What is Giant Hogweed?

Giant Hogweed (Herocleum Mantegazziamum), is a non-native, invasive plant that was originally imported into the UK as an ornamental garden plant.  It now grows in the wild, mainly along riverbanks, canals, footpaths and roads.

How to identify?

  • Tall bamboo like stems that grow up to 5 metres tall
  • Stems have sharp bristle and are green with purple blotches
  • Leaves grow up to 3 metres in length, are serrated and have bristles underneath
  • White umbrella shaped flower heads up to 80cm in diameter

What are the dangers?

  • Giant Hogweed is Phototoxic, meaning that it produces a toxic sap that is activated by sunlight
  • Contact of the sap with human skin causes Phytophotodermatitis also known as Giant Hogweed burns
  • These burns blister, leaving scars on the skin
  • If the sap comes into contact with the eyes, then blindness can occur
  • The symptoms can re-occur year after year, activated when the skin is under direct sunlight

What to do if you get burnt?

  • If you think you have been in contact with sap you should cover the affected area immediately to protect it from sunlight
  • Wash the area thoroughly with soap and water
  • Seek medical advice regarding anti histamines or creams
  • Do not burst blisters

How do I remove it?

Removal needs to be carried out by a competent contractor.  Not only does the correct Personal Protective Equipment need to be worn, a waste carriers licence is required to dispose of it.  A herbicide treatment can be applied when it is in early growth stage.  Alternatively it can be removed if is in flower or causing a Health and Safety issue.