Swamp Thistle
Cirsium muticum
- Native to:
- Canada, Labrador, Prince Edward I., United States
iNaturalist: © bouteloua (iNaturalist #16339005)
Taxonomy
- Division:
- Magnoliophyta | - Flowering plants
- Family:
- Asteraceae
- Genus:
- Cirsium
- Species:
- Cirsium muticum
- USDA Symbol:
- CIMU
Growth Characteristics
- Life Cycle:
- Biennial
- Growth Habit:
- Forb/herb
- Height:
- 250 cm
- Light Requirements:
- Full Sun
- Drought Tolerance:
- Low
- Bloom Months:
- jul,aug,sep,oct
- Bloom Colors:
- pink, purple, lavender
Wildlife Benefits
- Bees:
- ★☆☆☆☆ Documented bee visitation (GBIF)
- Butterflies & Moths:
- ★☆☆☆☆ Documented Lepidoptera association (GBIF)
- Caterpillars:
- ★☆☆☆☆ Recorded caterpillar host plant (HOSTS Database)
Keystone Species Ranking
- Pollen Specialist Bee Keystone:
- ★★★★☆ Native pollen specialist bee species supported by this genus (NWF)
Host Plant for Caterpillars
⚠️Swamp Metalmark (Calephelis mutica)
Reported Fauna Sightings
Bees: Common eastern (Bombus impatiens), eastern thistle longhorn bee (Melissodes desponsus), Fernald cuckoo bumble bee (Bombus flavidus), Fuzzy-horned bumble bee (Bombus mixtus), Indiscriminate cuckoo bumble bee (Bombus insularis), Pyrobombus Dalla, Two-form bumble bee (Bombus bifarius), Yellow bumble (Bombus fervidus), Yellow head bumble bee (Bombus flavifrons), Yellow-faced bumble bee (Bombus vosnesenskii) Butterflies:Eastern Tiger Swallowtail (Papilio glaucus), Great Spangled (Argynnis cybele), ⚠️Monarch butterfly (Danaus plexippus)
Garden & Ecology Notes
- Wildlife Value:
- bees, butterflies, birds
- Deer Resistant:
- Yes
Soil Requirements
- Soil Type:
- rich, moist, organic soil
- pH:
- 5.5 - 7.0 (slightly acidic to neutral)
- Drainage:
- tolerates poor drainage
- Moisture:
- consistently moist
- Notes:
- commonly found in wetlands and marshes
Propagation & Germination
- Stratification:
- Cold/moist stratification required — 30–60 days
- Germination Time:
- 14–30 days
- Notes:
- Seeds germinate readily after cold stratification. Light may improve germination rates.
The above propagation data sourced from Claude AI