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mountain willow, Scouler willow, Scouler's willow

firmleaf willow, tall blueberry 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. Plants 1–7 m. Stems: branches gray-brown, red-brown, or yellow-brown, glaucous to strongly so (slightly to highly glossy), villous to glabrescent; branchlets gray-brown, red-brown, yellow-brown, or yellow-green, (not or weakly glaucous), pilose, densely villous, or tomentose.
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 foliaceous on early ones, foliaceous on late ones, (0.6–8 mm), apex acute or obtuse;

petiole shallowly to deeply grooved adaxially, 2.5–8 mm, glabrous or villous adaxially;

largest medial blade (sometimes amphistomatous), narrowly to broadly elliptic, oblong to oblanceolate or obovate, 32–109 × 10–47 mm, 1.8–4.8 times as long as wide, base convex, cuneate, or subcordate, sometimes cordate, margins flat, entire, crenate, or serrulate, apex acute, convex, or acuminate, abaxial surface not glaucous, glabrous or pilose, hairs (white, sometimes also ferruginous), wavy, adaxial slightly glossy, glabrous, pilose, pubescent, moderately densely short-silky, or velvety, midrib remaining pilose or short-hairy, (hairs sometimes also ferruginous, straight and geniculate);

proximal blade margins serrulate or entire;

juvenile blade sometimes reddish or yellowish green, abaxially glabrous, or midrib sparsely pubescent, or densely villous or short-silky, 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 square, 0.2–0.4–0.6 mm;

filaments distinct, glabrous;

anthers purple turning yellow, 0.4–0.7 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 square or oblong, 0.2–0.4 mm, shorter than stipe;

stipe 0.8–1.4 mm;

ovary pyriform, glabrous, beak slightly bulged below styles;

ovules 11–18 per ovary;

styles 0.4–1.6 mm;

stigmas flat, abaxially non-papillate with rounded tip, or 2 plump lobes, 0.16–0.24–0.32 mm.

Capsules

4.5–11 mm.

4.4–6.4 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 as leaves emerge; staminate stout, 16.5–35.5 × 7–15 mm, flowering branchlet 0.5–12 mm; pistillate moderately or densely flowered, slender or stout, 10.5–68 × 5–20 mm, flowering branchlet 0.5–10 mm;

floral bract brown, black, tawny, or bicolor, 0.6–1.1 mm, apex retuse, abaxially hairy, hairs long-wavy or curly.

2n

= 76.

= 76.

Salix scouleriana

Salix pseudomyrsinites

Phenology Flowering late Feb-mid Jun. Flowering early May-early Jul.
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 Shores of lakes and streams, dwarf-birch thickets, fens, marl bogs, rarely in treed bogs
Elevation 0-3500 m (0-11500 ft) 40-1000 m (100-3300 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; AB; BC; MB; NT; NU; ON; SK; YT
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 pseudomyrsinites occurs in Nunavut on Akimiski Island in James Bay.

Salix pseudomyrsinites and S. myrtillifolia, although sometimes treated as conspecific (R. D. Dorn 1975), deserve species rank. They differ in chromosome number and are distinct in habit, habitat, and general appearance, including glossiness of leaves, as well as a number of technical characteristics (L. A. Viereck and E. L. Little Jr. 1972; G. W. Argus 1973, 1997). There is no field evidence of hybridization, but some herbarium specimens appear to be intermediates, having the habit or habitat of one species and the leaf hairiness of the other.

Salix myrtillifolia is distinguished from S. pseudomyrsinites by having shrubs low, decumbent, 0.1–0.6 m, rarely to 1 m, of treed bogs and fens, juvenile and mature leaves typically glabrous, stipules usually rudimentary, 0.2–1.8(–5) mm, and styles often shorter, 0.3–0.7 mm; S. pseudomyrsinites has shrubs tall, erect, 1–7 m, of riparian habitats, juvenile leaves pubescent with hairs persisting on mature leaves, at least on adaxial midrib, stipules usually prominent and foliaceous, 0.6–8 mm, and styles often longer, 0.4–1.6 mm.

The nomenclature of these species is confusing. When treating them as varieties E. Hultén (1968) used the name Salix myrtillifolia var. pseudomyrsinites and R. D. Dorn (1975) used the name S. myrtillifolia var. cordata. At the species level, the name S. novae-angliae was used (L. A. Viereck and E. L. Little Jr. 1972; G. W. Argus 1973), but that name is illegitimate (Dorn) and is replaced by S. pseudomyrsinites (Argus 1997).

Hybrids:

Salix pseudomyrsinites forms natural hybrids with S. barrattiana.

Salix pseudomyrsinites × S. barrattiana is a rare hybrid that combines the characters of the two parents.

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

Source FNA vol. 7, p. 131. FNA vol. 7, p. 110.
Parent taxa Salicaceae > Salix > subg. Vetrix > sect. Cinerella Salicaceae > Salix > subg. Vetrix > sect. Hastatae
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. pellita, S. pentandra, S. petiolaris, S. petrophila, S. phlebophylla, S. planifolia, S. polaris, S. prolixa, S. pseudomonticola, 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. myrtillifolia var. cordata, S. myrtillifolia var. pseudomyrsinites, S. novae-angliae var. cordata
Name authority Barratt ex Hooker: Fl. Bor.-Amer. 2: 145. (1838) Andersson: Öfvers. Kongl. Vetensk.-Akad. Förh. 15: 129. (1858)
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