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Key to Erigeron, Key A: Key to "conyzoid" Erigeron

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1 Plants diffusely branched from the base and throughout; plants 1-2.5 (-3) dm tall
1 Plants with a well-developed central axis, sparingly branched (unless on coastal dunes, mowed, or otherwise injured); plants 1-15 dm tall.
..2 Involucre 4-6 mm high, densely pubescent; pistillate flowers 20-150 (or more) per head.
....3 Cauline leaves characteristically linear to linear-oblanceolate; capitulescence corymbiform to racemiform, less commonly thyrsoid; fruiting receptacles (2-) 2.5-4 (-5) mm wide, not alveolate or sometimes the inner florets barely so; phyllaries linear-lanceolate, relatively thick and opaque, 0.3-0.5 mm wide, green to greenish brown with a narrow, orange-resinous midvein, hispid-hirsute with thick-based hairs, sometimes purple-tipped, inserted on a ring of fused tissue; pistillate florets ca. 40-150, in (2-) 3-6 series
....3 Cauline leaves characteristically narrowly lanceolate-elliptic to lanceolate or oblanceolate; capitulescence usually paniculate-thyrsoid; fruiting receptacles 1.5-2.5 mm wide, weakly but distinctly alveolate (lens), outer to inner florets; phyllaries narrowly ovate, relatively thin and translucent, 0.5-0.8 mm wide, central part yellow-brown with an inconspicuous midvein, loosely strigose with thin-based hairs, never purple-tipped, inserted at apex of peduncle; pistillate florets ca. 20-50, in 2-3 series
..2 Involucre 3-4 mm high, glabrous or very sparsely pubescent; pistillate flowers mostly 25-45 per head.
......4 Stem coarsely spreading-hirsute; leaves ciliate, the larger generally with a few to many coarse teeth; phyllaries green-tipped or white-tipped
......4 Stem glabrous or with widely scattered, appressed hairs; leaves with a few cilia toward the base, generally entire; phyllaries purple-tipped
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