Taxon Report
Clarkia speciosa Lewis & Lewis ssp. immaculata Lewis & LewisPismo clarkia |
 Aaron Schusteff |
Taxon Summary
Clarkia speciosa ssp. immaculata, commonly known as Pismo clarkia, is a annual herb in the Onagraceae that is found only in California. It occurs within Chaparral (margins, openings), Cismontane woodland, and Valley and foothill grassland, growing at elevations from 25 to 185 meters. Clarkia speciosa ssp. immaculata is ranked 1B.1, Plants Rare, Threatened or Endangered in California and Elsewhere; Seriously threatened in California.Classification
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Scientific Name: |
Clarkia speciosa Lewis & Lewis ssp. immaculata Lewis & Lewis |
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Common Name: |
Pismo clarkia |
| Family: | Onagraceae |
| Element Code: | PDONA05111 |
| USDA Plants Symbol: | CLSPI |
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Synonyms/Other Names: |
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Ecology and Life History
| Lifeform: | annual herb |
| Blooming Period: May-Jul | May-Jul |
| Elevation: | 25-185 (80-605) |
| General Habitats: | Chaparral, Cismontane woodland, Valley and foothill grassland |
| Microhabitat: | Sandy |
| Microhabitat Details: |
Conservation Status
| CA Rare Plant Rank: | 1B.1 |
| Global Rank: | G4T1 |
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State Rank: |
S1 |
| State List: | CR |
| Fed List: | FE |
| Other Status: | SB_CalBG/RSABG; SB_SBBG |
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CRPR Changes: |
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Occurrence Data from the CNDDB
| Total Occurrences: | 26 |
| Element Occurrence Ranks: | |
| Excellent (A) | 2 |
| Good (B) | 8 |
| Fair (C) | 3 |
| Poor (D) | 1 |
| None (X) | 5 |
| Unknown (U) | 7 |
| California Endemic: True | |
| California Counties and Islands: Name (Code) | |
| San Luis Obispo (SLO) | |
| Quads: Name (Quad Code) | |
| Arroyo Grande NE (3512025), Morro Bay South (3512037), Oceano (3512015), Pismo Beach (3512026) | |
Threat List Data from the CNDDB
| Threat List Total: | 12 | |
| EOs with Threat Listed: | Total EOs | % of EOs |
| 21 | 81 % | |
| Development | 17 | 65% |
| Road/trail construction/maint. | 6 | 23% |
| Wood cutting or brush clearing | 6 | 23% |
| Non-native plant impacts | 5 | 19% |
| Grazing | 4 | 15% |
| Foot traffic/trampling | 3 | 11% |
| Biocides | 1 | 3% |
| Erosion/runoff | 1 | 3% |
| Mining | 1 | 3% |
| ORV activity | 1 | 3% |
| Other | 1 | 3% |
| Vandalism/dumping/litter | 1 | 3% |
Citation
California Native Plant Society, Rare Plant Program. 2025. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 6 November 2025].