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Taxon  Report  
Horkelia tenuiloba  (Torr.) A. Gray
Santa rosa horkelia,   Thin lobed horkelia
Horkelia tenuiloba is a perennial herb that is native to California, and endemic (limited) to California.
California Rare Plant Rank: 1B.2 (rare, threatened, or endangered in CA and elsewhere).
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
~85 records in California
yellowone or more occurrences
within a 7.5-minute quadrangle

Bloom Period
Genus: Horkelia
Family: Rosaceae  
Category: angiosperm  
PLANTS group:Dicot
Jepson eFlora section: eudicot

Habitat: openings

Communities: Chaparral

Name Status:
Accepted by JEF + CNPS + PLANTS

Alternate Names:
PLANTSPotentilla micheneri
Information about  Horkelia tenuiloba from other sources
Nursery availability from CNPLX
This plant is available commercially.
Jepson eFlora


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[Wikipedia] Range, Description, Threats: Horkelia tenuiloba is a species of flowering plant in the rose family known by the common names Santa Rosa oceanspray,[1] Santa Rosa horkelia and thin-lobed horkelia. It is endemic to California, where it is known only from the coastal hills and mountains north of the San Francisco Bay Area. It is a plant of chaparral habitat.[1] This is a perennial herb producing a low mat of hairy, glandular green foliage around a woody base. The leaves are cylindrical or somewhat flat, often tapering to a point, and each is made up of several densely packed pairs of hairy leaflets. The inflorescence is an array of flowers atop an erect stalk, each flower made up of five pointed green sepals and five white petals. At the center of the flower is a cone of stamens tipped with reddish anthers around many pistils. It flowers in May.[2][better source needed] It is threatened by trampling, trail maintenance, and development.[1] (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: 04/12/2024).