Also called wood poppy.  In North America, do not confuse with very-similar-named (and very-similar-looking!) greater celandine poppy  Chelidonium majus.   Although members of separate genera, both are part of poppy  family Papaveraceae.

And do not confuse either with very-similar-named lesser celandine  Ficaria verna.   Although together the three species are members of two separate families, all three are part of barberry/​buttercup/​poppy  order Ranunculales.

Native to central and eastern 🇨🇦 Canada and 🇺🇸 USA.

Uses by native peoples
(Ethnobotany database)

Learn more about celandine poppy Stylophorum diphyllum

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