Parthenium hysterophorus

Parthenium hysterophorus_Ron Vanderhoff
Photo: Ron Vanderhoff

Common names: Santa Maria feverfew

Parthenium hysterophorus (Santa Maria feverfew) is a herb (family Asteraceae) with white flowers and lobed leaves found in the south coast ranges of California. It is native to the American tropics. It favors grasslands and riparian and bottomland habitat. It is a prolific seed producer. Its seeds travel via wind, water, birds, vehicles, farm machinery and other animal traffic.

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

No Weed RIC Management Notes are available for this species. Check for information on other species in the genus on the Weed RIC site.

Cal-IPC Newsletter Articles

There are no newsletter articles associated with this species yet.

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 Parthenium hysterophorus Information

  • CalPhotos - Images of plants taken mostly in California.
  • Calflora - Distribution map and records of this species 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

    Parthenium hysterophorus_flowerhead_RonVanderhoff
    Parthenium hysterophorus (Santa Maria feverfew) flowerhead. Photo: Ron Vanderhoff
    Parthenium hysterophorus_mature fruit_RonVanderhoff
    Parthenium hysterophorus (Santa Maria feverfew) mature fruit. Photo: Ron Vanderhoff
    Parthenium hysterophorus (Santa Maria feverfew) stem. Photo: Ron Vanderhoff
    Parthenium hysterophorus_growth habit_RonVanderhoff
    Parthenium hysterophorus (Santa Maria feverfew) growth habit. Photo: Ron Vanderhoff
    Parthenium hysterophorus_infestation_RonVanderhoff
    Parthenium hysterophorus (Santa Maria feverfew) infestation. Photo: Ron Vanderhoff