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Salix key for carpellate reproductive material
See list of 30 species in this subkey-
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2a. At least some of the carpellate aments opposite or subopposite
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2b. All carpellate aments alternate
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3a. Floral bracts of aments pale yellow-brown, pale red-brown, or pale green-yellow, sometimes suffused with red near the apex [Fig. 887]
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4a. Ovaries densely white-tomentose, the background color of the ovary nearly or fully concealed by hairs (in part)
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4b. Ovaries moderately sericeous to villous, the background color of the ovary (usually green to light brown) visible through the hairs
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5a. Aments precocious [Fig. 894], 15–37 mm long, borne on flowering branchlets 2.5–7 mm long (in part)
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5b. Aments coetaneous (sometimes also serotinous in S. exigua) [Fig. 888], 16.5–85 mm long, borne on flowering branchlets 1–65 mm long
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6a. Stipes 0.5–0.8 (–1.5) mm long; floral bracts deciduous before maturation of fruit; branchlets of previous year usually glabrous; styles 0–0.2 mm long; aments sometimes branched (in part)
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6b. Stipes (2–) 3–6 mm long; floral bracts persistent in fruit; branchlets of previous year usually pubescent; styles 0.1–0.4 mm long; aments never branched
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7a. Aments precocious (i.e., expanding before the leaves)
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8a. Stipe 0.1–0.5 mm long (up to 0.8 mm long in S. planifolia, an alpine and subalpine species); styles 0.5–2 mm long
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9a. Plants of alpine and subalpine areas, elevation near or exceeding 1000 m
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9b. Plants not of alpine areas, elevation less than 1000 m
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10a. Branchlets glaucous; adaxial nectaries 0.25–1 mm long, shorter than to longer than the stipe; ovules 10–18 per ovary; native plants of northern New England shorelines
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10b. Branchlets not glaucous; adaxial nectaries 0.9–1.4 mm long, longer than the stipe; ovules 18–19 per ovary; non-native plants escaping from cultivation (in part)
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8b. Stipe 0.6–2.7 mm long; styles 0–0.5 (–0.6) mm long (up to 1 mm long in S. discolor)
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11a. Ovaries and capsules short-beaked or blunt at the apex [Fig. 897]; capsules 2.5–4 mm long (in part)
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11b. Ovaries and capsules distally tapering to a distinct beak [Fig. 891]; capsules 5–12 mm long
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12a. Decorticated wood (i.e., with the bark removed) of 1- to 4-year-old branches with many prominent ridges, some longer than 20 mm [Fig. 890]; capsules 5–7 (–8) mm long
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13a. Styles 0.2–0.5 mm long; floral bracts brown to dark brown (at least near the apex)
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13b. Styles 0–0.25 mm long; floral bracts usually light brown to medium red-brown (in part)
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12b. Decorticated wood smooth, with small points, or with a few, short ridges generally shorter than 5 mm; capsules 5–12 mm long
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14a. Stigma lobes 0.2–0.56 mm long; aments 9–47 mm long; styles 0.2–0.4 mm long; floral bracts 0.8–2 mm long
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15a. Carpellate aments (8–) 15–32 mm long, with floral bracts 1.4–1.6 mm long; generally upright shrubs 0.3–3 m tall
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15b. Carpellate aments 10–18 mm long, with floral bracts 0.8–1.4 mm long; decumbent shrubs 0.3–0.7 m tall
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14b. Stigma lobes 0.4–0.72 mm long; aments (25–) 40–108 mm long; styles 0.3–1 mm long; floral bracts 1.4–4 mm long
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16a. Aments (25–) 40–108 mm long; floral scales 1.4–2.5 mm long; styles 0.3–1 mm long
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16b. Aments 27–64 mm long; floral scales 2–4 mm long; styles 0.3–0.6 mm long
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7b. Aments coetaneous or serotinous (i.e., expanding with or after the leaves, respectively)
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17a. Plants 0.03–0.6 (–1) m tall, of alpine areas, elevation exceeding 1000 m
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18a. Aments 11–20.5 mm long; capsules 2–4 mm long; stipes 1–2.2 mm long
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18b. Aments 30–79 mm long; capsules 5–9 mm long; stipes 0.8–1.4 mm long
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17b. Plants 0.3–7 m tall, not of high elevation communities
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19a. Ovary pubescent with bent and crimped, woolly hairs (in part)
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19b. Ovary pubescent with ± straight, silky hairs
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20a. Stipes 0.1–0.5 mm long; styles 0.6–1.8 mm long (in part)
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20b. Stipes 0.6–4 mm long; styles 0–0.5 mm long
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21a. Stipes 1.5–4 mm long; capsules 5–9 mm long; branches flexible, not breaking cleanly at the junction of yearly growth
