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Pacific willow (var. lasiandra), shining willow, whiplash willow (ssp. caudata)

Idaho willow, wolf willow, Wolf's willow

Habit Shrubs or trees, 4–6 m. Stems: branches flexible to highly brittle at base, yellow-brown, gray-brown, or red-brown, slightly to highly glossy, glabrous or villous to glabrescent; branchlets yellow-brown, gray-brown, or red-brown, glabrous, pilose, densely villous, or velvety, hairs spreading, straight, wavy, or crinkled. Plants 0.1–2 m. Stems: branches red-brown, violet, yellow-gray, or yellow-brown, pubescent or pilose to glabrescent; branchlets yellowish, yellow-brown, red-brown, or yellow-green, sparsely or moderately densely pubescent, or densely long-silky, (inner membranaceous bud-scale layer free, separating from outer layer).
Leaves

stipules foliaceous, apex convex to rounded;

petiole shallowly to deeply grooved adaxially, 5–13 mm, with clusters of spherical or foliaceous glands distally, glabrous, pilose, or densely villous adaxially;

largest medial blade usually hypostomatous or hemiamphistomatous, rarely amphistomatous, lorate, very narrowly elliptic, narrowly elliptic, or lanceolate, (24–)55–133 × 11–43 mm, 2.5–6.2 times as long as wide, base convex or cuneate, margins flat, serrulate, apex acuminate to caudate, abaxial surface usually not glaucous (rarely so), glabrous, pilose, or moderately densely villous or long-silky, hairs appressed or spreading, white and/or ferruginous, straight or wavy, (coarse, caducous), adaxial (secondary veins flat or protruding), slightly or highly glossy, glabrous, pilose, or long-silky, hairs white and/or ferruginous;

proximal blade margins entire and glandular-dotted, or serrulate or crenulate;

juvenile blade reddish or yellowish green, glabrous or densely villous or long-silky abaxially, hairs white and ferruginous.

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

petiole convex to flat, or shallowly grooved adaxially, 3–12 mm, pubescent, long-silky, or villous adaxially;

largest medial blade narrowly oblong, narrowly elliptic, elliptic, or oblanceolate, 26–56 × 8–16.5 mm, 2.5–3.7–5.6 times as long as wide, base cuneate, convex, or rounded, margins flat, entire, apex acute, acuminate, or convex, abaxial surface not glaucous, pubescent, short-silky, or villous, hairs appressed or spreading, straight or wavy, adaxial dull, sparsely to densely silky or villous;

proximal blade margins entire;

juvenile blade yellowish green, densely short- or long-silky or villous abaxially, hairs white.

Staminate flowers

abaxial nectary 0.5–1.1 mm, adaxial nectary square or ovate, 0.3–0.9 mm, nectaries connate and cup-shaped;

stamens 3–6;

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

anthers ellipsoid, shortly cylindrical, obovoid, or globose, 0.6–0.8 mm.

(abaxial nectary 0–0.2 mm), adaxial nectary oblong, 0.4–1.1 mm, (nectaries distinct);

filaments distinct, glabrous;

anthers yellow, 0.3–0.5 mm.

Pistillate flowers

adaxial nectary square or ovate, (swollen), 0.2–0.5 mm, shorter than stipe;

stipe 0.5–2 mm;

ovary pyriform, beak slightly bulged below or gradually tapering to styles;

ovules 18–24 per ovary;

styles connate or distinct 1/2 their lengths, 0.5–0.8 mm;

stigmas flat, abaxially non-papillate with rounded tip, broadly cylindrical, or 2 plump lobes, 0.24–0.31–0.42 mm.

adaxial nectary oblong, ovate, or flask-shaped, 0.4–1.1 mm, shorter to longer than stipe;

stipe 0.2–0.9 mm;

ovary pyriform, glabrous or hairy, beak gradually tapering to or slightly bulged below styles;

ovules 8–16 per ovary;

styles 0.3–1 mm;

stigmas flat, abaxially non-papillate with rounded or pointed tip, or slenderly or broadly cylindrical, 0.24–0.3–0.4 mm.

Capsules

5–7 mm.

3–5 mm.

Catkins

staminate 19–69 × 4–14 mm, flowering branchlet 5–23 mm; pistillate (fruiting in summer), moderately densely to loosely flowered, slender to stout, 23–56(–70 in fruit) × 8–12 mm, flowering branchlet 8–25 mm;

floral bract 1.5–3 mm, apex convex or rounded, entire or toothed, abaxially sparsely hairy throughout or proximally, hairs wavy.

flowering as leaves emerge; staminate stout or subglobose, 9.5–16 × 6–12 mm, flowering branchlet 1–5.5 mm; pistillate moderately or very densely flowered, stout, subglobose or globose, 8.5–38 × 5–12 mm, flowering branchlet 1–11 mm;

floral bract brown, black, or bicolor, 0.8–2 mm, apex rounded or acute, abaxially hairy, hairs wavy, straight, or curly.

