitchensis, S. sphenophylla, S. stolonifera, S. taxifolia, S. thurberi, S. tracyi, S. triandra, S. turnorii, S. tweedyi, S. tyrrellii, S. uva-ursi, S. vestita, S. viminalis, S. wolfii, S. ×fragilis, S. ×jesupii, S. ×pendulina, S. ×sepulcralis, S. ×smithiana
Synonyms S. scouleriana var. poikila S. chlorophylla
Name authority Barratt ex Hooker: Fl. Bor.-Amer. 2: 145. (1838) (Andersson) Bebb: Bot. Gaz. 16: 106. (1891)
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