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mountain willow, Scouler willow, Scouler's willow

beak willow, Bebb willow, Bebb's willow, gray or Bebb's or long-beak willow, gray willow, grey willow, long-beak 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.
Stems

branches divaricate, sometimes ± brittle at base, yellow-brown to dark red-brown, not or weakly glaucous, pilose to glabrescent, peeled wood often with very dense striae, to 25 mm;

branchlets yellow-green or red-brown, moderately to very densely villous to glabrescent.

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 rudimentary or absent on early ones, apex acute, acuminate, or convex;

petiole convex to flat adaxially, 2–5.5–13 mm, pubescent adaxially;

largest medial blade narrowly oblong, narrowly elliptic, elliptic, oblanceolate, or obovate, 20–44–87 × 10–16–45 mm, base cuneate, convex, or rounded, margins flat, entire, crenate, or irregularly serrate, glands submarginal, apex acute, acuminate, or convex, abaxial surface glaucous, moderately densely pubescent or long-silky to glabrescent, hairs white or gray, wavy, adaxial finely impressed-reticulate, dull or slightly glossy, moderately densely pubescent, sparsely short-silky, or glabrescent, hairs white or gray;

proximal blade margins entire, gland-dotted;

juvenile blade yellowish green or reddish, pilose or sparsely to moderately densely tomentose or long-silky abaxially, hairs white.

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 ovate, 0.3–0.8 mm;

filaments distinct or connate less than 1/2 their lengths, glabrous or hairy on proximal 1/2;

anthers yellow or purple turning yellow, ellipsoid or shortly cylindrical, 0.5–0.8 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 or square, 0.3–0.8 mm;

ovary obclavate, beak slightly bulged below styles (long-beaked);

ovules 6–16 per ovary;

styles 0.1–0.4 mm;

stigmas slenderly to broadly cylindrical.

Capsules

4.5–11 mm.

5–9 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.

staminate flowering just before leaves emerge, pistillate flowering as leaves emerge; staminate stout to globose, 10–42 × 7–16 mm, flowering branchlet 0.5–11 mm; pistillate loosely flowered, stout, slender, or subglobose, 16.5–85 × 9–32 mm, flowering branchlet 1–26 mm;

floral bract tawny, 1.2–3.2 mm, apex rounded, abaxially hairy to glabrescent, hairs straight or wavy.

2n

= 76.

= 38.

Salix scouleriana

Salix bebbiana

Phenology Flowering late Feb-mid Jun. Flowering early 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 Riparian and upland conifer forests, wet lowland thickets, Picea mariana treed bogs, stream margins, lakeshores, prairie margins, dry south-facing slopes, cienegas, seeps, disturbed areas
Elevation 0-3500 m (0-11500 ft) 0-3300 m (0-10800 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
AK; AZ; CA; CO; CT; IA; ID; IL; IN; MA; MD; ME; MI; MN; MT; ND; NE; NH; NJ; NM; NV; NY; OH; OR; PA; RI; SD; UT; VT; WA; WI; WY; AB; BC; MB; NB; NL; NS; NT; NU; ON; PE; QC; SK; YT; Asia
[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 bebbiana occurs in Nunavut on Akimiski Island in James Bay.

Hybrids:

Salix bebbiana forms natural hybrids with S. candida, S. geyeriana, S. humilis, and S. petiolaris. Reports of hybrids with S. discolor (C. K. Schneider 1921; M. L. Fernald 1950) are not based on convincing specimens, and synthetic hybrids could not be made (G. W. Argus 1974). Reports of hybrids with S. eriocephala and S. myricoides (Fernald) are unverified. Controlled pollinations with S. eriocephala and S. interior had low seed viability (A. Mosseler 1990).

Salix bebbiana × S. candida (S. ×cryptodonta Fernald, as species) is intermediate between parental species. It resembles S. candida in having juvenile leaves densely woolly, mature leaves sparsely to moderately woolly abaxially, margins strongly revolute to crenulate, and ovaries woolly; and S. bebbiana in having stipes 2.8–3 mm and capsules long-beaked, 8–9 mm. The hybrid commonly occurs in Newfoundland.

Salix bebbiana × S. geyeriana: A plant with the pistillate catkins and flowers of S. bebbiana and the narrow, entire or slightly serrulate leaves with white and ferruginous hairs of S. geyeriana was collected by R. D. Dorn in a mixed population in Montana (Beaverhead County).

Salix bebbiana × S. humilis: Reported by C. K. Schneider (1921) and M. L. Fernald (1950) and successfully synthesized by G. W. Argus (1974, 1986).

Salix bebbiana × S. petiolaris is known from Ontario, based on an infertile pistillate specimen, and from Alberta and Saskatchewan, where it is relatively uncommon. It was successfully synthesized (G. W. Argus 1974, 1986) and controlled pollinations showed high seed viability (A. Mosseler 1990).

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

Source FNA vol. 7, p. 131. FNA vol. 7, p. 134.
Parent taxa Salicaceae > Salix > subg. Vetrix > sect. Cinerella Salicaceae > Salix > subg. Vetrix > sect. Fulvae
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. 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. 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. rostrata, S. bebbiana var. capreifolia, S. bebbiana var. depilis, S. bebbiana var. luxurians, S. bebbiana var. perrostrata, S. bebbiana var. projecta, S. depressa subsp. rostrata
Name authority Barratt ex Hooker: Fl. Bor.-Amer. 2: 145. (1838) Sargent: Gard. & Forest 8: 463. (1895)
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