Answer: butterburs

AnswerCrossword Clue
butterbursA Eurasian waterside plant of the daisy family, the rounded flowerheads of which are produced before the leaves. The large soft leaves were formerly used to wrap butter, and extracts of the plant have long been used medicinally as a powerful anticonvulsant
butterbursBUTTERBUR, a plant of damp places with very broad leaves