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Taxon  Report  
Cephalanthus occidentalis  L.
Common buttonbush
Cephalanthus occidentalis is a shrub that is native to California, and also found elsewhere in western North America.
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
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Bloom Period
Genus: Cephalanthus
Family: Rubiaceae  
Category: angiosperm  
PLANTS group:Dicot
Jepson eFlora section: eudicot

Toxicity: Do not eat the leaf of this plant.

Wetlands: Occurs in wetlands

Habitat: streambanks

Communities: Mixed Evergreen Forest, Foothill Woodland, Valley Grassland, wetland-riparian

Name Status:
Accepted by JEF + PLANTS

Alternate Names:
PLANTSCephalanthus occidentalis var. californicus
PLANTSCephalanthus occidentalis var. pubescens
Information about  Cephalanthus occidentalis from other sources
Nursery availability from CNPLX
This plant is available commercially.
Jepson eFlora

USDA PLANTS Profile (CEOC2)

Photos on Calflora

Photos on CalPhotos

Google Images

Photos on iNaturalist

ID Tips on PlantID.net

[Wikipedia] Description, Taxonomy, Ecology, Uses: Taxonomy There are two varieties, not considered distinct by all authorities: Cephalanthus occidentalis var. occidentalis (syn. var. pubescens) common buttonbush. Eastern North America from Nova Scotia west to Minnesota and south to Florida and east Texas. Cephalanthus occidentalis var. californicus California button-willow. Southwestern North America, from west Texas west to California (Sierra Nevada foothills, San Joaquin Valley, Sacramento Valley, and the Inner North Coast Ranges) and south to Mexico and Central America. Ecology Waterfowl and other birds eat the seeds. Wood ducks utilize the plant as nest protection, and mallards eat the fruit.[6] Deer browse the foliage, which is poisonous to livestock.[7] Insects and hummingbirds take the nectar, with bees using it to make honey.[5][8] It is a larval host to the hydrangea sphinx, the royal walnut moth, and the titan sphinx.[9] Uses Medicinal Cephalanthus occidentalis has a number of historical medicinal uses, but it is also toxic due to the presence of cephalanthin.[5][8] (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: 04/13/2024).