Wavyleaf Thistle
Cirsium undulatum
- Native to:
- Canada, United States
iNaturalist: © sambiology (iNaturalist #86114085)
Taxonomy
- Division:
- Magnoliophyta | - Flowering plants
- Family:
- Asteraceae
- Genus:
- Cirsium
- Species:
- Cirsium undulatum
- USDA Symbol:
- CIUN
Growth Characteristics
- Life Cycle:
- Biennial | Perennial
- Growth Habit:
- Forb/herb
- Height:
- 150 cm
- Light Requirements:
- Full Sun
- Drought Tolerance:
- High
- Bloom Months:
- jun,jul,aug,sep
- Bloom Colors:
- pink, purple
Wildlife Benefits
- Bees:
- ★☆☆☆☆ Documented bee visitation (GBIF)
- Butterflies & Moths:
- ★★☆☆☆ Documented Lepidoptera association (GBIF)
Keystone Species Ranking
- Pollen Specialist Bee Keystone:
- ★★★★☆ Native pollen specialist bee species supported by this genus (NWF)
Reported Fauna Sightings
Bees: American bumble bee (Bombus pensylvanicus), Brown-belted bumble bee (Bombus griseocollis), Central bumble bee (Bombus centralis), Hunt's bumble bee (Bombus huntii), Morrison bumble bee (Bombus morrisoni), White-shouldered bumble bee (Bombus appositus), Yellow bumble bee (Bombus fervidus) Butterflies:Painted Lady (Vanessa cardui)
Garden & Ecology Notes
- Wildlife Value:
- birds, butterflies, bees
- Fire Ecology:
- Fire adapted — tolerates or benefits from fire
- Fire Notes:
- Can resprout from root crown after fire; often increases in abundance post-fire.
Soil Requirements
- Soil Type:
- sandy or gravelly, well-drained soil
- pH:
- 6.0 - 8.0 (slightly acidic to neutral)
- Drainage:
- excellent drainage required
- Moisture:
- dry to moderate
- Notes:
- commonly found in prairies and open fields
Propagation & Germination
- Stratification:
- Cold/moist stratification required — 30–60 days
- Germination Time:
- 14–30 days
- Notes:
- Seeds benefit from cold moist stratification for 4-8 weeks to break dormancy.