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weeping willow

bog willow

Habit Plants 0.2–1.5 m, forming clones by layering.
Stems

branches yellow-brown to red-brown;

branchlets sparsely to moderately densely tomentose, especially at nodes.

erect, decumbent or trailing;

branches gray-brown, glabrous;

branchlets yellow-brown or red-yellow, glabrous or puberulent (hairs straight, minute, inner membranaceous bud-scale layer free, not separating from outer layer).

Leaves

stipules absent or rudimentary on early ones;

petiole convex to flat or shallowly to deeply grooved adaxially, 7–9 mm, tomentose abaxially;

largest medial blade lanceolate, narrowly oblong, or narrowly elliptic, 90–160 × 5–20 mm, 5.5–10.5 times as long as wide, base cuneate, margins flat, spinulose-serrulate or serrulate, apex acuminate, caudate, or acute, surfaces glabrous or sparsely short-silky, hairs straight, dull adaxially;

proximal blade margins entire;

juvenile blade reddish or yellowish green.

stipules absent or rudimentary;

petiole (deeply to shallowly grooved adaxially), 3–8 mm, (glabrous or puberulent);

largest medial blade narrowly oblong, oblong, narrowly to broadly elliptic, narrowly oblanceolate or oblanceolate, 19–53(–69) × 5–20 mm, 1.8–4.9 times as long as wide, base convex or rounded, margins flat or slightly revolute, entire, apex acute, convex, or rounded, abaxial surface glabrous, adaxial dull, glaucous, glabrous (rarely very sparsely short-silky, hairs usually white, sometimes also ferruginous);

proximal blade margins entire;

juvenile blade (reddish or yellowish green), glabrous, puberulent, or sparsely pubescent abaxially, (hairs usually white, sometimes also ferruginous).

Staminate flowers

abaxial nectary 0.2–0.6 mm, adaxial nectary oblong or ovate, 0.4–0.7 mm, nectaries distinct or connate and cup-shaped;

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

anthers (sometimes reddish turning yellow), ellipsoid or globose.

abaxial nectary absent, adaxial nectary oblong or narrowly oblong, 0.5–1.1 mm;

filaments distinct or connate less than 1/2 their lengths, glabrous, or hairy basally or on proximal 1/2;

anthers (yellow), ellipsoid, 0.4–0.6 mm.

Pistillate flowers

adaxial nectary oblong, square, ovate, or obovate, 0.4–0.8 mm;

ovary ovoid or obturbinate, beak (sometimes pilose proximally), slightly bulged below or abruptly tapering to styles;

ovules 2–4 per ovary;

styles distinct or connate 1/2 their lengths, 0.2–0.3 mm;

stigmas flat, abaxially non-papillate with rounded tip, or 2 plump lobes (almost capitate), 0.2–0.3 mm.

abaxial nectary absent, adaxial nectary oblong, 0.2–1.4 mm, shorter than stipe;

stipe 2.1–3.2 mm;

ovary obclavate, often glaucous, glabrous, beak abruptly tapering to styles;

ovules 4–6 per ovary;

styles connate or distinct 1/2 their lengths, 0.1–0.2 mm;

stigmas flat, abaxially non-papillate with rounded tip, or 2 plump lobes, 0.2–0.25–0.36 mm.

Capsules

2–2.7 mm.

4–8 mm.

Catkins

(flowering just before leaves emerge); staminate 13–35 mm, flowering branchlet 1–6 mm; pistillate densely flowered, stout or subglobose, 9–27 × 2.5–7 mm, flowering branchlet (0–)2–4 mm;

floral bract 1.1–1.8 mm, apex acute, rounded, or truncate, entire, abaxially sparsely hairy throughout or proximally, hairs wavy.

staminate 11–21 × 4–8 mm, flowering branchlet 3–12 mm; pistillate loosely flowered, stout or subglobose, 14–37 × 5–14 mm, flowering branchlet 7–25 mm;

floral bract tawny or light rose, 0.8–1.6 mm, apex rounded, entire, abaxially very sparsely hairy distally, hairs straight or wavy.

2n

= 76.

= 38, 57, 76.

