Knotweed is a common name for plants in several genera in the family

Polygonaceae The Polygonaceae are a Family (biology), family of flowering plants known Common name, informally as the knotweed family or smartweed—buckwheat family in the United States. The Botanical name, name is Basionym, based on the genus ''Polygonum'', ...

. Knotweed may refer to: * ''

Fallopia ''Fallopia'' is a genus of about 12 species of flowering plants in the buckwheat family, often included in a wider treatment of the related genus ''Polygonum'' in the past, and previously including ''Reynoutria''. The genus is native to temperat ...

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Persicaria ''Persicaria'' is a genus of herbaceous flowering plants in the knotweed family, Polygonaceae. Plants of the genus are known commonly as knotweeds or smartweeds.Polygonum ''Polygonum'' is a genus of about 130 species of flowering plants in the buckwheat and knotweed family Polygonaceae. Common names include knotweed and knotgrass (though the common names may refer more broadly to plants from Polygonaceae). In the ...

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Reynoutria ''Reynoutria'' is a genus of flowering plants in the Polygonaceae, also known as the knotweed or buckwheat family. The genus is native to eastern China, Eastern Asia and the Russian Far East, although species have been introduced to Europe and No ...

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Reynoutria japonica ''Reynoutria japonica'', synonyms ''Fallopia japonica'' and ''Polygonum cuspidatum'', is a species of herbaceous perennial plant in the knotweed and buckwheat family Polygonaceae. Common names include Japanese knotweed and Asian knotweed. It is ...

'' or Japanese knotweed, a highly invasive species in Europe and North America

See also