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Packera
See list of 4 species in this genusPackera plattensis (Nutt.) W.A. Weber & A. Löve, a species primarily of the Midwest, Great Lakes region, and southern states, continues to be reported from New England (Magee and Ahles 1999). However, the plants responsible for this report were carefully examined and found to be P. paupercula (Barkley 1962). References: Barkley (1962), Trock (2006).
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1a. Plants with stolons and shallow rhizomes, forming colonies; leaf blades decurrent on petioles for some distance; involucral bracts abruptly tapering to an acuminate apex from above the middle
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1b. Plants without stolons, or these short and poorly developed, not forming colonies; leaf blades not or very shortly decurrent on petioles; involucral bracts gradually tapering from base or with parallel margins and gradually tapering from near apex
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2a. Basal leaf blades tapering to petiole, usually cuneate at the base; plants of gravels, ledges, and balds
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2b. Blade of basal leaves abruptly contracted to the petiole, usually truncate to cordate at the base [Fig. 441]; plants of wet-mesic to hydric soils of fields, low forests, and wetlands
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3a. Blade of basal leaves usually 1.75–3.5 times as long as wide, sharply and finely toothed, rounded to subcordate at the base, acute to obtuse at the apex [Fig. 441]
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3b. Blade of basal leaves usually 0.75–1.5 (–1.75) times as long as wide, crenate, strongly cordate at the base, rounded at the apex
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Each photo represents one species in this genus.