Salix babylonica

Salix pedicellaris

Phenology Flowering spring. Flowering mid Apr-mid Jul.
Habitat Around settlements Sphagnum bogs, fens, black spruce treed bogs
Elevation ca. 50 m (ca. 200 ft) 0-1400 m (0-4600 ft)
Distribution
from FNA
AL; AR; CA; DC; DE; FL; GA; KY; LA; MD; NC; SC; TN; VA; Asia [Introduced in North America; introduced also in Mexico (Mexico City), South America]
[WildflowerSearch map]
[BONAP county map]
from FNA
CT; IA; ID; IL; IN; MA; ME; MI; MN; ND; NH; NJ; NY; OH; OR; PA; RI; VT; WA; WI; AB; BC; MB; NB; NL; NS; NU; ON; QC; SK; YT; SPM
[WildflowerSearch map]
[BONAP county map]
Discussion

Little is known about the origin of the strongly weeping cultivar of Salix babylonica. It was described by Linnaeus (1737[1738]) based on young garden specimens (W. J. Bean 1970–1988, vol. 4). It is thought to have originated in China, although it no longer occurs in the wild and its origin is uncertain. Selections are thought to have been transported to Europe along the trade route from China. In Tajikistan, there are three cultivated clones, one of which is staminate (A. K. Skvortsov 1999). Taxonomic treatments of S. babylonica are variable. Some botanists recognize a single species, including both pendulous and non-pendulous forms (Skvortsov), while others recognize four species: S. babylonica, with a weeping habit, S. capitata Y. L. Chou & Skvortsov, S. pseudolasiogyne H. Léveillé, and the commonly cultivated S. matsudana Koidzumi (Fang Z. F. et al. 1999), with an erect or spreading habit. Here, S. babylonica is treated in a narrow sense, including only weeping forms.

Salix babylonica is not cold tolerant and is not commonly grown in Europe (R. D. Meikle 1984) or in northern North America. In the flora area, cultivated trees with strongly pendulous branches and branchlets have been identified as S. babylonica (G. W. Argus 1985, 1986, 1993), but many are hybrids with S. alba (S. ×sepulcralis) or S. euxina (S. ×pendulina). Salix ×sepulcralis, especially nothovar. chrysocoma, with bright yellow branchlets, is the most commonly grown of these hybrids. All reported occurrences of S. babylonica need verification.

Hybrids:

Salix ×sepulcralis Simonkai: Weeping willow, S. alba × S. babylonica, is introduced from Europe and widely naturalized throughout the world. Synonyms include S. ×salamonii Carrière ex Henry and S. ×sepulcralis nothovar. chrysocoma (Dode) Meikle. It is characterized by: trees, to 12 m, stems pendulous; branches somewhat to highly brittle at base, yellowish, yellow-green, or yellow-brown; branchlets yellowish, yellow-green, or golden; stipules rudimentary or foliaceous on late leaves; petiole not glandular or with pairs or clusters of spherical glands distally or scattered throughout, short-silky adaxially; largest medial blade amphistomatous or hemiamphistomatous, narrowly elliptic to very narrowly so, margins finely serrulate or spinulose-serrulate, abaxial surface glaucous, adaxial glaucous, sparsely long-silky to glabrescent, hairs white or white and ferruginous, adaxial surface slightly glossy; catkins on distinct flowering branchlet 3–14 mm; staminate moderately densely flowered, slender, 23–53 × 3–9 mm; pistillate moderately densely to loosely flowered, slender to stout, 18–30 × 3–8 mm, flowering branchlet 3–14 mm; pistillate bracts persistent after flowering; staminate abaxial and adaxial nectaries distinct; stamens 2; anthers 0.5–0.8 mm; pistillate nectary longer than stipe; stipe 0–0.2 mm; ovaries gradually tapering to styles; ovules 4 per ovary; styles 0.15–2 mm; capsules 1–2 mm. In the flora area, it occurs in: British Columbia, New Brunswick, Nova Scotia, Ontario, Quebec; Alaska, Arizona, Arkansas, California, Connecticut, District of Columbia, Illinois, Iowa, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Missouri, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Carolina, Ohio, Oregon, Pennsylvania, Tennessee, Utah, Virginia, and West Virginia.

