Taxonomy

Division:

Magnoliophyta | - Flowering plants

Family:

Asteraceae

Genus:

Cirsium

Species:

Cirsium arizonicum

USDA Symbol:

CIAR3

Growth Characteristics

Life Cycle:

Biennial | Perennial

Growth Habit:

Forb/herb

Height:

120 cm

Light Requirements:

Full Sun

Drought Tolerance:

High

Bloom Months:

jun,jul,aug,sep

Bloom Colors:

red, pink, magenta

Wildlife Benefits

Bees:

★★★☆☆ Documented bee visitation (GBIF)

Butterflies & Moths:

★☆☆☆☆ Documented Lepidoptera association (GBIF)

Hummingbirds:

★☆☆☆☆ Documented hummingbird visits (GBIF)

Keystone Species Ranking

Pollen Specialist Bee Keystone:

★★★★☆ Native pollen specialist bee species supported by this genus (NWF)

Reported Fauna Sightings

Garden & Ecology Notes

Wildlife Value:

bees, butterflies, birds

Fire Ecology:

Fire adapted — tolerates or benefits from fire

Fire Notes:

Resprouts from root crown after fire; seeds germinate well in post-fire conditions.

Soil Requirements

Soil Type:

rocky, well-drained, nutrient-poor soil

pH:

6.0 - 8.0 (slightly acidic to neutral)

Drainage:

excellent drainage required

Moisture:

dry to moderate

Notes:

commonly found in arid, mountainous regions

Propagation & Germination

Stratification:

Cold/moist stratification required — 30–60 days

Germination Time:

14–30 days

Notes:

Seeds benefit from cold stratification for 4-8 weeks to break dormancy.