Giant hogweed (Heracleum mantegazzianum) is an exotic weed in Illinois. The Illinois Exotic Weed Act prohibits the sale or distribution of this plant in Illinois. This plant spreads by seed. It commonly grows in wetlands and disturbed areas. Giant hogweed was introduced from Asia as an ornamental plant, but today is found in the Midwest, Northeast, and parts of the Pacific Coast.
Giant hogweed is a dangerous plant. It is dangerous to handle, as its sap contains toxins. In sunlight, the sap can cause severe rashes or burns when contact is made with skin. This plant is also known to outcompete the native plants for resources and space. After they die back in the winter, a swift reduction in the population of the large plants leads to soil erosion and habitat destruction.
As a good alternative, common boneset (Eutrochium perfoliatum) can be planted instead for its similar inflorescence and growth habit. There are a number of native and non-native species that could be used in place of giant hogweed. More desirable species may be found using the online Search Trees and Plants page of the Arboretum website. Before purchasing or planting, be sure to check for any local or state guidelines on this species, and ensure that this plant is suitable for its habitat by checking its attributes at mortonarb.org or plants.usda.gov.
- Family (English) Parsley
- Family (botanic) Apiaceae
- Hardiness zones Zone 4, Zone 5 (Northern Illinois), Zone 6 (City of Chicago), Zone 7, Zone 8