Adiantum

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  A. pedatum

  1a. Ultimate segments of leaves ± oblong, rounded to obtuse at the apex [Fig. 32], in the same plane with the axis of the blade, thin-herbaceous to herbaceous, bright green to yellow-green; leaf blades lax and arching; plants primarily of rich, mesic forests
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  1b. Ultimate segments of leaves ± triangular, acute to obtuse at the apex [Fig. 33], twisted out of the plane of the axis of the blade (but usually in plane with the blade axis in shaded plants), firm-herbaceous to chartaceous, medium green to blue-green (often bright green 
in the shade); leaf blades usually stiff and upright (lax in shaded plants); plants of serpentine rocks and soil
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    A. aleuticum

    2a. Medial ultimate segments of leaves on stalks 0.3–1.3 mm long, most stalks shorter than 0.9 mm; false indusia 0.8–2.9 (–3.4) mm long; rhizomes frequently branching and congested, with internodes 1–2 mm long
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    A. viridimontanum

    2b. Medial ultimate segments of leaves on stalks (0.4–) 0.6–1.5 (–1.9) mm long, most stalks longer than 0.9 mm; false indusia 2–5 (–10) mm long; rhizomes occasionally branching (rarely congested), with internodes 4–7.5 mm long

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 Show photos of:   Each photo represents one species in this genus.