General: WARNING: DO NOT TOUCH THIS PLANT! Giant Hogweed is a perennial herb that grows up to 5 metres tall (16 feet). It looks very similar to the native cow parsnip (Heracleum maximum).
Height: Up to 5 meters.
Flowers: It has large umbrella-shaped flower heads that are small white flower clusters.
Leaves/Stems: The stems are hollow with purple spots and the leaves are dark green, resembling a coarsely-toothed maple leaf.
Root: Tuberous root stalks that form new buds each year.
Giant Cow Parsley
Giant Cow Parsnip
Cow Parsnip (Heracleum maximum) - looks similar but is smaller (1 –2 meters tall). Warning: Cow Parsnip also contains a toxic sap that causes severe burns when exposed to sunlight.
Where did it come from? Giant Hogweed was introduced from Asia as an ornamental plant.
Where does it grow here? It flourishes at the coast and in wet places in BC. It prefers rich, wet soils and can tolerate varied amounts of light. Large stands can form in riparian areas and ditchlines.
Reproduction: It spreads by seed and buds from the crown and rootstock. It produces up to 50,000 seeds.
Spreads By: Seed, which can be dispersed by wind or moving contaminated soil.
Plant Type: Perennial.
BC Government. 1996, 2016 edition. Field Guide to Noxious Weeds and other Selected Invasive Plants of British Columbia. Ninth Edition.
Invasive Plant Council of BC. April 2008. Giant Hogweed Targeted Invasive Plant Solutions.
Sea to Sky Invasive Species Council website.
Okanagan Invasive Species Online website.