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

Mackenzie willow, Mackenzie's 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. Shrubs, 1–5 m. Stems: branches gray-brown or red-brown, not or weakly glaucous, (with sparkling wax crystals), glabrous or moderately villous; branchlets yellow-green, or yellow-brown to red-brown, glabrous or sparsely to moderately densely velvety, (inner membranaceous bud-scale layer free, separating from outer layer).
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 foliaceous, apex acuminate to rounded;

petiole convex to flat adaxially, 6–12 mm, glabrous or pilose adaxially;

largest medial blade narrowly oblong, narrowly elliptic, lanceolate, or obovate, 50–150 × 10–53 mm, 2.4–4.5 times as long as wide, base cordate, subcordate, rounded, or convex, margins flat, serrate, serrulate, or spinulose-serrulate, apex acuminate to acute, abaxial surface glaucous, glabrous, adaxial dull, glabrous, pilose, or sparsely pubescent, (sometimes adaxial stomata only along veins or apically);

proximal blade margins entire;

juvenile blade reddish or yellowish green, glabrous, pilose or sparsely long-silky abaxially, hairs white.

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.

adaxial nectary oblong to narrowly oblong, 0.8–1 mm;

filaments distinct or connate less than 1/2 their lengths, glabrous;

anthers purple turning yellow, (ellipsoid), 0.5–0.6 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.

adaxial nectary oblong, square, or flask-shaped, 0.3–0.8 mm, shorter than stipe;

stipe 1.3–4.2 mm;

ovary pyriform, glabrous, beak sometimes slightly bulged below styles;

ovules 12–22 per ovary;

styles 0.3–0.7 mm;

stigmas flat, abaxially non-papillate with rounded tip, or 2 plump lobes, or slenderly cylindrical, 0.16–0.28–0.4 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.

flowering as leaves emerge; staminate slender or stout, 16–41 × 8–12 mm, flowering branchlet 0.5–3 mm; pistillate moderately densely to loosely flowered, slender or stout, 19–66 × 8–18 mm, flowering branchlet 0.5–6 mm;

floral bract brown, 0.8–1.6 mm, apex acute or rounded, abaxially hairy mainly proximally, hairs straight or wavy.

2n

= 76.

Salix cinerea

Salix prolixa

Phenology Flowering mid Mar-late May. Flowering late Mar-late Jun.
Habitat Stream shores, mesic woodlands, gravelly or sandy beaches, waste ground Along streams, lakes, springs, marsh margins, sandy-gravel, sandy or silty substrates
Elevation 0-700 m (0-2300 ft) 100-2300 m (300-7500 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; CA; ID; MT; NV; OR; WA; WY; AB; BC; NT; YT
[WildflowerSearch map]
[BONAP county map]
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.)

Source FNA vol. 7, p. 132. FNA vol. 7, p. 125.
Parent taxa Salicaceae > Salix > subg. Vetrix > sect. Cinerella Salicaceae > Salix > subg. Vetrix > sect. Cordatae
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. 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. 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. cordata var. mackenzieana, S. eriocephala subsp. mackenzieana, S. mackenzieana, S. mackenzieana var. macrogemma, S. rigida var. mackenzieana, S. rigida var. macrogemma
Name authority Linnaeus: Sp. Pl. 2: 1021. (1753) Andersson: Monogr. Salicum, 94, plate 5, fig. 52. (1867)
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