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mountain willow, Scouler willow, Scouler's willow

Barratt's 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, 0.3–1.5 m. Stems: branches red-brown, not or weakly glaucous, glabrous or villous in patches; branchlets red-brown or violet, moderately densely and coarsely villous, (bud-scale oily).
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 (sometimes marcescent), foliaceous, (resinous, 1.5–7.5 mm), apex acute;

petiole shallowly grooved, or convex to flat adaxially, 4–15 mm, villous or puberulent adaxially, (weakly ventricose around floral buds);

largest medial blade narrowly to broadly elliptic, oblanceolate, or obovate, 35–95 × 10–29 mm, 2.2–4.2(–5) times as long as wide, base usually convex, rounded, or cuneate, sometimes cordate, margins flat, entire, apex acute, convex, or acuminate, abaxial surface not glaucous, moderately to very densely long-silky tomentose to glabrescent, hairs wavy, adaxial slightly glossy, sparsely villous or pubescent to glabrescent;

proximal blade margins entire;

juvenile blade color sometimes obscured by hairs, very densely 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 narrowly oblong to oblong, 0.4–1.8 mm;

filaments distinct;

anthers yellow or purple turning yellow, ellipsoid or shortly cylindrical, 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 narrowly oblong to oblong, 0.6–1.3 mm;

stipe 0.2–0.6 mm;

ovary pyriform, (hairs refractive), beak gradually tapering to styles;

ovules 16–21 per ovary;

styles 0.6–1.8 mm;

stigmas 0.28–0.47–0.64 mm.

Capsules

4.5–11 mm.

4.5–6 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 or subglobose, 20–57 × 13–18 mm, flowering branchlet 0–2 mm; pistillate densely flowered, slender to stout, 28–92(–105 in fruit) × 12–19 mm, flowering branchlet 0–5 mm;

floral bract brown or black, 2.8–5.2 mm, apex acute to convex, abaxially hairy, hairs straight.

2n

= 76.

Salix scouleriana

Salix barrattiana

Phenology Flowering late Feb-mid Jun. Flowering late May-late 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 Moist to wet gravel bars, fans and terraces, stream banks, shrub fens, thickets and meadows, wet alpine tundra, often on limestone substrates
Elevation 0-3500 m (0-11500 ft) 150-3200 m (500-10500 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; MT; WY; AB; BC; NT; YT
[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 barrattiana has stipules and buds that are typically strongly oily or resinous, staining pressing sheets yellow. The Montana and Wyoming records are the basis for a conservation assessment by J. A. R. Ladyman (www.fs.fed.us/r2/projects/scp/assessments/salixbarrattiana.pdf). The Wyoming population is represented by three staminate specimens. Their buds and stipules are not conspicuously oily and further verification is needed.

Salix barrattiana is placed here in sect. Villosae, but it is morphologically similar also to members of sect. Lanatae. The most conspicuous difference is its hairy ovaries. Inconsistent phenetic clustering of this species (G. W. Argus 1997) shows the difficulty in determining its sectional placement. The suggestion that it may link the two sections by hybridization and introgression, or by alloploidy, still remains to be assessed.

Hybrids:

Salix barrattiana forms natural hybrids with S. barclayi, S. commutata, and S. pseudomyrsinites.

Salix barrattiana × S. commutata: This hybrid, known from Alberta and the Yukon, usually resembles S. barrattiana, but ovaries are hairy in patches, stipes at ca. 1 mm are long for that species, and buds and stipules are not oily. A British Columbia specimen has glabrous ovaries and oily stipules.

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

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

Source FNA vol. 7, p. 131. FNA vol. 7, p. 148.
Parent taxa Salicaceae > Salix > subg. Vetrix > sect. Cinerella Salicaceae > Salix > subg. Vetrix > sect. Villosae
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. 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. 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. barrattiana var. marcescens
Name authority Barratt ex Hooker: Fl. Bor.-Amer. 2: 145. (1838) Hooker: Fl. Bor.-Amer. 2: 146, plate 181. (1838)
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