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mountain willow, Scouler willow, Scouler's willow

Geyer willow, Geyer'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. Plants 0.6–5 m, (sometimes forming clones by stem fragmentation).
Stems

branches (sometimes ± brittle at base), yellow-green, gray-brown, red-brown, or violet, usually glaucous, glabrous or sparsely tomentose;

branchlets yellowish, yellow-brown, red-brown, or violet, (strongly glaucous or not), glabrous or sparsely to moderately densely pubescent, (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 usually absent or rudimentary (rarely foliaceous);

petiole convex to flat, or shallowly to deeply grooved adaxially, 2–9 mm, velvety, short-silky, or pubescent adaxially;

largest medial blade lorate, narrowly elliptic, or linear, 32–89 × 5.5–14 mm, 3.6–8.4(–11.3) times as long as wide, base cuneate or convex, margins flat or slightly revolute, entire or distantly and shallowly serrulate, apex acute to acuminate, abaxial surface glaucous, glabrous or densely short- or long-silky, hairs (white, sometimes also ferruginous), straight, adaxial slightly glossy, densely short- or long-silky, especially midrib, to glabrescent, (hairs white, sometimes also ferruginous);

proximal blade margins entire or distantly and shallowly serrulate;

juvenile blade reddish or yellowish green, densely to sparsely long- or short-silky 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, ovate, or square, 0.3–0.8(–0.9) mm;

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

anthers yellow or purple turning yellow, ellipsoid or globose, 0.4–0.5(–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, square, or ovate, 0.2–1 mm;

stipe (0.4–)1–2.8 mm;

ovary pyriform (gourd-shaped), beak gradually tapering to styles;

ovules 6–12 per ovary;

styles 0.1–0.2(–0.6) mm;

stigmas flat, abaxially non-papillate with rounded or pointed tip, 0.2–0.3–0.44 mm.

Capsules

4.5–11 mm.

(3–)4–6 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 or) as leaves emerge; staminate globose, (1–1.1–)11–18 × 6–11 mm, flowering branchlet 1–5 mm; pistillate densely to loosely flowered, subglobose to globose, 8–21 × 7–17 mm, flowering branchlet 0.5–8 mm;

floral bract tawny or brown (black), 1.2–2.8 mm, apex rounded or acute, abaxially hairy, hairs short, wavy or straight.

2n

= 76.

= 38.

Salix scouleriana

Salix geyeriana

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 Lowland wet streamsides, lakeshores, sedge meadows, springs, seepages, swamps, cienegas, fine-textured substrates
Elevation 0-3500 m (0-11500 ft) 10-3300 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
AZ; CA; CO; ID; MT; NM; NV; OR; UT; WA; WY; BC
[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 geyeriana is characterized by its dark gray appearance, slender, dark branches, narrow leaves long-silky on both surfaces, general absence of stipules, and small, subglobose catkins. Plants in the Pacific Northwest with foliaceous stipules may be hybrids or introgressants, but the other parent is unknown.

Hybrids:

Salix geyeriana forms natural hybrids with S. bebbiana, S. irrorata, S. lemmonii, S. ligulifolia, and S. pedicellaris. Alleged hybrids with S. sitchensis, based on plants from British Columbia with broader, more hairy leaves, and catkins longer than in S. geyeriana, but with the short stipes of S. sitchensis (J. K. Henry 1915), are unconvincing.

Salix geyeriana × S. irrorata: A series of specimens from Arizona usually resemble S. geyeriana but have some characters of S. irrorata: foliaceous stipules, toothed leaf margins, catkins flowering before leaves emerge, shorter stipes (0.4–1.2 mm), and longer styles (0.2–0.6 mm). They also have some unique characters: proximal leaves sometimes serrulate, leaves sometimes amphistomatous, adaxial leaf surfaces mostly with ferruginous hairs, and ovaries sometimes gourd-shaped.

Salix geyeriana × S. lemmonii is uncommon but in mixed stands of the parental species some plants resemble S. geyeriana in having relatively short, subspherical catkins, small anthers, and petioles sometimes with petiolar glands; and S. lemmonii in having leaf blades amphistomatous, margins serrulate, and foliaceous stipules on early leaves. Because the species have different chromosome numbers, hybrids may be infertile, but occasional seeds have been seen. This hybrid is known from California (Lassen and Sierra counties), Oregon (Jefferson and Lane counties), and near Victoria, British Columbia.

Salix geyeriana × S. ligulifolia: Plants in Arizona with rudimentary stipules and leaves with ferruginous hairs may be this hybrid.

Salix geyeriana × S. pedicellaris occurs in Washington. It has the white and ferruginous hairs on leaves and ovaries of S. geyeriana, and leaves glaucous adaxially with prominent 2 and 3 veins of S. pedicellaris.

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

Source FNA vol. 7, p. 131. FNA vol. 7, p. 153.
Parent taxa Salicaceae > Salix > subg. Vetrix > sect. Cinerella Salicaceae > Salix > subg. Vetrix > sect. Geyerianae
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. 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. geyeriana var. argentea, S. geyeriana var. meleina
Name authority Barratt ex Hooker: Fl. Bor.-Amer. 2: 145. (1838) Andersson: Öfvers. Kongl. Vetensk.-Akad. Förh. 15: 122. (1858)
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