Pictorial guide to the flora of the British Isles

Home ⟩ Pictorial Guide ⟩ Apiaceae / Umbelliferae ⟩ Heracleum mantegazzianum / giant hogweed

Heracleum mantegazzianum Sommier & Levier

giant hogweed (Apiaceae / Umbelliferae)

 SpreadBias within British IslesDirection of bias
Very widespreadNegligible tendencyE
Plant Atlas 2020
BSBI Distribution Map

Heracleum mantegazzianum is an exceptionally large herb; it is considered invasive, and may not be planted in the wild in the United Kingdom, under Schedule 9 of the Wildlife and Countryside Act 1981.

Great Haseley (VC23: Oxfordshire); 2015-06-17

 giant hogweed / Heracleum mantegazzianum: _Heracleum mantegazzianum_ is an exceptionally large herb; it is considered invasive, and may not be planted in the wild in the United Kingdom, under <a href="sched9.html">Schedule 9</a> of the Wildlife and Countryside Act 1981.

The central umbel of the inflorescence of Heracleum mantegazzianum may be up to 40 cm (16”) across.

Great Haseley (VC23: Oxfordshire); 2015-06-17

 giant hogweed / Heracleum mantegazzianum: The central umbel of the inflorescence of _Heracleum mantegazzianum_ may be up to 40 cm (16”) across.

The sap of Heracleum mantegazzianum is phototoxic, and can cause blistering if it touches skin that is later exposed to UV light.

Great Haseley (VC23: Oxfordshire); 2015-06-17

 giant hogweed / Heracleum mantegazzianum: The sap of _Heracleum mantegazzianum_ is phototoxic, and can cause blistering if it touches skin that is later exposed to UV light.

All images copyright © Christopher J. Dixon unless otherwise indicated.

L-R: Bidens tripartita, Melilotus officinalis, Mimulus guttatus, Thalictrum flavum, Ranunculus peltatus, Anchusa arvensis, Malva alcea, Lolium perenne