Giant Hogweed (Heracleum Mantegazzianum)
About Giant Hogweed
Giant Hogweed is a perennial that can grow up to 6 m (19ft) in height and not only does it crowd out native plants it poses a
serious danger to humans. The plants stem hairs and leaves contain a clear, highly toxic sap. When in contact with the skin, it
can cause burns, blisters and scarring, and if it gets in your eyes, it can cause permanent blindness. Giant Hogweed has
numerous small white flower clusters in an umbrella-shaped head, with rigid, hollow green stems covered in dark red or purple
spots. With dark green, coarsely toothed leaves it is a highly competitive plant due to early-season growth, and the seeds
remain viable in the soil for up to 15 years.
How to Remove
- Wear proper clothing. It is very important to cover up before removing Giant Hogweed. WorkSafe BC has issued a Toxic
Plant Warning that requires workers to wear heavy, water-resistant gloves and water-resistant coveralls that completely
covers the skin while handling the plants. Eye protection is highly recommended. Better to seek professional help for
removal and disposal. Report any sightings to the SCRD or local gardening centre.
- Remove lower branches to clear a safe path to the main stem.
- Remove flower heads when main stem is clear to prevent seed growth and dispersal.
- Use a sharp shovel to sever the plant taproot 8 - 12 cm (3in-6in) below the surface of the soil.
- Put the plant (all leaves, stem, and head) in a doubled up strong trash bag for transportation to a proper green waste
disposal facility. DO NOT COMPOST. Disposal facilities: Pender Harbour Transfer Station, Sechelt Landfill.
- Alternative plants: Blue Elderberry, Ligularia, Rodgersia, Wild Celery.