Polygonaceae
Cape knotweed
Polygonum undulatum
- Family
- Polygonaceae
- Genus
- Polygonum
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Common names
By language (1)
- English
- Cape knotweed
Synonyms
- Polygonum atraphaxis Thunb.
- Polygonum atraphaxoides Thunb.
Photos
Photo: SAplants, CC BY-SA 4.0, from Wikimedia Commons 
Photo: SAplants, CC BY-SA 4.0, from Wikimedia Commons 
Photo: SAplants, CC BY-SA 4.0, from Wikimedia Commons 
Photo: SAplants, CC BY-SA 4.0, from Wikimedia Commons 
Photo: SAplants, CC BY-SA 4.0, from Wikimedia Commons
More in Polygonum
- Yard knotweedPolygonum avicularePolygonaceae
- Oval-leaf knotweedPolygonum arenastrumPolygonaceae
- Polygonum maritimumPolygonaceae
- Asiatic tearthumbPolygonum perfoliatumPolygonaceae
- Bellard's smartweedPolygonum patulumPolygonaceae
- European knotweedPolygonum arenariumPolygonaceae
- Narrowleaf knotweedPolygonum bellardiiPolygonaceae
- Polygonum cognatumPolygonaceae
- Horse-tail knotweedPolygonum equisetiformePolygonaceae
- KnotweedPolygonum oxyspermumPolygonaceae
- Douglas' knotweedPolygonum douglasiiPolygonaceae
- Erect knotweedPolygonum erectumPolygonaceae
Sources: classification, synonyms from World Flora Online Plant List (2026-06, CC0 1.0); common names, popularity from Wikidata (2026-10-26, CC0 1.0). About our plant data.