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mountain willow, Scouler willow, Scouler's willow

Pacific willow (var. lasiandra), shining willow, whiplash willow (ssp. caudata)

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 or trees, 4–6 m. Stems: branches flexible to highly brittle at base, yellow-brown, gray-brown, or red-brown, slightly to highly glossy, glabrous or villous to glabrescent; branchlets yellow-brown, gray-brown, or red-brown, glabrous, pilose, densely villous, or velvety, hairs spreading, straight, wavy, or crinkled.
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 foliaceous, apex convex to rounded;

petiole shallowly to deeply grooved adaxially, 5–13 mm, with clusters of spherical or foliaceous glands distally, glabrous, pilose, or densely villous adaxially;

largest medial blade usually hypostomatous or hemiamphistomatous, rarely amphistomatous, lorate, very narrowly elliptic, narrowly elliptic, or lanceolate, (24–)55–133 × 11–43 mm, 2.5–6.2 times as long as wide, base convex or cuneate, margins flat, serrulate, apex acuminate to caudate, abaxial surface usually not glaucous (rarely so), glabrous, pilose, or moderately densely villous or long-silky, hairs appressed or spreading, white and/or ferruginous, straight or wavy, (coarse, caducous), adaxial (secondary veins flat or protruding), slightly or highly glossy, glabrous, pilose, or long-silky, hairs white and/or ferruginous;

proximal blade margins entire and glandular-dotted, or serrulate or crenulate;

juvenile blade reddish or yellowish green, glabrous or densely villous or long-silky abaxially, hairs white and 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.

abaxial nectary 0.5–1.1 mm, adaxial nectary square or ovate, 0.3–0.9 mm, nectaries connate and cup-shaped;

stamens 3–6;

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

anthers ellipsoid, shortly cylindrical, obovoid, or globose, 0.6–0.8 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 square or ovate, (swollen), 0.2–0.5 mm, shorter than stipe;

stipe 0.5–2 mm;

ovary pyriform, beak slightly bulged below or gradually tapering to styles;

ovules 18–24 per ovary;

styles connate or distinct 1/2 their lengths, 0.5–0.8 mm;

stigmas flat, abaxially non-papillate with rounded tip, broadly cylindrical, or 2 plump lobes, 0.24–0.31–0.42 mm.

Capsules

4.5–11 mm.

5–7 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 19–69 × 4–14 mm, flowering branchlet 5–23 mm; pistillate (fruiting in summer), moderately densely to loosely flowered, slender to stout, 23–56(–70 in fruit) × 8–12 mm, flowering branchlet 8–25 mm;

floral bract 1.5–3 mm, apex convex or rounded, entire or toothed, abaxially sparsely hairy throughout or proximally, hairs wavy.

2n

= 76.

= 76.

Salix scouleriana

Salix lucida

Phenology Flowering late Feb-mid Jun. Flowering early May-mid 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 Sandy or gravelly floodplains, lake margins, sedge meadows, vernal pools, alvars, open fens, marl bogs, treed bogs
Elevation 0-3500 m (0-11500 ft) 0-600 m (0-2000 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
CT; DE; IA; IL; IN; MA; MD; ME; MI; MN; ND; NH; NJ; NY; OH; PA; RI; SD; VA; VT; WI; WV; MB; NB; NL; NS; ON; PE; 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.)

The Virginia plants of Salix lucida are introduced (G. W. Argus 1986).

The Salix lucida complex is a group of three weakly delimited taxa, S. lasiandra var. caudata, S. lasiandra var. lasiandra, and S. lucida. The morphological characters used to separate them (leaves amphistomatous or hypostomatous and blades glaucous abaxially or not) are usually geographically correlated, but there are exceptions. G. W. Argus (1986b) proposed, based on principal components analysis of morphological data, to treat them as a single species consisting of three subspecies. The geographic overlap of the northeastern S. lucida and the western S. lasiandra is a relatively small area in central Saskatchewan. Evidence of intergradation was based on cultivation of a plant that, in the wild, had leaves that were not glaucous abaxially but were glaucous in cultivation. It seems best to treat them as two species, S. lucida and S. lasiandra, the latter with two varieties, var. lasiandra and var. caudata.

Hybrids:

Salix lucida forms natural hybrids with S. alba and S. nigra. Hybrids with S. serissima have been reported (M. L. Fernald 1950) but no convincing specimens have been seen. Attempts to hybridize S. lucida with members of subg. Protitea (S. amygdaloides), subg. Longifoliae (S. interior), and subg. Vetrix (S. discolor, S. eriocephala, and S. petiolaris) were unsuccessful (A. Mosseler 1990).

Salix lucida × S. nigra (S. ×schneideri B. Boivin) seems to be a rare intersubgeneric hybrid between tetraploid S. lucida and diploid S. nigra. It is known only from the type specimen, an infertile plant, growing with both parents. It resembles S. lucida in bud-scale margins connate, in petiolar glands stalked or foliaceous, and in leaf shape, and S. nigra in stipules rudimentary on proximal leaves and sometimes even on early leaves, stipule apex acute, pistillate catkins relatively long and slender, and styles relatively short.

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

Source FNA vol. 7, p. 131. FNA vol. 7, p. 46.
Parent taxa Salicaceae > Salix > subg. Vetrix > sect. Cinerella Salicaceae > Salix > subg. Salix > sect. Salicaster
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. 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 Pleiarina lucida, S. lucida var. angustifolia, S. lucida var. intonsa
Name authority Barratt ex Hooker: Fl. Bor.-Amer. 2: 145. (1838) Muhlenberg: Ges. Naturf. Freunde Berlin Neue Schriften 4: 239, plate 6, fig. 7. (1803)
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