Heracleum mantegazzianum

Heracleum mantegazzianum_Fritz Geller-Grimm Wikimedia
Photo: Fritz Geller-Grimm

Common names: giant hogweed

Heracleum mantegazzianum (giant hogweed) is a herb/ (family Apiaceae) with white flowers and large toothed leaves found in the northwestern ranges of Oregon. It is native to central Asia. It favors grasslands and riparian and bottomland habitat. It reproduces only by seed. Seeds fall within 13 feet of the parent plant and can be carried by water and wind. Sticky seeds attach on to humans, animals and machinery.

Cal-IPC Rating: Watch

CDFA Rating: A?


Plant Risk Assessment - An evaluation of the potential for a plant to be invasive in California.

Weed Management Notes

  • Management Notes - Information on management techniques and effectiveness from the University of California Cooperative Extension’s Weed Research & Information Center.

Cal-IPC Newsletter Articles

Cal-IPC Symposium Presentations

Presentations are linked where available. Where a presentation is not available, find more information by reading the abstract in the Cal-IPC Symposia Archive.

Other Heracleum mantegazzianum Information

  • CalPhotos - Images of plants taken mostly in California.
  • CalWeedMapper - Distribution map of this species in California with ability to determine regional priorities.
  • EDDMapS - Distribution of this species in North America.
  • USDA PLANTS Database - Information on identification and distribution, with links to websites in individual states.
  • Additional photos

    Heracleum mantegazzianum_flowers_BillMoses
    Heracleum mantegazzianum (giant hogweed) flowers. Photo: Bill Moses
    Heracleum mantegazzianum_growth habit_BillMoses
    Heracleum mantegazzianum (giant hogweed) growth habit. Photo: Bill Moses
    Heracleum mantegazzianum_seed_BillMoses
    Heracleum mantegazzianum (giant hogweed) seed. Photo: Bill Moses