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sandbar willow

hoary willow, sage willow, sage-leaf willow

Habit Shrubs or trees, 4–9 m. Stems: branches gray-brown to red-brown, glabrous or villous; branchlets yellow brown to red-brown, densely tomentose or villous to glabrescent. Plants often forming clones by layering.
Stems

branches dark gray-brown to yellow-brown, not glaucous, woolly in patches or floccose to glabrescent;

branchlets yellow-brown to red-brown or gray-brown, densely (white) woolly or tomentose, sometimes floccose.

Leaves

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

petiole 1–5(–9) mm, glabrous or sparsely villous adaxially;

largest medial blade linear to lorate, 60–160 × 4–11 mm, (6.5–)11–19(–31) times as long as wide, base cuneate, margins flat, remotely spinulose-serrulate (teeth 2–5 per cm), apex acute or subacuminate, abaxial surface thinly glaucous, densely villous or long-silky to glabrescent, adaxial slightly glossy, pilose or densely villous to glabrescent;

proximal blade margins entire;

juvenile blade reddish or yellowish green, moderately densely to sparsely long-silky abaxially.

stipules rudimentary or foliaceous on early ones, late ones 2–3.6 mm, apex acute;

petiole shallowly to deeply grooved adaxially, 3–10 mm, tomentose or densely (white) woolly adaxially (obscured by hairs);

largest medial blade lorate, narrowly elliptic or oblanceolate, 47–103 × 5–20 mm, base convex or cuneate, margins strongly to slightly revolute, entire, or sinuate, apex acute or convex, abaxial surface glaucous (generally obscured by hairs), very densely to sparsely tomentose-woolly (cobwebby in age), hairs dull white, crinkled, adaxial dull or slightly glossy, moderately densely to sparsely tomentose, floccose, hairs dull white;

proximal blade margins entire;

juvenile blade yellowish green, very densely tomentose abaxially, hairs white.

Staminate flowers

abaxial nectary 0.5–1.1 mm, adaxial nectary ovate, narrowly oblong, or flask-shaped, 0.6–1.4 mm, nectaries distinct;

filaments hairy;

anthers 0.4–0.9 mm.

adaxial nectary narrowly oblong to oblong, 0.6–1 mm;

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

anthers purple turning yellow, ellipsoid, long-cylindrical, or globose, 0.4–0.6 mm.

Pistillate flowers

adaxial nectary narrowly oblong, 0.4–1.1 mm, shorter to longer than stipe;

stipe 0.4–0.8 mm;

ovary obclavate to pyriform, glabrous, glabrescent, or long-silky, beak abruptly tapering to styles;

ovules 16–36 per ovary;

styles 0–0.2 mm;

stigmas flat, abaxially non-papillate with pointed tip, or broadly cylindrical, 0.3–0.7 mm.

adaxial nectary oblong, 0.4–1 mm;

ovary pyriform, beak sometimes slightly bulged below styles;

ovules 12–18 per ovary;

styles 0.3–1.9 mm.

Capsules

(4–)5–8(–10) mm.

4–6 mm.

Catkins

(flowering throughout season); staminate 20–61 × 4–10 mm, flowering branchlet 3–20 mm; pistillate loosely flowered, slender or stout, 20–67 × 5–9 mm, flowering branchlet 3–19 mm;

floral bract (sometimes greenish), 1.5–3.5 mm, apex acute, acuminate, or rounded, entire, erose, or toothed, abaxially hairy either proximally or distally, hairs wavy.

flowering as leaves emerge; staminate stout or subglobose, 17–39 × 8–16 mm, flowering branchlet 0.5–7 mm; pistillate densely to moderately densely flowered, stout or slender, 20–66 × 9–18 mm, flowering branchlet 1–24 mm;

floral bract tawny or brown, 1.2–1.8 mm, apex rounded or acute, abaxially hairy, hairs straight to wavy.

2n

= 38.

= 38.

Salix interior

Salix candida

Phenology Flowering early Apr-early Jul. Flowering mid Apr-early Jul.
Habitat Sandy to silty flood plains, margins of lakes, ponds, and prairie sloughs, dry prairie sand hills, marshes, disturbed areas Floodplains, marl bogs, fens, and meadows, calcareous substrates
Elevation 10-1800 m (0-5900 ft) 10-2800 m (0-9200 ft)
Distribution
from FNA
AK; AR; CO; CT; DC; DE; IA; IL; IN; KS; KY; LA; MD; ME; MI; MN; MO; MS; MT; ND; NE; NJ; NY; OH; OK; PA; SD; TN; TX; VA; WI; WV; WY; AB; BC; MB; NB; NT; ON; QC; SK; YT; Mexico (Tamaulipas, Veracruz)
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from FNA
AK; CO; CT; IA; ID; IL; IN; MA; ME; MI; MN; MT; ND; NH; NJ; NY; OH; PA; SD; VT; WA; WI; WY; AB; BC; MB; NB; NL; NS; NT; NU; ON; PE; QC; SK; YT; SPM
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Discussion

Sometimes Salix interior is treated as a subspecies of S. exigua (R. D. Dorn 1998). Salix exigua and S. interior hybridize and apparently intergrade in the western Great Plains; because the area of overlap is relatively small and distinctiveness of the two taxa is not compromised by hybridization and introgression, it is best to treat them as separate species.

