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black willow

large gray willow, rusty willow

Habit Trees, 5–20+ m. Stems: branches highly brittle at base, red-brown to yellow-brown, glabrous; branchlets gray-brown to red-brown, glabrous or pilose to villous. Shrubs, 3–12 m. Stems: branches yellow-brown, gray-brown, or red-brown, not glaucous, pilose or villous to glabrescent, (peeled wood often with many striae, to 45 mm); branchlets gray-brown or yellow-brown, puberulent, pilose, villous, or velvety.
Leaves

stipules rudimentary or foliaceous on early ones, usually foliaceous on late ones, (glands few or absent adaxially), apex acuminate, acute, or rounded;

petiole (margins covering groove, with spherical glands distally), (2–)3–10(–15) mm, glabrous or pilose adaxially;

largest medial blade (sometimes amphistomatous), very narrowly elliptic, lanceolate to narrowly lanceolate, or linear to lorate, (50–)70–103(–190) × (6–)7.5–17(–23) mm, 6–13 times as long as wide, base cuneate to convex, margins serrulate, apex acuminate, acute, or caudate, abaxial surface (not glaucous), glabrous or pilose, hairs white or ferruginous, wavy, adaxial slightly glossy, glabrous or pilose (especially on midribs);

proximal blade margins serrulate;

juvenile blade glabrous or pilose abaxially, hairs white and/or ferruginous.

stipules (sometimes marcescent) foliaceous, apex acute;

petiole convex to flat adaxially, 3–15 mm, tomentose, or velvety to glabrescent adaxially;

largest medial blade narrowly to broadly elliptic, oblanceolate, obovate, broadly obovate, 29–105 × 14–52 mm, 1.8–4.3 times as long as wide, base cuneate or convex, margins slightly revolute, entire, crenate, or sinuate, (glands submarginal or epilaminal), apex acute, convex, or acuminate, abaxial surface glaucous, tomentose or coarsely villous to glabrescent, hairs (white, sometimes also ferruginous), erect, spreading, or appressed, wavy or curved, adaxial dull or slightly glossy, pubescent or pilose, (hairs white, sometimes also ferruginous);

proximal blade margins entire;

juvenile blade yellowish green or reddish, glabrous, tomentose, or long-silky abaxially, hairs white, sometimes also ferruginous.

Staminate flowers

abaxial nectary 0.3–1 mm, adaxial nectary oblong to ovate, 0.2–0.6 mm, nectaries distinct or connate and shallowly cup-shaped;

stamens 4–6;

filaments hairy on proximal 1/2 or basally;

anthers 0.4–0.6 mm, (axes strongly recurved).

adaxial nectary narrowly oblong, oblong, or ovate, 0.4–0.9 mm;

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

anthers yellow, shortly cylindrical or ovoid, 0.6–1 mm.

Pistillate flowers

adaxial nectary oblong, (swollen), 0.2–0.5 mm;

stipe 0.5–1.5 mm;

ovary pyriform to obclavate, (rarely pilose), beak slightly bulged below styles;

ovules 12–16 per ovary;

styles 0.1–0.3 mm;

stigmas (sometimes 2 plump lobes), 0.2–0.28–0.36 mm.

adaxial nectary oblong, square, or obovate, 0.4–0.9 mm, shorter than stipe;

stipe 1.2–2.7 mm;

ovary pyriform or obclavate, tomentose or short-silky, beak slightly bulged below styles;

ovules 12 per ovary;

styles 0.2–0.5 mm;

stigmas broadly cylindrical, 0.23–0.43–0.63 mm.

Capsules

3–5 mm.

5–7 mm.

Catkins

staminate 35–83 × 7–13 mm, flowering branchlet 5–35 mm; pistillate 23–74(–80 in fruit) × 5–10 mm, flowering branchlet 6–35 mm;

floral bract 1–3 mm, apex acute or rounded, entire, abaxially sparsely hairy, hairs wavy; pistillate bract deciduous after flowering.

flowering before leaves emerge; staminate stout, 11–16 mm, flowering branchlet 0–5 mm; pistillate densely to loosely flowered, stout, 11–18 mm, flowering branchlet 0–3 mm;

floral bract brown, black, or bicolor, 1–3 mm, apex acute, convex, or rounded, abaxially hairy, hairs straight or wavy.

2n

= 38.

= 76.

Salix nigra

Salix atrocinerea

Phenology Flowering (south) early Feb-early May, (north) late Mar-early Jul. Flowering mid Mar-mid May.
Habitat Floodplains, edges of ponds and lakes, swamps, marshes, white cedar bogs, wet meadows, open fields, roadside ditches, mixed upland deciduous woods along streams Wooded wetlands, marshes, sandy beaches, mesic prairies, edges of birch-maple or oak woodlands
Elevation 10-1400 m (0-4600 ft) 0-700 m (0-2300 ft)
Distribution
from FNA
AL; AR; CT; DC; DE; FL; GA; IA; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; NC; NE; NH; NJ; NY; OH; OK; PA; RI; SC; TN; TX; VA; VT; WI; WV; NB; ON; QC; Mexico (Chihuahua)
[WildflowerSearch map]
[BONAP county map]
from FNA
CT; MA; ME; MO; NC; NE; NJ; NY; PA; RI; WI; ON; Europe [Introduced in North America]
[BONAP county map]
Discussion

Hybrids:

Salix nigra forms natural hybrids with S. alba, S. amygdaloides, S. caroliniana, S. gooddingii, and S. lucida.

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

Hairs on abaxial leaf surfaces of Salix atrocinerea often are spreading to erect, and curly as in S. humilis. Usually, S. atrocinerea can be recognized by its closely spaced parallel tertiary venation. See 76. S. discolor and 81. S. cinerea for further comparative descriptions.

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

Source FNA vol. 7, p. 36. FNA vol. 7, p. 133.
Parent taxa Salicaceae > Salix > subg. Protitea > sect. Humboldtianae Salicaceae > Salix > subg. Vetrix > sect. Cinerella
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. 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. 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. 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. nigra var. falcata, S. nigra var. lindheimeri S. cinerea var. atrocinerea, S. cinerea subsp. oleifolia
Name authority Marshall: Arbust. Amer., 139. (1785) Brotero: Fl. Lusit. 1: 31. (1804)
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