Salix hookeriana Barratt ex Hook. (redirected from: Salix hookeriana var. laurifolia)
Family: Salicaceae
[Salix amplifolia Coville,  more...]
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Shrubs or trees, (0.6-)2-8 m, (sometimes forming clones by layering or stem fragmentation). Stems: branches (highly brittle at base), yellow-brown, gray-brown, red-brown, or violet, not or weakly glaucous, glabrous, tomentose, woolly, or sparsely villous to glabrescent (nodes hairy); branchlets gray-brown, red-brown, or yellow-brown (sometimes color obscured by hairs), glabrous, pilose, moderately densely villous, tomentose, or woolly, scale with inner membranaceous layer free, not separating from outer layer). Leaves: stipules rudimentary or absent on early ones, foliaceous (early deciduous) or rudimentary (sometimes obscured) on late ones, (2.5-7.8-18 mm), apex acuminate, acute, or rounded; petiole convex to flat, or shallowly grooved adaxially, 4-29 mm, villous, woolly, pilose, or tomentose adaxially; largest medial blade (sometimes hemiamphistomatous), narrowly to broadly elliptic, oblanceolate, or obovate to broadly obovate, 36-123 × 18-63 mm, 1.5-4.2 times as long as wide, base convex, rounded, subcordate, cordate, or cuneate, margins slightly revolute, crenate, serrate, shallowly serrulate, sinuate, or entire, apex acuminate, acute, or convex, abaxial surface glaucous, pilose, moderately densely tomentose, villous, or woolly, midrib hairy, hairs (white, sometimes also ferruginous), wavy or straight, adaxial highly or slightly glossy, glabrous, pilose, villous, or moderately densely tomentose, midrib and veins hairy (hairs white, sometimes also ferruginous); proximal blade margins entire or shallowly serrulate; juvenile blade yellowish, reddish green (sometimes obscured by hairs), pilose or sparsely to densely long-silky, tomentose, woolly, or villous abaxially, hairs white, sometimes also ferruginous, or yellowish. Catkins flowering before or as leaves emerge; staminate slender or stout, 26-73 × 10-27 mm, flowering branchlet 0-10 mm; pistillate densely flowered, slender or stout, 36-92(-140 in fruit) × 10-25 mm, flowering branchlet 0-20 mm; floral bract brown, black, or bicolor, 1.1-3.6 mm, apex convex, rounded, or acute, abaxially hairy, hairs straight or wavy. Staminate flowers: adaxial nectary oblong, ovate, or narrowly oblong, 0.5-1.4 mm; filaments distinct or slightly basally connate, glabrous or hairy on proximal 1/2 or basally; anthers yellow, cylindrical or ellipsoid, (0.5-)0.7-1 mm. Pistillate flowers: adaxial nectary narrowly oblong, oblong, or square, 0.5-1.4 mm, shorter than stipe; stipe 0.5-1.8(

Flowering mid Apr-mid Jun. Marine coastal beaches and sand dunes, interdunal depressions, coastal marshes, pine barrens, floodplains, ravines, wet sedge meadows, lakeshores, morainal flats, sandy or gravelly substrates; 0-1800 m; B.C.; Alaska, Calif., Oreg., Wash.

Salix hookeriana is primarily a coastal species occurring from northern California northward to Oregon, Washington, and southern Vancouver Island, with disjunct populations on Queen Charlotte Islands, British Columbia, and northward to Yakatut Bay, Turnagain Arm, and Kodiak, Alaska. It was treated by G. W. Argus (1973) and R. D. Dorn (2000) in a broad sense because of an absence of strong distinguishing characters and intergradation in characters that could be used to divide it. It is highly variable and three very similar taxa have been named: S. amplifolia, S. hookeriana (including vars. tomentosa and laurifolia), and S. piperi. Although extremes of these taxa sometimes are recognizable, the intergradation displayed is so great that even attempts to recognize them as varieties are thwarted. The amplifolia variant in Alaska is characterized by having only white leaf hairs, hairy ovaries, no stipules, and catkins often borne on distinct flowering branchlets, but variation can occur within the same population, and typical S. hookeriana on Vancouver Island sometimes displays the same characteristics. The piperi variant, an inland population in western Oregon and Washington, is usually recognized by local botanists as different from coastal populations. It is characterized by leaves and branchlets soon becoming glabrate and stipules prominent. These characteristics, however, sometimes appear in northern California coastal populations, and some inland populations in Oregon include very hairy individuals that are indistinguishable from coastal variants of S. hookeriana. In general, very hairy populations of S. hookeriana are probably an adaptation to marine coastal environments, but some variation may be due to hybridization and introgression with S. scouleriana. Inland populations suggest the influence of S. lasiolepis. Two hexaploid chromosome numbers reported for S. hookeriana from Vancouver Island (R. L. Taylor and S. Taylor 1977) and Queen Charlotte Islands (R. L. Taylor and G. A. Mulligan 1968), British Columbia, indicate that hybridization has played a role in the evolution of this complex. It is possible that each variant of S. hookeriana has had a different, possibly even recurrent, polyploid origin. Further cytological and genetic study is indicated.

The following comparisons may help to distinguish Salix hookeriana, S. lasiolepis, and S. s