Southern Horseweed
Conyza canadensis var. pusilla
In the Carolinas and Georgia, found in dunes, brackish marsh edges, coastal sand flats, sand prairies, old fields, disturbed areas, barrens and glades. Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition What its natural habitat tells you
Native to Louisiana (estimated). How scores work Is it native here?
Profile 71%
- Light
- Partial shade, Full sun
- Soil moisture
- Dry to wet
At a glance
- Life cycle
- Annual or biennial
Not yet recorded · Height · Spread · Leaves · Bloom
This plant is missing most of its facts, so Quercus is looking them up in old botany books.
Recorded in 26 Louisiana parishes.
Natural habitats
Places it grows wild. Not a planting requirement. Each habitat page lists the plants and wildlife also found there.
Open sand of beaches, dunes and the hollows between them.
Coastal marshes flooded by salty or brackish tides.
Open, grass-dominated places kept open by fire, grazing or thin soil, from tallgrass prairie to Piedmont prairies.
Roadsides, fields and disturbed ground
Ground opened by people: roadsides, old fields, pastures, fencerows and lots.
Who uses this plant?
25CaterpillarsGenus host records with ranges including LA
Genus host records with ranges including LA · Erigeron
- Archips purpuranaOmnivorous Leafroller Moth
- Bucculatrix angustataNarrow Bucculatrix
- Chlorochlamys chloroleucariaBlackberry Looper Moth
- Chlosyne nycteisSilvery Checkerspot
- Ctenoplusia oxygrammaSharp-Stigma Looper Moth
- Eugnosta erigeronanaFleabane Cochylid
- Eupithecia miserulataCommon Eupithacia, Common Pug
- Herpetogramma pertextalisBold-Feathered Grass Moth
- Herpetogramma thestealisZigzag Herpetogramma, Subtle-Feathered Grass Moth
- Hyles lineataWhite-Lined Sphinx
Show all 25
- Leuconycta diphteroidesGreen Leuconycta
- Lioptilodes albistriolatusMousy Plume Moth
- Papaipema nebrisStalk Borer
- Phyciodes tharosPearl Crescent, Crescentspot
- Platynota stultanaOmnivorous Leafroller
- Schinia arcigeraArcigera Flower Moth
- Schinia lynxLynx Flower Moth
- Schinia obscurataObscure Schinia Moth, Erigeron Flower Moth
- Sparganothis sulfureanaSparganothis Fruitworm Moth, Sulfur Leafroller, False Yellow-Head
- Spodoptera frugiperdaFall Armyworm Moth
- Spodoptera ornithogalliYellow-Striped Armyworm Moth, Cotton Cutworm
- Synchlora frondariaSouthern Emerald
- Thyridopteryx ephemeraeformisEvergreen Bagworm Moth
- Hellinsia chlorias
- Xenotemna pallorana
74BeesSoutheastern regional records
Southeastern regional records · Erigeron
Individual names are not available yet.
Noori, Seltmann & Orr 2026, A curated and integrated dataset for exploring global bee-plant interactions (GloBI), Zenodo, CC BY 4.0
9Specialist beesPollen specialists
Pollen specialists · Erigeron
- Andrena asteris
- Andrena fulvipennis
- Andrena nubecula
- Andrena simplex
- Colletes americanus
- Colletes simulans
- Melissodes illatus
- Perdita boltoniae
- Protandrena aestivalis
4BirdsRecorded genus food-resource interactions; not a state feeding claim
Recorded genus food-resource interactions; not a state feeding claim · Erigeron
- Callipepla californicaCalifornia Quail
- Dendragapus obscurusDusky Grouse
- Meleagris gallopavoWild Turkey
- Tympanuchus pallidicinctusLesser Prairie-Chicken
Direct food only: birds recorded eating this genus across North America. Caterpillars on host plants also feed nesting birds. NC Native Plant Society: butterfly gardening
No records yet · Ants · Beetles · Flies · Adult butterflies / moths · Other wasps · Other insects
Plant details
- Family
- Asteraceae
- Flower color
- White
Safety has not been reviewed for this plant; check toxicity and thorns before planting.
Growing sources and scope
- Flower color · “White” · Lady Bird Johnson Wildflower Center
- Life cycle · “Annual or biennial” · Lady Bird Johnson Wildflower Center
- Light · “Partial shade; Full sun (documented habitat)” · Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition · Carolinas and Georgia
- primary_flower_color · “white” · Lady Bird Johnson Wildflower Center
- Soil · “Dry; Moist; Wet (documented habitat)” · Weakley, Flora of the Southeastern United States (2025), Carolinas & Georgia edition · Carolinas and Georgia
Also known as
Barrilla; Canadian Horse Weed; Canadian Horseweed; Conyza canadensis var. pusilla; Erigeron canadensis var. pusillus; Southern Horse Weed
Conservation status
| Louisiana rank | SNR |
|---|---|
| Global rank | G5T5 [G5] |
| LA status | Not verified |
| Federal status | Not verified |
Will it fit your yard?
Check this plant against your county, sun and soil moisture. Conditions are checked in your browser.
Sources
- USDA PLANTS
- Vascular Plants of North Carolina (NC Natural Heritage Program)
- Weakley, Flora of the Southeastern United States (2025)
- Louisiana occurrence source
- Shropshire & Tallamy 2025, Lepidoptera of North America north of Mexico, ZooKeys 1261 (ODbL)
- Noori, Seltmann & Orr 2026, A curated and integrated dataset for exploring global bee-plant interactions (GloBI), Zenodo, CC BY 4.0
- Smith, Bachelder, Russell, Morales, Mosher & Seltmann 2024, Bee-Specialization-Modeling v0.6.1 (specialist host table compiled from J. Fowler's pollen specialist bee lists), Zenodo, CC BY 4.0
- Hurlbert, Olsen, Sawyer & Winner 2021, Avian Diet Database, Scientific Data 8: 260 (CC0)
- Narango, Tallamy & Shropshire 2020, Few keystone plant genera support the majority of Lepidoptera species, Nature Communications