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21b. Stipes 0.6–1.5 mm long; capsules 2.5–4 mm long; branches brittle at the base and breaking cleanly at the junction of yearly growth (in part)
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1b. Ovaries and capsules glabrous [Fig. 887]
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22a. Floral bracts brown to black (at least at the apex), persisting until after dehiscence of the capsule [Figs. 892,897]
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23a. Dwarf shrubs forming colonies by rhizomes or prostrate stems, rarely exceeding 0.15 m in height, of alpine habitats, elevation exceeding 1000 m; stipes 0.3–1.6 mm long
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24a. Styles 0.35–1 mm long; floral bracts 1.1–1.8 mm long; aments 11–47 mm long
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24b. Styles 0.2–0.4 mm long; floral bracts 0.5–1 mm long; aments 3.2–13 mm long (in part)
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23b. Upright to spreading shrubs, colonial or not, 0.2–6 m tall, not of alpine communities; stipes (1–) 1.2–3.4 mm long
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25a. Floral bracts 0.8–1.6 mm long; styles 0.3–0.6 mm long; stigmas 0.16–0.28 mm wide
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25b. Floral bracts 1.2–3 mm long (mean=1.8 mm); styles (0.3–) 0.5–1.3 mm long; stigmas 0.24–0.56 mm wide
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22b. Floral bracts pale yellow-brown to green-yellow or white-brown, sometimes suffused with red near the apex [Fig. 887], either persisting until after dehiscence of the capsule or deciduous prior to dehiscence the capsule
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26a. Dwarf shrubs 0.01–0.15 m tall, of alpine habitats, elevation exceeding 1000 m; aments 3.2–13 mm long, with 2–11 flowers (in part)
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26b. Short shrubs to trees, 0.3–25 m tall, not of alpine communities; aments 17–80 mm long, with more than 11 flowers
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27a. Aments loosely flowered; flowers ± in whorls about the rachis of the ament
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28a. Stipes 0.5–1.5 mm long; branchlets brittle at base, breaking ± cleanly at the junction of yearly growth; expanding leaf blades green on both surfaces
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28b. Stipes (1–) 1.6–3.2 mm long; branchlets flexible at base, tearing when bent to failure; expanding leaf blades glaucous on the abaxial surface
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27b. Aments densely flowered; flowers spirally arranged about the rachis of the ament
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29a. Emerging leaf blades glaucous abaxially or the surfaces ± concealed by thick tomentum of white to gray hairs
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30a. Floral scales 0.8–1.6 mm long, abaxially very sparsely pubescent with hairs concentrated near apex
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30b. Floral bracts (1–) 1.5–4 mm long, abaxially sparsely to densely pubescent throughout
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31a. Emerging leaf blades membranaceous, translucent; stipes 1.8–3.5 mm long; capsules 7–8 mm long
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31b. Emerging leaf blades thick-membranaceous to herbaceous, opaque or nearly so; stipes 0.2–2.4 mm long; capsules 3–5 mm long (7–12 mm long in S. serissima)
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32a. Emerging leaf blades densely white- to gray-tomentose on the abaxial surface; floral bracts persisting after dehiscence of the capsule
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32b. Emerging leaf blades glabrous or pubescent with straight, silky hairs on the abaxial surface, but then the surface not concealed by the hairs; floral bracts deciduous prior to or during maturation of the capsule
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33a. Aments 11–22 mm thick, 1–2.3 times as long as thick; capsules 7–12 mm long; stipes 1.2–2.4 mm long; native shrub to 5 m tall of fens (in part)
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33b. Aments 4–15 mm thick, 3.9–10.5 times as long as thick; capsules 3.5–5 mm long; stipes 0.2–1.5 mm long; non-native trees to 25 m tall of various habitats, though frequently naturalized in riparian and lakeside forests
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29b. Emerging leaf blades without bloom abaxially (though paler than the adaxial surface), generally pubescent, but the pubescence not dense enough to conceal the surface
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34a. Styles 0–0.2 mm long; aments sometimes branched; expanding leaf blades remotely denticulate (in part)
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34b. Styles 0.3–0.8 mm long; aments unbranched; expanding leaves closely serrulate
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35a. Floral bracts moderately to densely pubescent throughout the abaxial surface; stipes 1.2–2.4 mm long (in part)
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35b. Floral bracts sparsely pubescent, the hairs mainly near the apex; stipes 0.5–1.6 (–2) mm long
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36a. Adaxial nectaries 0.2–0.45 mm long, ⅕ to ⅓ as long as the stipe; abaxial nectaries absent; emerging leaves sometimes with red-brown hairs
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36b. Adaxial nectaries 0.4–0.8 mm long, ½ to fully as long as the stipe; abaxial nectaries present or absent; emerging leaves never with red-brown hairs
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Each photo represents one species in this subkey.