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Taxon  Report  
Parthenium hysterophorus  L.
Santa maria feverfew
Parthenium hysterophorus is a perennial herb that is not native to California.
There is a high risk of this plant becoming invasive in California according to Cal-IPC.
Siskiyou Del Norte Modoc Humboldt Shasta Lassen Trinity Plumas Tehama Butte Mendocino Glenn Sierra Yuba Lake Nevada Colusa Placer Sutter El Dorado Yolo Alpine Napa Sonoma Sacramento Mono Amador Solano Calaveras Tuolumne San Joaquin Marin Contra Costa Alameda Santa Cruz Mariposa Madera San Francisco San Mateo Merced Fresno Stanislaus Santa Clara Inyo San Benito Tulare Kings Monterey San Bernardino San Luis Obispo Kern Santa Barbara Ventura Los Angeles Riverside Orange San Diego Imperial
Observation Search
~69 records in California
redone or more occurrences
within a 7.5-minute quadrangle
Genus: Parthenium
Family: Asteraceae  
Category: angiosperm  
PLANTS group:Dicot
Jepson eFlora section: eudicot

Name Status:
Accepted by JEF + PLANTS

Alternate Names:
PLANTSParthenium lobatum
Information about  Parthenium hysterophorus from other sources

[Wikipedia] American Tropics native, Invasive: Parthenium hysterophorus is a species of flowering plant in the family Asteraceae. It is native to the American tropics.[1] Common names include Santa-Maria,[2] Santa Maria feverfew,[3] whitetop weed,[4] and famine weed.[5] In India, it is locally known as carrot grass, congress grass or Gajar Ghas or Dhanura.[6] It is a common invasive species[7] in India,[8] Australia, and parts of Africa.[5] Invasive species Parthenium hysterophorus invades disturbed land, including roadsides. It infests pastures and farmland, causing often disastrous loss of yield, as reflected in common names such as famine weed.[9][10][11][12][13] In some areas, heavy outbreaks have been ubiquitous, affecting livestock and crop production, and human health (contributed by Mary Ann Machi)


Suggested Citation
Calflora: Information on California plants for education, research and conservation, with data contributed by public and private institutions and individuals. [web application]. 2024. Berkeley, California: The Calflora Database [a non-profit organization]. Available: https://www.calflora.org/   (Accessed: 04/19/2024).