The most commonly cultivated, and sometimes escaped, weeping willow with golden or yellow-green branchlets is Salix ×sepulcralis nothovar. chrysocoma (Dode) Meikle. It probably originated as S. alba var. vitellina × S. babylonica (R. D. Meikle 1984). According to F. S. Santamour Jr. and A. J. McArdle (1988), S. ×sepulcralis cv. Salamonii has a broadly pyramidal crown and is only slightly pendulous. It is not clear just how this cultivar differs from S. ×pendulina. For a discussion of the taxonomy of these and other weeping willows see J. Chmela (1983).

Salix ×pendulina Wenderoth: Weeping willow, S. babylonica × S. euxina, is introduced from Europe and grown throughout the world. It is characterized by: trees, 2.5–12 m, stems pendulous; branches highly brittle at base, yellow-brown, gray-brown, or red-brown; branchlets yellowish to brownish; stipules foliaceous on late leaves; petioles glabrous, pilose, or velvety to glabrescent adaxially; largest medial blade amphistomatous or hypostomatous, very narrowly elliptic to lanceolate, or linear, margins serrulate, irregularly so, or spinulose-serrulate, abaxial surface glaucous, adaxial slightly glossy or dull; catkins on distinct flowering branchlet, 3–14 mm; staminate loosely flowered, stout, 16–34 × 7–11 mm; pistillate densely or moderately densely flowered, slender or stout, 20–36 × 3.5–11 mm; pistillate bract persistent after flowering; staminate abaxial and adaxial nectaries connate and shallowly cup-shaped; stamens 2; anthers 0.5–0.6 mm; pistillate nectary longer than stipe; stipe 0 mm; styles 0.2–0.6 mm; ovules 4–8 per ovary; capsules 1.8–3.5 mm. In the flora area, it occurs in: Ontario; California, Connecticut, District of Columbia, Georgia, Illinois, Indiana, Maine, Maryland, Massachusetts, Michigan, Missouri, Nebraska, New Jersey, New Mexico, New York, North Carolina, Ohio, Oregon, Pennsylvania, Texas, Virginia, Washington, and West Virginia.

Reports of this hybrid in British Columbia and California are undocumented. Plants of Salix ×pendulina with prominent, caudate stipules are var. blanda (Andersson) Meikle; those with ovaries with patchy or streaky hairiness are var. elegantissima (K. Koch) Meikle.

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

Salix pedicellaris is found in Nunavut on Akimiski Island in James Bay and on the Belcher Islands in Hudson Bay.

Salix pedicellaris is very distinct with decumbent habit, leathery, glabrous leaves that are glaucous on both surfaces, loosely flowered catkins, ovaries reddish, glabrous and often glaucous, and stipes 2.1–3.2 mm. In the flora area, it hybridizes with six other species (see below). This compares with the closely related European S. myrtilloides Linnaeus, which is reported (B. Jonsell and T. Karlsson 2000+, vol. 1) to hybridize with seven species. The distinctive appearance may make hybrids easily recognizable but it is complex cytologically.

Hybrids:

Salix pedicellaris forms natural hybrids with S. arctica, S. argyrocarpa, S. athabascensis, S. chlorolepis, S. glauca var. cordifolia, S. pedicellaris, and S. pellita. Hybrids with S. candida and S. eriocephala have been reported (M. L. Fernald 1950) but no convincing specimens have been seen.

Salix pedicellaris × S. pellita (S. ×jamesensis Lepage) was described from the west coast of James Bay, Ontario. It is to be expected throughout northern Ontario and Quebec. According to E. Lepage (1964), its yellowish midveins and the hairiness of floral bracts superficially resemble those of S. pellita forma psila C. K. Schneider (syn. S. pellita forma denudata), but its reticulate leaf venation resembles that of S. pedicellaris.

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

Source FNA vol. 7, p. 40. FNA vol. 7, p. 83.
Parent taxa Salicaceae > Salix > subg. Salix > sect. Subalbae Salicaceae > Salix > subg. Chamaetia > sect. Myrtilloides
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. 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
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. 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. myrtilloides var. hypoglauca, S. pedicellaris var. hypoglauca, S. pedicellaris var. tenuescens
Name authority Linnaeus: Sp. Pl. 2: 1017. (1753) Pursh: Fl. Amer. Sept. 2: 611. (1813)
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