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basket willow, common osier, osier, osier willow, silky osier

blue-stem willow, dewy-stem willow

Habit Shrubs, 2–7 m, (multistemmed, sometimes forming clones by stem fragmentation).
Stems

branches yellow-brown, gray-brown, or yellowish, not glaucous, glabrous or puberulent;

branchlets yellow-brown or yellowish (sometimes color obscured by hairs), glabrous, densely to sparsely villous, velvety, or puberulent.

branches (highly brittle or not at base), red-brown to violet, usually glaucous, glabrous;

branchlets yellow-brown, (strongly glaucous or not), glabrous, sparsely velvety, or tomentose.

Leaves

stipules (not adnate to petioles), rudimentary or absent on early ones, (late ones sometimes brownish, linear, 5.4–10.4 mm), apex acuminate;

petiole shallowly grooved adaxially, 4–13 mm, villous, puberulent, or velvety adaxially;

largest medial blade linear, lorate, narrowly oblong, or narrowly elliptic, 53–130 × 5–33 mm, base cuneate, margins strongly revolute, sinuate or apparently entire, (glands epilaminal), apex acuminate, acute, or convex, abaxial surface apparently glaucous (obscured by hairs), densely short-silky, woolly, or tomentose, (midribs prominent, yellowish, and hairy), hairs appressed, spreading or erect, straight or wavy, adaxial dull or slightly glossy, sparsely or moderately densely pubescent, hairs gray;

proximal blade margins entire;

juvenile blade yellowish green, very densely tomentose or short-silky abaxially, hairs white.

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

petiole convex to flat adaxially, 4–14 mm, velvety adaxially;

largest medial blade lorate, narrowly oblong, narrowly elliptic, or narrowly oblanceolate, 47–115 × 8–22 mm, 3.5–7.7 times as long as wide, base cuneate or convex, margins flat to slightly revolute, entire and gland-dotted, serrulate or crenate, apex acuminate, acute, or convex, abaxial surface glaucous, glabrous, sparsely tomentose, or short-silky, hairs wavy, adaxial slightly to highly glossy, glabrous or pilose;

proximal blade margins entire or serrulate;

juvenile blade yellowish green or reddish, glabrous or sparsely villous abaxially, hairs white.

Staminate flowers

adaxial nectary narrowly oblong or oblong, 0.6–1.5 mm;

filaments distinct;

anthers purple turning yellow, ellipsoid to shortly cylindrical, 0.6–0.8 mm.

adaxial nectary narrowly oblong to oblong, 0.3–0.8 mm;

filaments connate less than to more than 1/2 their lengths;

anthers yellow or purple turning yellow, ellipsoid or shortly cylindrical, 0.4–0.7 mm.

Pistillate flowers

adaxial nectary narrowly oblong or oblong, 0.9–1.4 mm;

ovary pyriform, beak gradually tapering to styles;

ovules 12–18 per ovary;

styles 0.6–1.8 mm.

adaxial nectary narrowly oblong to oblong, 0.3–0.7 mm;

stipe 0.4–1 mm;

ovary pyriform, beak slightly bulged below styles;

ovules 9–12 per ovary;

styles 0.3–0.9 mm;

stigmas flat, abaxially non-papillate with rounded tip, 0.15–0.28–0.6 mm.

Capsules

4–6 mm.

3.5–4 mm.

Catkins

flowering just before or as leaves emerge; staminate stout, 24–48 mm, flowering branchlet 0–2 mm; pistillate densely flowered, 23–55 mm, flowering branchlet 0–6 mm;

floral bract brown or tawny, 1.6–2.2 mm, apex convex or rounded, abaxially hairy, hairs straight.

flowering before or just before leaves emerge; staminate stout or subglobose, 15–34 × 8–22 mm, flowering branchlet 0(–2) mm; pistillate densely flowered, stout or slender, 14–43 × 7–12 mm, flowering branchlet 0–4 mm;

floral bract brown or black, 1.3–2.5 mm, apex rounded, abaxially hairy, hairs straight or wavy.

2n

= 38.

= 38.

Salix viminalis

Salix irrorata

Phenology Flowering Apr-early May. Flowering mid Mar-mid May.
Habitat Sandy, open woods, cobble rivershores, lake margins, and roadsides Streams, wet meadows
Elevation 0-300 m (0-1000 ft) 1400-3000 m (4600-9800 ft)
Distribution
from FNA
CT; IA; IN; MA; ME; NJ; NY; OH; RI; VT; NB; NF; NS; ON; PE; QC; Europe [Introduced in North America]
[BONAP county map]
from FNA
AZ; CO; NM; WY; Mexico (Baja California, Chihuahua, Coahuila, Durango, Sonora)
[WildflowerSearch map]
[BONAP county map]
Discussion

Salix ×smithiana (S. caprea × S. viminalis) is distinguished from S. viminalis by having leaf blades usually broad, 2.8–4.9(–6.4) times as long as wide, stipes 0.9–2 mm, ovaries short-silky, branches ± brittle at base, and petioles flat to convex adaxially; S. viminalis has leaf blades usually very narrow, 4.7–13.7 times as long as wide, stipes 0.1–0.5 mm, ovaries long-silky, branches flexible at base, and petioles shallowly grooved adaxially.

See Salix ×smithiana [p. 132] and 86. S. pellita for further comparative descriptions.

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

Salix irrorata is very closely related to S. lasiolepis. The two are here maintained as separate species primarily because S. irrorata is a diploid and S. lasiolepis a tetraploid, and also because of their largely allopatric ranges (G. W. Argus 2007). Studies of sawflies (Euura Newman) by P. W. Price (pers. comm.) show that the same species of Euura can successfully reproduce on either willow. The only morphological character that separates the two is that in S. irrorata branchlets and branches are very strongly glaucous, whereas in S. lasiolepis they are not glaucous. Some plants have weakly glaucous stems (wax not visible except by polishing or only as sparkling crystals); this may be infraspecific variability or evidence of hybridization.

Hybrids:

Salix irrorata forms natural hybrids with S. drummondiana, S. geyeriana, and S. lasiolepis var. lasiolepis.

Salix irrorata × S. lasiolepis var. lasiolepis: This putative hybrid occurs in Arizona and New Mexico. It is characterized mainly by weakly glaucous branches.

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

Source FNA vol. 7, p. 149. FNA vol. 7, p. 155.
Parent taxa Salicaceae > Salix > subg. Vetrix > sect. Viminella Salicaceae > Salix > subg. Vetrix > sect. Mexicanae
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. 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. 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. 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
Name authority Linnaeus: Sp. Pl. 2: 1021. (1753) Andersson: Öfvers. Kongl. Vetensk.-Akad. Förh. 15: 117. (1858)
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