| 1 |
Branchlets pendulous. |
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(2) |
| + |
Branchlets erect or spreading, not pendulous (except sometimes in S. matsudana). |
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(3) |
| |
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| 2 (1) |
Leaf base cuneate; ovary glabrous or pilose at base |
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36 Salix babylonica |
| + |
Leaf base narrowly cuneate; ovary downy proximally |
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37 Salix pseudolasiogyne |
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| 3 (1) |
Branchlets brownish green, relatively stout, brittle; leaves adaxially dull green, pubescent along midvein, abaxially glaucous, glabrous |
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28 Salix fragilis |
| + |
Branchlets not brownish green; leaves not as above. |
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(4) |
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| 4 (3) |
Young branchlets tomentose; young leaves silvery sericeous, rarely subglabrescent |
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27 Salix alba |
| + |
Young branchlets glabrous or pilose, not tomentose; young leaves glabrous or pilose, not silvery sericeous (except abaxially in S. chienii). |
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(5) |
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| 5 (4) |
Leaf margin indistinctly serrate or entire |
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47 Salix longistamina |
| + |
Leaf margin serrulate, rarely subentire. |
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(6) |
| |
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| 6 (5) |
Leaves abaxially greenish or with a bluish green tinge. |
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(7) |
| + |
Leaves abaxially glaucous or slightly white. |
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(11) |
| |
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| 7 (6) |
Leaf blade broadest at or above middle. |
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(8) |
| + |
Leaf blade broadest below middle, lanceolate or narrowly lanceolate. |
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(9) |
| |
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| 8 (7) |
Leaf blade oblanceolate or oblong-lanceolate |
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40 Salix eriocarpa |
| + |
Leaf blade elliptic, obovate, lanceolate, or obovate-lanceolate |
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30 Salix jishiensis |
| |
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| 9 (7) |
Young leaves pilose, when mature 5-7 cm; stipules semicordate, ca. 5 mm |
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26 Salix heteromera |
| + |
Young leaves densely downy, when mature 3-5 cm; stipules small or absent, less than 3 mm. |
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(10) |
| |
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| 10 (9) |
Branchlets reddish brown or purplish brown; petiole 1.5-5 mm |
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34 Salix sphaeronymphoides |
| + |
Branchlets yellowish brown; petiole ca. 7 mm |
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43 Salix bangongensis |
| |
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| 11 (6) |
Leaves 2-3.5 cm, abaxially sericeous (rarely subglabrous); petiole ca. 1 mm |
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35 Salix chienii |
| + |
Leaves more than 3.5 cm, abaxially glabrous or pilose, not sericeous; petiole more than 1.5 mm. |
|
(12) |
| |
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| 12 (11) |
Leaf apex long acuminate, becoming awned |
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33 Salix pingliensis |
| + |
Leaf apex acute, shortly to long acuminate, not becoming awned. |
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(13) |
| |
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| 13 (12) |
Leaf blade 2.3-5 cm wide, margin coarsely serrate; stipules semicordate, 3-5 mm |
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31 Salix weixiensis |
| + |
Leaf blade less than 2 cm wide, margin serrulate; stipules small or absent. |
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(14) |
| |
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| 14 (13) |
Young branchlets slightly pilose or subglabrous |
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34 Salix sphaeronymphoides |
| + |
Young branchlets pilose. |
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(15) |
| |
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| 15 (14) |
Leaf blade ca. 3 × as long as wide (3.5-6 × 1.2-1.6 cm). |
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(16) |
| + |
Leaves more than 3 × as long as wide. |
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(17) |
| |
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| 16 (15) |
Leaf apex shortly acuminate or acuminate, base rounded-cuneate; petiole 2-3 mm |
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39 Salix bikouensis |
| + |
Leaf apex acute, base subrounded or rounded-cuneate; petiole 4-7 mm |
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42 Salix qinghaiensis |
| |
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| 17 (15) |
Leaf blade more than 5 × as long as wide. |
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(18) |
| + |
Leaf blade less than 5 × as long as wide. |
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(20) |
| |
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| 18 (17) |
Petiole 2-4 mm |
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38 Salix capitata |
| + |
Petiole more than 4 mm. |
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(19) |
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| 19 (18) |
Leaf blade acuminate at apex, abaxially pale, densely downy along midvein |
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41 Salix koreensis |
| + |
Leaf blade long acuminate at apex, abaxially slightly white; subglabrous along midvein |
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32 Salix matsudana |
| |
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| 20 (17) |
Leaf blade shortly acuminate or acute (rarely acuminate) at apex, abaxially densely sericeous when young (or glabrous when mature); petiole ca. 8 mm |
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29 Salix chikungensis |
| + |
Leaf blade acuminate or long acuminate at apex, abaxially pilose when young, not sericeous; petiole less than 5 mm. |
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(21) |
| |
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| 21 (20) |
Leaf blade 8-12 × 2-3 cm, apex long acuminate; branchlets grayish green or grayish yellow |
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46 Salix pierotii |
| + |
Leaf blade 5-8 × 1.2-1.8 cm, apex acuminate; branchlets purplish brown or brown |
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45 Salix sericocarpa |