Leaves on sylleptic shoots are usually very densely silky. Salix interior sometimes has shoots that arise from buds on either side of the normal axillary bud. They do not seem to be directly related to the stipules because they are enclosed by the petiole. Catkins with both staminate and pistillate flowers are rare in S. interior, but a Quebec specimen had some catkins predominantly pistillate and others staminate; most were a mixture. The flowers were not teratological, but a mature capsule contained aborted ovules.

Hybrids:

Salix interior forms natural hybrids with S. exigua var. exigua. Controlled pollinations using S. interior (as S. exigua) from southern Ontario (A. Mosseler 1990) successfully produced F1 hybrids with S. bebbiana, S. discolor, S. eriocephala, and S. petiolaris. Seed production was usually relatively low, except in crosses with S. discolor. In general, F1 viability was relatively low in crosses with these members of subg. Vetrix. No seeds were produced in crosses with members of subgenera Protitea or Salix. Morphology of the hybrids usually was intermediate between the two parents, but when S. petiolaris was used as the maternal parent, the F1s more closely resembled that species. J. Salick and E. Pfeffer (1999) extended these findings to show that, although crosses between S. interior (as S. exigua) and S. eriocephala are partially sterile, their clonal growth parameters (sprouting, shoot length, and biomass production) are strong and thus permit these partially sterile hybrids to exist as successful individuals and perhaps to “... make a contribution to interspecific gene flow over time.” Of particular taxonomic interest is that, in this cross, the staminate parent has a significant influence on leaf shape, whereas in the cross S. eriocephala × S. petiolaris it is the pistillate parent that is significant for leaf shape. Relatively few hybrids resembling those produced by Mosseler have been recognized in nature, but it is possible that the unusually broadly leaved plants named S. interior var. exterior and var. wheeleri, from northern Maine, Nebraska, New York, and West Virginia, and probably elsewhere, may be hybrids. Phenological isolation may be strong enough to prevent crosses in nature (A. Mosseler and C. S. Papadopol 1989) with the earlier flowering S. eriocephala and S. petiolaris, a barrier that even an occasional period of overlap cannot breach.

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

Occurrence of Salix candida in Nunavut is on Akimiski Island in James Bay.

Salix candida is geographically wide-ranging but limited to calcareous habitats and, for that reason, it is quite local or even rare in some parts of its range.

Hybrids:

Salix candida forms natural hybrids with S. bebbiana, S. brachycarpa var. brachycarpa, S. calcicola, S. eriocephala, S. famelica, S. myrtillifolia, S. petiolaris, and S. planifolia. Hybrids with S. discolor, S. petiolaris, and S. sericea have been reported (the latter also by C. K. Schneider 1921; M. L. Fernald 1950) but no convincing specimens have been seen. Salix candida hybrids are recognized from their woolly indumentum that often is conspicuous on leaves, stems, and ovaries. In hybrids, these characters, especially woolly patches on ovaries, stand out as discordant variation.

Salix candida × S. eriocephala (S. ×rubella Bebb ex C. K. Schneider) was described by W. W. Rowlee and K. M. Wiegand (1896) as S. candida × S. cordata. In addition to woolly patches on the ovaries, they noted that buds of the hybrids usually are shorter, more divergent, and blunter than those in S. eriocephala, and are glabrous or hairy. Known from New York and Newfoundland; it should be expected throughout the sympatric range of the parental species.

Salix candida × S. famelica: The Saskatchewan specimen resembles S. famelica but has the leaf indumentum of S. candida.

Salix candida × S. myrtillifolia: Saskatchewan specimens combine characters of the two parents.

Salix candida × S. petiolaris: Intermediates between these species are known from Michigan and New York (W. W. Rowlee and K. M. Wiegand 1896) as well as Ontario and Saskatchewan, but can be expected wherever the two grow together. The invalid name “S. ×clarkei” is sometimes used for this hybrid.

The glabrescent form of Salix candida, forma denudata (Andersson) Rouleau, may be of hybrid origin.

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

Source FNA vol. 7, p. 56. FNA vol. 7, p. 141.
Parent taxa Salicaceae > Salix > subg. Longifoliae Salicaceae > Salix > subg. Vetrix > sect. Candidae
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. 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. 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. rubra, S. exigua var. exterior, S. exigua subsp. interior, S. exigua var. pedicellata, S. exigua var. sericans, S. fluviatilis var. sericans, S. interior var. exterior, S. interior var. pedicellata, S. interior var. wheeleri, S. linearifolia, S. longifolia var. interior, S. longifolia var. pedicellata, S. longifolia var. sericans, S. longifolia var. wheeleri, S. wheeleri S. candida var. denudata
Name authority Rowlee: Bull. Torrey Bot. Club 27: 253. (1900) Flüggé ex Willdenow: Sp. Pl. 4: 708. (1806)
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