Salix humboldtiana |
Salix myrsinifolia |
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Humboldt's willow |
dark-leaf willow, myrsine-leaf willow |
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Stems | branches dark red-brown or gray-brown, not glaucous, glabrous or hairy, (peeled wood smooth or striate with relatively few, short striae); branchlets red-brown, moderately to very densely pubescent or velvety. |
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Leaves | stipules usually foliaceous, sometimes minute rudiments on early ones, foliaceous on late ones, (ca. 4 mm), apex acute; petiole convex to flat, or shallowly grooved adaxially, 3.5–12(–15) mm, villous to puberulent adaxially; largest medial blade (sometimes hemiamphistomatous), broadly obovate, elliptic, broadly elliptic, or subcircular, 24–52(–100) × 12–45 mm, base concave, rounded, subcordate, cordate, or cuneate, margins sometimes slightly revolute, serrulate, or crenulate to subentire, apex abruptly acuminate or acute, abaxial surface glaucous (tip often not glaucous), sparsely to moderately densely puberulent, or silky to glabrescent, hairs appressed or spreading, straight or wavy, adaxial slightly glossy, glabrescent or sparsely to moderately densely puberulent, pubescent, or short-silky (especially midrib); proximal blade margins serrulate, crenulate, or entire; juvenile blade sometimes reddish, long-silky, villous, tomentose (at least on midrib), or glabrous abaxially, hairs usually white, rarely somewhat ferruginous. |
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Staminate flowers | adaxial nectary 0.5–0.7 mm; filaments distinct; anthers purple turning yellow, (ellipsoid or shortly cylindrical), 0.5–0.8 mm. |
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Pistillate flowers | adaxial nectary ovate, square, or flask-shaped, 0.4–0.6(–1) mm; ovary pyriform, pubescent throughout or in patches or streaks, or glabrous (hairs refractive), beak gradually tapering to styles; ovules 12–14 per ovary; styles 0.6–1.5 mm. |
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Capsules | 6–10 mm. |
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Salix | humboldtiana Willdenow: Humboldt willow is not known to occur in the flora area. |
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It | is characterized by: trees, 4–25 m; branches highly brittle at base, bud-scale margins distinct and overlapping adaxially; stipules on late leaves rudimentary or foliaceous; largest medial leaf blade usually linear, abaxial surface not glaucous, adaxial dull; pistillate bract deciduous after flowering; stamens 3–7; capsules with distinct, often raised, white veins.; it occurs throughout much of Mexico to central Chile. |
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Catkins | flowering as leaves emerge; staminate (densely flowered), stout or subglobose, 17–35 mm, flowering branchlet 1–3 mm; pistillate densely flowered, stout, 9–11(–30)(–80 in fruit) mm, flowering branchlet 2–5.5 mm; floral bract pale brown, 1–1.9(–2.8) mm, apex acute, convex, or rounded, abaxially sparsely hairy, hairs straight or wavy. |
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2n | = 114. |
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Salix humboldtiana |
Salix myrsinifolia |
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Phenology | Flowering mid Mar-mid Jun. | |
Habitat | Roadsides, waste places | |
Elevation | ca. 100 m (ca. 300 ft) | |
Distribution |
Mexico to central Chile |
ON; Eurasia [Introduced in North America] |
Discussion | Salix humboldtiana is closely related to S. nigra in its generally narrow leaf blades, which are not glaucous abaxially. The two differ in the following characters: S. humboldtiana has leaf blades linear to sometimes narrowly oblong (10–28.6 times as long as wide), ovaries usually ovoid to ellipsoid, ovary walls often stomatiferous and with raised, white veins, and capsule valves relatively thick, slightly recurved. S. nigra has leaf blades usually narrowly lanceolate (6–13 times as long as wide), ovaries pyriform to obclavate, ovary walls neither stomatiferous nor notably veined, and capsule valves relatively thin and strongly recurved. Both species occur in Chihuahua, Mexico. The report by R. I. Lonard et al. (1991) that specimens identified as Salix nigra from the lower Rio Grande, Texas, resemble S. humboldtiana in having strongly veined capsules suggests that S. humboldtiana, or intergrades with that species, may occur in Texas. Attempts to locate a voucher specimen were unsuccessful; because strongly veined capsules are diagnostic, further field study is indicated. An earlier name, Salix chilensis Molina, has been applied to this species; it does not seem to pertain to this taxon (C. K. Schneider 1918). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Salix myrsinifolia may be naturalized in the vicinity of Ottawa, Ontario, but that needs confirmation. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 34. | FNA vol. 7, p. 125. |
Parent taxa | Salicaceae > Salix > subg. Protitea > sect. Humboldtianae | Salicaceae > Salix > subg. Vetrix > sect. Nigricantes |
Sibling taxa | ||
Synonyms | S. nigricans | |
Name authority | Willdenow | Salisbury: Prodr. Stirp. Chap. Allerton, 394. (1796) |
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