Taxon Report
Cirsium rhothophilum Blakesurf thistle |
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Classification
|
Scientific Name: |
Cirsium rhothophilum Blake |
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Common Name: |
surf thistle |
| Family: | Asteraceae |
| Element Code: | PDAST2E2J0 |
| USDA Plants Symbol: | CIRH |
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Synonyms/Other Names: |
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Ecology and Life History
| Lifeform: | perennial herb |
| Blooming Period: Apr-Jun | Apr-Jun |
| Elevation: | 3-60 (10-195) |
| General Habitats: | Coastal bluff scrub, Coastal dunes |
| Microhabitat: | |
| Microhabitat Details: |
Conservation Status
| CA Rare Plant Rank: | 1B.2 |
| Global Rank: | G1 |
|
State Rank: |
S1 |
| State List: | CT |
| Fed List: | None |
| Other Status: | BLM_S; SB_SBBG |
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CRPR Changes: |
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Occurrence Data from the CNDDB
| Total Occurrences: | 21 |
| Element Occurrence Ranks: | |
| Excellent (A) | 3 |
| Good (B) | 7 |
| Fair (C) | 4 |
| Poor (D) | 1 |
| None (X) | 2 |
| Unknown (U) | 4 |
| California Endemic: True | |
| California Counties and Islands: Name (Code) | |
| San Luis Obispo (SLO), Santa Barbara (SBA) | |
| Quads: Name (Quad Code) | |
| Arroyo Grande NE (3512025), Casmalia (3412075), Oceano (3512015), Pismo Beach (3512026), Point Arguello (3412056), Point Conception (3412044), Point Sal (3412086), Surf (3412065) | |
Threat List Data from the CNDDB
| Threat List Total: | 10 | |
| EOs with Threat Listed: | Total EOs | % of EOs |
| 16 | 76 % | |
| Non-native plant impacts | 8 | 38% |
| ORV activity | 6 | 28% |
| Foot traffic/trampling | 4 | 19% |
| Other | 3 | 14% |
| Development | 2 | 9% |
| Feral pigs | 1 | 4% |
| Grazing | 1 | 4% |
| Insufficient population/stand size | 1 | 4% |
| Military operations | 1 | 4% |
| Mining | 1 | 4% |
Citation
California Native Plant Society, Rare Plant Program. 2025. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 8 January 2025].