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gray willow, large gray or gray willow, large gray willow

barren-ground willow, snow willow

Habit Shrubs, 3–7 m. Stems: branches brownish, not glaucous, pilose, villous, or tomentose to glabrescent, (peeled wood with striae to 62 mm); branchlets yellow-brown, pilose, velvety, or densely villous. Plants 0.3–1.5(–3) m, not clonal.
Stems

erect, decumbent, or trailing;

branches gray-brown, yellow-brown, or red-brown, pilose, villous, or long-silky to glabrescent;

branchlets violet, red-brown, or yellow-brown, pilose, densely villous, long-silky, or tomentose.

Leaves

stipules rudimentary or foliaceous on early ones, foliaceous on late ones, apex acute or rounded;

petiole convex to flat adaxially, 4–15 mm, tomentose adaxially;

largest medial blade elliptic, broadly elliptic, oblanceolate, or obovate, 65–105 × 22–52 mm, 2–3 times as long as wide, base convex or cuneate, margins slightly revolute, entire, crenate, or sinuate, (glands submarginal), apex acuminate or convex, abaxial surface glaucous, tomentose, hairs erect or spreading, curly, adaxial dull or slightly glossy, pubescent or tomentose;

proximal blade margins entire;

juvenile blade yellowish green, sparsely to densely tomentose abaxially, hairs white.

stipules (sometimes marcescent), foliaceous, (sometimes obscured by hairs);

petiole (shallowly grooved adaxially), 2–5.5 mm, (usually shorter than or barely exceeding subtended bud, villous adaxially);

largest medial blade hypostomatous or amphistomatous, narrowly oblong, narrowly to broadly elliptic, lanceolate, or obovate, 13–64 × 6–22 mm, 1.6–5.5 times as long as wide, base convex, margins slightly revolute, entire (obscured by hairs), apex acuminate or acute, abaxial surface densely villous or woolly to pilose, hairs straight or wavy, adaxial slightly glossy, moderately densely to sparsely villous;

proximal blade margins entire;

juvenile blade abaxially densely long-silky.

Staminate flowers

adaxial nectary oblong or ovate, 0.5–1 mm;

filaments distinct, glabrous or hairy basally;

anthers yellow or purple turning yellow, ellipsoid or shortly cylindrical, 0.7–1 mm.

abaxial nectary 0.5–1.2 mm, adaxial nectary narrowly oblong to ovate or flask-shaped, 0.5–1.5 mm, nectaries distinct or connate and cup-shaped;

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

anthers ellipsoid or globose, 0.3–0.5 mm.

Pistillate flowers

adaxial nectary oblong or square, 0.4–1 mm, shorter than stipe;

stipe 1.2–2.7 mm;

ovary pyriform, long-silky, beak slightly bulged below styles;

ovules 12 per ovary;

styles 0.2–0.5 mm;

stigmas slenderly or broadly cylindrical, 0.3–0.6 mm.

abaxial nectary rarely present, 0.7 mm, adaxial nectary narrowly oblong, ovoid, or flask-shaped, 0.5–2 mm, longer than stipe;

stipe 0–0.5 mm;

ovary pyriform, very densely villous or long-silky, beak slightly bulged below or abruptly tapering to styles;

ovules 8–20 per ovary;

styles connate to almost distinct, 0.2–0.8 mm;

stigmas slenderly to broadly cylindrical, 0.2–0.36–0.6 mm.

Capsules

5–5.6 mm.

4–6 mm.

Catkins

flowering before leaves emerge; staminate stout or subglobose, 26–39 × 12–26 mm, flowering branchlet 0–5 mm; pistillate densely flowered, stout or subglobose, 27–54(–75 in fruit) × 4–15 mm, flowering branchlet 1–5(–10) mm;

floral bract dark brown, black, or bicolor, 2–3 mm, apex acute or convex, abaxially hairy, hairs straight.

staminate 12–42 × 4–14 mm, flowering branchlet 0–20 mm; pistillate densely flowered, slender, stout, or subglobose, 16–69 × 4–13 mm, flowering branchlet 4–30 mm;

floral bract tawny, brown, or black, 1.2–3.2 mm, apex rounded, entire, abaxially sparsely to moderately densely hairy, hairs wavy.

2n

= 76.

