The River Annan Trust & District Salmon Fishery Board

Giant Hogweed (Heracleum mantegazzianum)

Easy to identify when fully grown by its height, size of leaves and size of flowers. Its spreads solely by seeds and is capable of producing up to 50,000 of them. Seeds can remain viable for up to 15 years.

Key ID Features

White flowers up to 500mm across - in a large umbrella like flower (June - July)

Heracleum mantegazzianum
Heracleum mantegazzianum

Green stems with dark-red or purple blotches

Contact Us


Fisheries Office
Annandale Estates, St Ann's
Tel: 01576 470600

Mobile: 07710331079

Image: RPS group Plc

Stems often with sharp brissles

Heracleum mantegazzianum

Image: RPS group Plc

Report an Invasive Species


Tel: 01576 470600



Heracleum mantegazzianum

Can grow up to 5 metres tall

Lower leaves can be up to 1.5 metres long & grow in a rosette

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Leaves are dark gren with a jagged appearance and spiky at the ends

Bristles on underside

Image: RPS group Plc

Do's & Don'ts

Best Methods of Control

  • Never throw away or fly tip plant material or soil –  under the Wildlife and Countryside Act 1981, it is an offence “to plant or otherwise encourage in the wild” the growth of giant hogweed
  •  Giant hogweed should not be touched without protective clothing as contact with the sap can produce a painful skin condition.
  • Scottish Environment Protection Agency (SEPA) must be contacted before using chemicals in or near water.
  •  Be careful not to transport seeds to new sites
  •  Removal of plant material off site must be undertaken by a licenced carrier
  •  Report giant hogweed to