Trying to identify these, but having no luck. 3-4' tall growing in very wet...
It looks like you have curly dock, Rumex crispus, an introduced plant from Eurasia and state-listed secondary noxious weed in Minnesota. It occurs in a variety of habitats but is most common in wetland areas or disturbed areas. It "usually" does not persist once other competitive vegetation gets established but the can re-invade if favorable conditions exist.
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