|MadSci Network: Botany|
Echinacea is not toxic but I would not consider it a food plant and would not advise eating it. Its use is medicinal and all parts of the plants are used. The dried root has been widely used by either ingesting it in powdered form or by drinking a decoction. Some people swear by this plant and others say that it is hype. (see Joe Paxton's answer)
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