Sorbus sitchensis

M. Roemer

Fam. Nat. Syn. Monogr. 3: 139. 1847.

Endemic
Treatment appears in FNA Volume 9. Treatment on page 444. Mentioned on page 436, 442.

Shrubs, 10–40 dm. Stems 1–8; bark initially reddish purple to brownish gray, becoming grayish red; winter buds red-purple to redbrown, conic to ovoid, 8–13 mm, dull, slightly glaucous, not glutinous, sparsely or densely villous, hairs primarily rufous. Leaves pinnately compound; stipules persistent, sometimes deciduous, hairs rufous; blade paler abaxially, dull blue-green, usually slightly glaucous, rarely faintly shiny adaxially, leaflets 7–13, opposite, sometimes subopposite, oblong to narrowly elliptic, sometimes oblanceolate, ovate, or obovate, 1.8–6 × 0.6–2.5 cm, l/w ratio 1.9–3.5, margins entire or finely to coarsely serrate, sometimes doubly serrate, apex obtuse or acute, surfaces soon glabrous, leaf and leaflet axils hairy, hairs rufous. Panicles 12–80-flowered, rounded, 2–8 cm diam.; peduncles glabrous, glaucous, or sparsely to densely villous, hairs primarily rufous. Pedicels glabrous, glaucous, or sparsely to densely villous, hairs primarily rufous. Flowers 11–17 mm diam.; hypanthium glabrous, glaucous, hypanthium plus sepals 3–4 mm; sepals 1–2.2 mm, margins lightly to moderately ciliate, hairs rufous or whitish, infrequently glandular; petals white, rarely pinkish, rhombic to ovate, 4–7.5 mm; stamens 15–20; carpels distinct, apex concave, depressed, or slightly conic and truncate, styles 3–5, 1.5–3.2 mm. Infructescences glabrous, glaucous, or villous. Pomes pinkish red or red (often appearing slightly purplish), subglobose to broadly elliptic or obovoid, 7–13 × 7–13 mm, dull, glaucous; sepals inconspicuous, incurved. Seeds redbrown, ovoid to ovoid-lanceolate, oblong or elliptic, 3.4–5 × 2.2–2.9 mm, symmetric or trigonous, slightly flattened.

Distribution

V9 748-distribution-map.jpg

Alta., B.C., Yukon, Alaska, Calif., Idaho, Mont., Oreg., Wash.

Discussion

Varieties 2 (2 in the flora).

The other western Sorbus with rufous indument in the leaf and leaflet axils is S. californica, which differs in its smaller, shinier leaflets, less hairy inflorescences, and shiny winter buds. The winter buds of S. sitchensis are hairier and less scaly at the summit, also glaucous and never shiny or glutinous. In the field, the fresh fruits of S. sitchensis are often pinkish red; fruits of S. californica and S. scopulina are generally orange-red.

Selected References

None.

Key

1 Leaflet margins toothed apically, serrate for more than 1/2 their length; petals white. Sorbus sitchensis var. sitchensis
1 Leaflet margins entire or toothed apically, serrate for less than 1/2 their length; petals white or pinkish. Sorbus sitchensis var. grayi
... more about "Sorbus sitchensis"
Peter F. Zika +  and Stéphane M. Bailleul +
M. Roemer +
grayish red +, initially reddish purple +  and brownish gray +
compound +  and simple +
opposite +  and alternate +
not +  and clawed +
Sorbus ser. +
blue-green +  and paler +
shiny +  and dull +
ovate +  and oblong +
5 cm50 mm <br />0.05 m <br /> (33 cm330 mm <br />0.33 m <br />) +
? (?) +  and ? (?) +
not glutinous +
red-purple +  and redbrown +
villous +  and glaucous +
0.8 cm8 mm <br />0.008 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
odd +  and simple +
divided +  and lobed +
tanniferous +
Alta. +, B.C. +, Yukon +, Alaska +, Calif. +, Idaho +, Mont. +, Oreg. +  and Wash. +
not +  and aggregated +
single-layered +
1.1 cm11 mm <br />0.011 m <br /> (1.7 cm17 mm <br />0.017 m <br />) +
rancid +, unpleasant +  and strong +
unisexual +  and bisexual +
not +  and aggregated +
not +  and aggregated +
yellow +, brown +, red +  and orange +
glabrous +, hairy +  and glaucous +
0.4 cm4 mm <br />0.004 m <br /> (1.9 cm19 mm <br />0.019 m <br />) +
whitish +  and rufous +
green +  and red +
glaucous +  and glabrous +
0.2 cm2 mm <br />0.002 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
villous +, glaucous +  and glabrous +
crassinucellate +
deciduous +
subopposite +  and opposite +
0.6 cm6 mm <br />0.006 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
papillose +
obovate +, ovate +, oblanceolate +, oblong +  and narrowly elliptic +
serrate +, entire or +  and finely coarsely serrate +
toothed +, unlobed +  and lobed +
inferior +  and superior +
biseriate +  and clustered +
collateral +  and basal +
3 +  and 2 +
12-80-flowered +
2 cm20 mm <br />0.02 m <br /> (8 cm80 mm <br />0.08 m <br />) +
hairy +, glaucous +  and glabrous +
glaucous or +  and sparsely densely villous +
glaucous or +  and sparsely densely villous +
0 (?) +  and 4 (?) +
free +  and distinct +
2 +  and 5 +
0.4 cm4 mm <br />0.004 m <br /> (0.75 cm7.5 mm <br />0.0075 m <br />) +
adnate +, free +, connate +  and distinct +
red +  and pinkish red +
0.7 cm7 mm <br />0.007 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
subglobose +  and broadly elliptic or obovoid +
0.7 cm7 mm <br />0.007 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
Fam. Nat. Syn. Monogr. +
not arillate +
0.34 cm3.4 mm <br />0.0034 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
flattened;trigonous;symmetric;ovoid;ovoid-lanceolate oblong or elliptic +
0.22 cm2.2 mm <br />0.0022 m <br /> (?) +  and 0.29 cm2.9 mm <br />0.0029 m <br /> (?) +
persistent +
free +  and distinct +
inconspicuous +
triangular +  and ovate +
0.1 cm1 mm <br />0.001 m <br /> (0.22 cm2.2 mm <br />0.0022 m <br />) +
free +  and distinct +
branched +  and simple +
ascending +  and erect +
1 +  and 8 +
deciduous +  and persistent +
short-adnate +  and free +
persistent +
distinct +
basal +, lateral +, subterminal +  and terminal +
elongate +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.32 cm3.2 mm <br />0.0032 m <br />) +
Sorbus sitchensis +
Sorbus sect. Tianshanicae +
species +
inconspicuous +
hairy +  and glabrous +