Includes the buckwheats

• A family of plants of order Polygonales chiefly of the north temperate zone

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The Polygonaceae are a family of flowering plants known informally as the knotweed family or smartweed—buckwheat family in the United States. The name is based on the genus Polygonum , and was first used by Antoine Laurent de Jussieu in 1789 in his book, ...