| Taxon | Cirsium occidentale var. californicum |
| group | Eudicots |
| Family | Asteraceae |
| Family common name(s) | composite; composita; comp; aster; asterwort; asterworts; sunflower; daisy; dandelion |
| Genus common name(s) | cirsium; thistle; true thistle; plume thistle; plume-thistle |
| Species common name(s) | western thistle; cobwebby thistle; cobweb thistle; cob-web thistle; cob web thistle |
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| Common name(s) generally applied to other taxa or multiple taxa | California thistle, Californian thistle are applied inappropriately to Cirsium arvense; red thistle is applied to multiple Cirsium taxa |
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| Notes | California, Californian, Bigelow are proper names, so upper case preferable; Bigelows, Bigelov's, Bigelo are errors |
| Synonymy: The Jepson Manual (1993), FNA, PLANTS, etc | Cirsium californicum A. Gray |
