Family: Polygonaceae (Dock and Persicaria family).
Native of Europe and south-west Asia.
Occurrence: Widespread. It has a preference for ditches and seasonally wet places. It is an environmental weed.
Clustered Dock is suspected of causing oxalate poisoning in stock, and is a noxious weed in parts of Western Australia.
Similar species: The very common Curled Dock also has rounded fruit with a raised swelling. It is a more robust plant, with denser clusters of flowers, and has larger leaves.