Canadian Horseweed

Erigeron canadensis

Native to:
Bahamas, Belize, Bolivia, Brazil, Canada, Cayman Is., Colombia, Costa Rica, Dominican Republic, El Salvador, French Guiana, Galápagos, Guam, Guatemala, Haiti, Honduras, Jamaica, Leeward Is., Mexico, Navassa Island, Nicaragua, Palau, Panamá, Peru, Prince Edward I., Puerto Rico, Suriname, Trinidad-Tobago, Turks-Caicos Is., U.S. Minor Outlying Islands, United States, Virgin Islands, Windward Is.

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Asteraceae
Genus:
Erigeron
Species:
Erigeron canadensis
USDA Symbol:
COCA5

Growth Characteristics

Life Cycle:
Annual | Biennial
Growth Habit:
Forb/herb
Height:
150 cm
Light Requirements:
Full Sun
Drought Tolerance:
High
Bloom Months:
jun,jul,aug,sep,oct
Bloom Colors:
white, greenish-white

Wildlife Benefits

Bees:
★☆☆☆☆ Documented bee visitation (GBIF)
Butterflies & Moths:
★☆☆☆☆ Documented Lepidoptera association (GBIF)
Caterpillars:
★★☆☆☆ Recorded caterpillar host plant (HOSTS Database)

Keystone Species Ranking

Caterpillar Keystone:
★★★☆☆ Butterfly & moth species supported by this genus (NWF)
Pollen Specialist Bee Keystone:
★★★★☆ Native pollen specialist bee species supported by this genus (NWF)

Host Plant for Caterpillars

blackberry looper (Chlorochlamys chloroleucaria), common eupithecia (Eupithecia miserulata), Cucullia florea, Sharp Stigma Looper (Ctenoplusia oxygramma), Sicya sp., sparganothis fruitworm moth (Sparganothis sulfureana), Speyer's Hooded Owlet (Cucullia speyeri), Variegated cutworm (Peridroma saucia), Wavy-lined Emerald (Synchlora aerata), Yellow-striped armyworm (Spodoptera ornithogalli), orange oakleaf (Charidryas nycteis)

Reported Fauna Sightings

Moths:Parectopa plantaginisella

Garden & Ecology Notes

Wildlife Value:
birds, butterflies, small mammals
Deer Resistant:
Yes
Fire Ecology:
Fire adapted — tolerates or benefits from fire
Fire Notes:
Pioneer species that readily colonizes disturbed and burned areas from wind-dispersed seed.

Soil Requirements

Soil Type:
poor, sandy, well-drained soil
pH:
4.5 - 7.5 (acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
commonly found in disturbed areas and roadsides

Propagation & Germination

Stratification:
None required
Germination Time:
7–21 days
Notes:
Seeds require light for germination; surface sow and do not cover. Germinates readily at temperatures between 65-75°F.

The above propagation data sourced from Claude AI

Pre-treatment: Single-step cold-moist stratification for temperate woodland species. for 60–120 days

Notes: Seeds germinate readily without pretreatment.

Source: Claude AI