| Scientific Name: | Cirsium arvense |
| Common Name: | Canada thistle |
| Family Name: | Asteraceae |
| Origin: | Central / west Asia, Europe |
| Hardiness Zone: | Zone 4: (-34 to -29 °C) |
| Plant Type: | Herbaceous perennial, Invasive plant, Weed (horticultural) |
| Mature Size: | 0.7 - 1.3m x 1.0 - 1.5m (height x width) |
| Habit: | Stiffly upright |
| Form: | Oval - vertical |
| Texture: | Medium - fine |
| Landscape Uses: | Attract birds, Wildlife food |
| Exposure: | Full sun |
| Soil or Media: | Rocky or gravelly or dry |
| Leaves: | Simple, Lobed, Alternate, Prickly, Pubescent, Oblong, Pinnately lobed, Pectinate, Spinose |
| Flowers: | Head (capitulum), Violet, Purple, Pink, Jun-Jul-Aug |
| Fruit: | Achene, Brown, Aug-Sep |
| Key ID Features: | |
| Perennial weed with rhizomes and nearby plantlets; stem leaves alternate, most oblong, 10-18cm long x 3-7cm wide, irregularly pinnately lobed with spines on margins, white pubescence on undersides; stems are spineless; flower heads unisexual, male florets 12-14mm long, female florets 22-26mm long, pink to purple, tubular; achenes 2.5-4mm long. <a href ='https://linnet.geog.ubc.ca/Atlas/Atlas.aspx?sciname=Cirsium%20arvense' target='_blank'>E-FloraBC</a> | |