2n

= 76.

Salix lucida

Salix wolfii

Phenology Flowering early May-mid Jul.
Habitat Sandy or gravelly floodplains, lake margins, sedge meadows, vernal pools, alvars, open fens, marl bogs, treed bogs
Elevation 0-600 m (0-2000 ft)
Distribution
from FNA
CT; DE; IA; IL; IN; MA; MD; ME; MI; MN; ND; NH; NJ; NY; OH; PA; RI; SD; VA; VT; WI; WV; MB; NB; NL; NS; ON; PE; QC; SK; SPM
[WildflowerSearch map]
[BONAP county map]
from FNA
CO; ID; MT; NV; OR; UT; WY
[WildflowerSearch map]
[BONAP county map]
Discussion

The Virginia plants of Salix lucida are introduced (G. W. Argus 1986).

The Salix lucida complex is a group of three weakly delimited taxa, S. lasiandra var. caudata, S. lasiandra var. lasiandra, and S. lucida. The morphological characters used to separate them (leaves amphistomatous or hypostomatous and blades glaucous abaxially or not) are usually geographically correlated, but there are exceptions. G. W. Argus (1986b) proposed, based on principal components analysis of morphological data, to treat them as a single species consisting of three subspecies. The geographic overlap of the northeastern S. lucida and the western S. lasiandra is a relatively small area in central Saskatchewan. Evidence of intergradation was based on cultivation of a plant that, in the wild, had leaves that were not glaucous abaxially but were glaucous in cultivation. It seems best to treat them as two species, S. lucida and S. lasiandra, the latter with two varieties, var. lasiandra and var. caudata.

Hybrids:

Salix lucida forms natural hybrids with S. alba and S. nigra. Hybrids with S. serissima have been reported (M. L. Fernald 1950) but no convincing specimens have been seen. Attempts to hybridize S. lucida with members of subg. Protitea (S. amygdaloides), subg. Longifoliae (S. interior), and subg. Vetrix (S. discolor, S. eriocephala, and S. petiolaris) were unsuccessful (A. Mosseler 1990).

Salix lucida × S. nigra (S. ×schneideri B. Boivin) seems to be a rare intersubgeneric hybrid between tetraploid S. lucida and diploid S. nigra. It is known only from the type specimen, an infertile plant, growing with both parents. It resembles S. lucida in bud-scale margins connate, in petiolar glands stalked or foliaceous, and in leaf shape, and S. nigra in stipules rudimentary on proximal leaves and sometimes even on early leaves, stipule apex acute, pistillate catkins relatively long and slender, and styles relatively short.

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

Varieties 2 (2 in the flora).

The two varieties of Salix wolfii are distinguished mainly by ovary hairiness; other characters in the key overlap. Ovaries of the typical var. wolfii are glabrous and those of var. idahoensis are hairy. In the latter variety, ovaries are sometimes hairy throughout, but most have hairs in streaks or in a patch at the base of the ovary and on the stipes. These plants usually do not set seed and may be infertile hybrids. Occasional occurrence of staminate flowers with abaxial nectaries suggests that this variety may be a hybrid with S. glauca or S. brachycarpa, although it could also be with S. eastwoodiae, as suggested by S. J. Brunsfeld and F. D. Johnson (1985). The presence of both abaxial and adaxial nectaries in staminate flowers of S. wolfii (staminate plants cannot be identified to variety) is an unusual character in subg. Vetrix; it rarely occurs in S. argyrocarpa, S. breweri, and S. orestera, but is common in S. wolfii. Both hairy ovaries and abaxial nectaries could have been acquired through hybridization and introgression, or polyploidy, with S. glauca or S. brachycarpa. Cytological study of S. wolfii may help answer this question.

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

Key
1. Ovaries glabrous; pistillate adaxial nectaries 0.4-0.8 mm; stipes 0.2-0.9 mm.
var. wolfii
1. Ovaries pubescent or tomentose (hairs in streaks or patches); pistillate adaxial nectaries 0.4-1.1 mm; stipes 0-0.4 mm
var. idahoensis
Source FNA vol. 7, p. 46. FNA vol. 7, p. 107.
Parent taxa Salicaceae > Salix > subg. Salix > sect. Salicaster Salicaceae > Salix > subg. Vetrix > sect. Hastatae
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. 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. 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. ×fragilis, S. ×jesupii, S. ×pendulina, S. ×sepulcralis, S. ×smithiana
Subordinate taxa
S. wolfii var. idahoensis, S. wolfii var. wolfii
Synonyms Pleiarina lucida, S. lucida var. angustifolia, S. lucida var. intonsa
Name authority Muhlenberg: Ges. Naturf. Freunde Berlin Neue Schriften 4: 239, plate 6, fig. 7. (1803) Bebb: in J. T. Rothrock, Rep. U. S. Geogr. Surv., Wheeler, 241. (1879)
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