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Giant Hogweed

Giant Hogweed (Heracleum mantegazzianum) is a large member of the carrot family, brought in as an ornamental plant from its native range in south eastern Europe.  It is generally found near watercourses and in damp meadows, though it can be found on waste ground. It is highly invasive and non native.  Each plant can produce up to 50,000 seeds which can survive for up to 15 years.  

Contact with the cut material in sunlight produces a skin reaction in almost all cases. Blisters occur 24 to 48 hours after exposure, and dense pigmentation is visible after three to five days. Damaged skin will heal very slowly; leaving residual pigmentation that can develop into phytophotodermatitis - a type of dermatitis that flares up in sunlight and for which there is no straightforward treatment. Cut stems and leaves remain active for several hours.

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Giant Hogweed is capable of growing to a height of up to 5 metres (15 feet) and should not be confused with our native common hogweed (Heracleum sphondylium) which is much smaller (generally less than 2m tall), common, widespread and causes few problems.

You can find out more about Giant Hogweed including

  • what it looks like 
  • what you should do if you see it and how it can be treated
  • who to contact if you need more guidance or see hogweed growing on other property
  • what our native common hogweed (Heracleum sphondylium) looks like

by downloading the Giant hogweed - guidance and control leaflet.