Stiff Sunflower

Helianthus pauciflorus

Pollinator Value

🔑 Keystone: Helianthus is a top-tier keystone genus in Eastern North America, supporting 52 species of butterflies and moths as caterpillar host plants. Four native Helianthus species occur in the local area, collectively providing critical lepidopteran habitat through summer and fall.
S13 52 lepidoptera spp., 4 local native Helianthus species
🐛 Larval Host: Hypercompe scribonia, Pyrrharctia isabella, Orgyia leucostigma, Euxoa albipennis, Ogdoconta cinereola, Euxoa ochrogaster, Aglais milberti
S13+S15 7 verified Eastern NA
🐝 Specialist Bee Host: Andrena helianthi, Melissodes agilis, Melissodes denticulatus, Melissodes druriellus, Melissodes trinodis
S17 Helianthus pollen specialists with Eastern NA ranges; Andrena helianthi is a strict Helianthus specialist
❄️ Winter Food Source: Sunflower seeds (cypselae) persist on standing dead stems through winter, providing high-energy food for seed-eating birds. The Avian Diet Database records Helianthus seeds in the diets of 39 bird species including American Goldfinch, Mourning Dove, Red-winged Blackbird, Brown-headed Cowbird, Common Grackle, and White-breasted Nuthatch.
S57 39 bird species including granivores and finches

Proximity Score: 0
Native Status: ❌ Outaouais ❌ Ottawa ❌ QC ✅ ON
Closest Direction: Local
CEC Eco-Regions: 5 – Northern Forests, 5.2 – Mixed Wood Shield, 5.2.3 – Algonquin/Southern Laurentians
Rarity Notes: Imperiled (S2) in Ontario, reflecting limited populations concentrated in prairie remnants and railway corridors. Not listed under SARA or COSEWIC. Globally secure (G5) with wide distribution across the Great Plains. Quebec specimens from Nominingue, Lac Megantic, and Montreal area may represent adventive or naturalized populations.
S22 S2 ON, G5, N4 Canada; S26 SARA not listed; S54 QC specimens
Rarity Ranks: QC SNR – Not Ranked, ON S2 – Imperiled
Migration: Stable
Ecological Context: A prairie and open-habitat perennial of dry to mesic grasslands, roadsides, and disturbed ground. In Ontario it is rare (S2 Imperiled), occurring primarily in open calcareous sites. Rhizomatous and colony-forming, it thrives on sandy to clay soils in full sun. Historically associated with tallgrass prairie remnants and railway corridors, where it persists as scattered populations.
S7 prairie habitats, railroads, burned areas; S22 S2 in ON; S29 dry to moist prairies; S6 habitat data

Roles: Fortress/Barrier, Insectary Plant, Pollinator Attractor
S73/S29/S72 Evidence: Fortress/Barrier: S61 keyword match: spines? (supporting signal only)] | Insectary Plant: S64 NPPBI 'beneficial insects' flag] | Pollinator Attractor: S73 [HIGH]: S64 Xerces listed (source-classified)]
Notes: Suited to perennial polyculture and prairie restoration plantings. Attracts a wide variety of solitary bees and beneficial insects, serving as an insectary plant in guild designs. Caution: rhizomatous spread can crowd out smaller companions in confined plantings.
S29 polyculture; S64 attractive to solitary bees, can crowd out other plants

✅ Edible

Foraging Notes: Seeds are protein- and oil-rich, comparable to cultivated sunflower. The Land Institute is actively developing perennial sunflower crops including H. pauciflorus as part of perennial polyculture systems for oil-seed production. Seeds can be harvested and processed similarly to annual sunflower seeds.
S29 edible parts=oil, seed; Edibility Rating 4/5; Land Institute perennial polyculture