Salix setchelliana

C. R. Ball

Univ. Calif. Publ. Bot. 17: 410, plate 72. 1934.

Common names: Setchell’s willow
IllustratedEndemic
Treatment appears in FNA Volume 7. Treatment on page 66. Mentioned on page 29, 51, 61, 67, 89.

Stems erect or semiprostrate; branches gray-brown or redbrown, glabrous or woolly to glabrescent; branchlets reddish, densely woolly (hairs spreading). Leaves: stipules absent or rudimentary; petiole (shallowly grooved adaxially), 0–3 mm; largest medial blade narrowly oblong, narrowly elliptic, elliptic, oblanceolate, or obovate, 25–87 × 10–30 mm, 2–3.9 times as long as wide, base cuneate or convex, margins flat, entire or serrulate, apex rounded to convex, abaxial surface glabrous, adaxial dull, glabrous; proximal blade margins entire or serrulate; juvenile blade glabrous. Catkins (sometimes branched); staminate 12–27 × 6–10 mm, flowering branchlet 3–8 mm; pistillate densely flowered, stout or subglobose, 20–34 × 6–13 mm, flowering branchlet 5–19 mm; floral bract tawny or greenish, translucent, 2–3.6 mm, apex rounded or truncate, erose, sinuate, irregularly toothed, or entire, abaxially glabrous. Staminate flowers: abaxial nectary 0.4–0.8 mm, adaxial nectary narrowly oblong, oblong, or ovate, 0.6–1 mm, nectaries distinct, or connate and shallowly cupshaped; filaments distinct, glabrous or hairy basally or on proximal 1/2; anthers long-cylindrical, 0.6–0.8 mm. Pistillate flowers: adaxial nectary oblong, 0.8–1.3 mm, equal to or longer than stipe; stipe 0–0.6 mm; ovary obclavate or ovoid, beak abruptly tapering to styles; ovules 16–23 per ovary; styles distinct, 0.3–0.4 mm; stigmas flat, abaxially non-papillate with pointed tip, or slenderly cylindrical, 0.32–0.47–0.6 mm. Capsules 3.6–10 mm. 2n = 38.


Phenology: Flowering late May-late Jun.
Habitat: Pioneer on sandy to gravelly beaches, bars along glacial streams, glacial moraine
Elevation: 10-1100 m

Discussion

Salix setchelliana shares some unique characters with members of subg. Longifoliae and some Populus. It produces shoots from roots, the catkins are sometimes branched, and the leaves are isolateral, with hypodermis present on both sides of the blade (W. Buechler, pers. comm.). While it is possible that these characters evolved independently, it is more likely that they were derived from a common ancestor.

Salix setchelliana is a highly successful colonizer of temporary gravel bar habitats. This is made possible by rapid expansion of its clones by root shoots and its ability to become established in new locations by both seedlings and clonal fragments (D. A. Douglas 1989).

Hybrids:

Salix setchelliana forms natural hybrids with S. niphoclada.

Selected References

None.

Lower Taxa

None.

"-0.6mm" is not declared as a valid unit of measurement for this property.

... more about "Salix setchelliana"
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
oblong +  and ovate +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.13 cm1.3 mm <br />0.0013 m <br />) +
red turning yellow +
long-cylindrical +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
entire +, toothed +, sinuate +, rounded +  and convex +
George W. Argus +
C. R. Ball +
convex +  and cuneate +
Salix sect. Chamaetia +
tapering +
serrulate +  and entire +
toothed +  and 2-fid +
persistent +
redbrown +  and gray-brown +
woolly +  and glabrescent +
flowered +  and pistillate +
subglobose +
0.5 cm5 mm <br />0.005 m <br /> (1.9 cm19 mm <br />0.019 m <br />) +
0.36 cm3.6 mm <br />0.0036 m <br /> (1 cm10 mm <br />0.01 m <br />) +
pendulous +, spreading +  and erect +
Setchell’s willow +
B.C. +, Yukon +  and Alaska. +
10-1100 m +
on proximal 1/2 +, hairy +  and glabrous +
greenish +  and tawny +
0.2 cm2 mm <br />0.002 m <br /> (0.36 cm3.6 mm <br />0.0036 m <br />) +
pistillate +  and staminate +
bisexual +  and unisexual +
spherical +
Pioneer on sandy to gravelly beaches, bars along glacial streams, glacial moraine +
ferruginous +  and white +
cylindrical +, ribbonlike +  and flattened +
unbranched +  and spicate +
subterminal +  and axillary +
membranaceous +
2.5 cm25 mm <br />0.025 m <br /> (8.7 cm87 mm <br />0.087 m <br />) +
obovate +, oblanceolate +, elliptic +  and oblong +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
arranged +  and alternate +
marcescent +
deciduous +
0 cm0 mm <br />0 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
serrulate +  and entire +
connate +  and distinct +
cup-shaped +
2-7[-10]-carpellate +
glabrous +  and not glaucous +
ovoid +  and obclavate +
glandular-dotted +
flat;convex;flat;convex +
Flowering late May-late Jun. +
Univ. Calif. Publ. Bot. +
overlapping +
distinct +
Illustrated +  and Endemic +
branched +, sympodial +, monopodial +  and branching +
semiprostrate;erect +
glabrescent;pubescent +
non-papillate +
cylindrical +
0 cm0 mm <br />0 m <br /> (0.06 cm0.6 mm <br />6.0e-4 m <br />) +
caducous +  and persistent +
distinct +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.04 cm0.4 mm <br />4.0e-4 m <br />) +
persistent +  and deciduous +
ferruginous +  and white +
Salix setchelliana +
Salix sect. Setchellianae +
species +
pointed +
sympodial +, branching +  and heterophyllous +
plant +  and clonal +