Salix cinerea

Salix niphoclada

Phenology Flowering mid Mar-late May. Flowering Jun–Jul.
Habitat Stream shores, mesic woodlands, gravelly or sandy beaches, waste ground Wet to moderately well-drained calcareous, gravelly or sandy floodplains, terraces, eskers, drumlins, fine, silty loess deposits, dry to mesic stony alpine slopes and saline flats, limestone talus, sand blowouts, plains
Elevation 0-700 m (0-2300 ft) 10-2300 m (0-7500 ft)
Distribution
from FNA
AL; CT; DC; GA; IA; KY; LA; MA; MD; MI; MO; NC; NJ; NY; OH; PA; RI; SC; SD; TN; UT; VA; WI; WV; ON; Eurasia [Introduced in North America]
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; BC; NT; NU; YT; Asia (Russia)
Discussion

The Ohio occurrence of Salix cinerea is based on information from T. Cooperrider (pers. comm.).

Salix cinerea and S. atrocinerea are very closely related. Their occurrence in the flora area, as naturalized introductions, is not well understood, probably because they usually are introduced under the name S. caprea, and that species often is not treated in North American floristic literature (e.g., C. K. Schneider 1921; M. L. Fernald 1950). They probably are introductions of long-standing brought to the New World for their value as ornamentals and bee-plants. Salix atrocinerea was first documented in the southeastern United States (G. W. Argus 1986) after plants with ferruginous hairs and prominently striate wood were found in North Carolina; since that time, it has been found in other states and provinces. In the northeastern states, S. atrocinerea and S. cinerea are thought to be invasive species. The species do reproduce by seed and hundreds of seedlings were observed in a drained reservoir (A. Zinovjev, pers. comm.) and on sandy pond shores (T. Rawinski, pers. comm.), where they are thought to compete with native species.

The presence of long, prominent, striae on the peeled wood of 4–5 year old branches is commonly used in European literature (K. H. Rechinger 1993; A. K. Skvortsov 1999) to separate Salix cinerea and S. atrocinerea from S. caprea etc., in which the wood is smooth or with fewer, shorter striae. In the flora area, long striae also occur in S. bebbiana, S. discolor, and S. humilis, but usually they are not as long as or as prominent in S. cinerea and S. atrocinerea. Some floras (e.g., F. Martini and P. Paiero 1988) use the relative prominence of striae to separate S. cinerea and S. atrocinerea, but their separation remains difficult. The presence of ferruginous hairs on the leaves of S. atrocinerea is the best diagnostic characteristic, but they are not always present or easily observed. For a comparison of these species, see the key to species under subg. Vetrix. For further discussion of morphologies, see Salix ×smithiana Willdenow [p. 132] and 76. S. discolor.

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

Salix niphoclada was treated as S. brachycarpa subsp. niphoclada (G. W. Argus 1965, 1973) because where the ranges of the two taxa overlap in northern British Columbia they appeared to intergrade. Species rank is used here, however, because there is no evidence to suggest that intergradation is common or extends beyond the small area of overlap.

Salix brachycarpa var. fullertonensis, which mainly occurs in southern Nunavut and the western side of Hudson Bay, is characterized by smaller leaves and catkins, broad, reddish floral bracts, and more sparsely hairy branchlets (G. W. Argus 1965). Its intergradation with S. niphoclada is so extensive that it is not recognized here as a separate taxon.

Hybrids:

Salix niphoclada forms natural hybrids with S. glauca var. acutifolia and S. setchelliana.

Salix niphoclada × S. setchelliana is a putative hybrid from Sheep Mountain, Kluane, Yukon, at 1180 m. It resembles S. niphoclada in leaf shape and indumentum, stigmas 0.6 mm, floral bracts oblong, 1.8 mm, and in the shape and length of pistillate catkins, but it has the glabrous, reddish ovaries of S. setchelliana. Both putative parents occur in the area.

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

Source FNA vol. 7, p. 132. FNA vol. 7, p. 88.
Parent taxa Salicaceae > Salix > subg. Vetrix > sect. Cinerella Salicaceae > Salix > subg. Chamaetia > sect. Glaucae
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. 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
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. 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. brachycarpa subsp. fullertonensis, S. brachycarpa var. fullertonensis, S. brachycarpa var. mexiae, S. brachycarpa subsp. niphoclada, S. fullertonensis, S. glauca var. niphoclada, S. muriei, S. niphoclada var. fullertonensis, S. niphoclada var. mexiae, S. niphoclada var. muriei
Name authority Linnaeus: Sp. Pl. 2: 1021. (1753) Rydberg: Bull. New York Bot. Gard. 1: 272. (1899)
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