Pale-leaved Sunflower
Helianthus strumosus
- Plant Type
- Forb/herb (Deciduous)
- Landscape Layer
- Herb
- Sun
- ☀️ Full Sun, ⛅ Part Sun, ☁️ Shade
- Moisture
- 🏜️ Dry, 💧 Regular
- Soil
- Clay, Loam, Sand, Silt, Rocky / Acidic, Calcareous
- Bloom
- July, August, September
- Sociability
- S4 – Large patches
Pollinator Value
- 🔑 Keystone
- Helianthus is a top-tier keystone genus supporting 52 species of butterflies and moths as caterpillar host plants in the Ottawa-Gatineau ecoregion. Four Helianthus species are native locally, collectively sustaining a large guild of Lepidoptera, including generalist moths (Hypercompe scribonia, Pyrrharctia isabella) and sunflower specialists (Cochylis hospes). The genus also supports 36 specialist bee species across eastern North America, making it one of the most ecologically consequential plant genera for pollinator conservation.
- 🐛 Larval Host
- Hypercompe scribonia, Pyrrharctia isabella, Orgyia leucostigma, Euxoa albipennis, Ogdoconta cinereola, Euxoa ochrogaster, Aglais milberti
- 🐝 Specialist Bee Host
- Andrena helianthi, Andrena accepta, Andrena aliciae, Andrena chromotricha, Andrena peckhami, Melissodes agilis, Melissodes denticulatus, Melissodes dentiventris, Melissodes druriellus, Melissodes illatus, Melissodes trinodis, Svastra obliqua, Colletes americanus, Dieunomia heteropoda, Pseudopanurgus labrosiformis, Pseudopanurgus labrosus, Pseudopanurgus rugosus, Megachile pugnata, Paranthidium jugatorium
S17 Fowler pollen specialists on Helianthus with Eastern NA ranges
- ❄️ Winter Food Source
- Helianthus seeds persist on standing stems through winter, providing critical food for overwintering and migrant birds. The Avian Diet Database documents 39 bird species feeding on Helianthus seeds, including American Goldfinch, American Crow, White-breasted Nuthatch, Downy Woodpecker, Red-headed Woodpecker, Mourning Dove, and Wild Turkey. Standing seed heads are especially valuable for finches and sparrows during late fall and winter months.
S57 39 bird species including American Goldfinch, White-breasted Nuthatch, Downy Woodpecker; S4 seed heads attract birds
Ecology & Conservation
- 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
- Ranked S2 (Imperiled) in Quebec, indicating very few known occurrences or significant decline risk. In contrast, ranked S5 (Secure) in Ontario and G5 globally. Not listed under SARA or COSEWIC. The Quebec imperilment likely reflects the species being near its northeastern range limit, with most populations concentrated in the St. Lawrence Lowlands and southern Quebec. Six Quebec herbarium specimens in CNH/MT collections span 1893 to 2018.
S22 S2 QC, G5 global; S26 not SARA listed; S54 6 QC specimens 1893-2018
- Rarity Ranks
- QC S2 – Imperiled, ON S5 – Secure
- Migration
- Stable
- Ecological Context
- Pale-leaved sunflower is a rhizomatous perennial of dry upland woods, woodland edges, roadsides, and clearings. In the Ottawa-Gatineau region it occupies deciduous and mixed forests on well-drained sandy or loamy soils, often forming dense patches along forest margins. Michigan Flora associates include Acer saccharum, Fagus grandifolia, Quercus rubra, and Q. alba in dry-mesic southern forest. Ranked S2 (Imperiled) in Quebec but S5 (Secure) in Ontario, suggesting the species is near its northeastern range limit in Quebec.
S4 dry open upland woods, woodland edges; S7 dry sandy ground, oak forests; S22 S2 QC, S5 ON; S61 deciduous forests, meadows, riverbanks
Permaculture & Companion Planting
- Roles
- Fortress/Barrier, Pollinator Attractor
S73/S29/S72 Evidence: Fortress/Barrier: S61 keyword match: spines? (supporting signal only)] | Pollinator Attractor: S73 [HIGH]: S64 Xerces listed (source-classified)]
- Notes
- An excellent woodland edge companion forming dense colonies that stabilize soil and provide continuous late-season bloom (Jul-Sep) when many spring-blooming species have finished. Its running rhizomes create a living ground-cover matrix beneath open canopy trees. Supports an exceptionally large guild of specialist pollinators (36 bee species on Helianthus), making it a powerful pollinator attractor when interplanted with other Asteraceae. PFAF recommends cultivated beds and sunny woodland edges.
S29 woodland garden; S17 36 specialist bees; S4 bloom Jul-Sep
Medicinal Properties ℹ
Always consult a qualified healthcare provider before using any plant for medicinal purposes. The information provided is compiled from secondary sources for educational purposes only.
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ℹ
Always consult a qualified healthcare provider before using any plant for medicinal purposes. The information provided is compiled from secondary sources for educational purposes only.
Click here for more info →- Category
- Anthelmintic, Pediatric Aid, Pulmonary Aid
S28 Moerman categories: Drug Anthelmintic, Drug Pediatric Aid, Drug Pulmonary Aid
- Notes
- The Iroquois used a root decoction as an anthelmintic to treat intestinal worms in both adults and children. The Meskwaki prepared a root infusion for lung troubles. Health Canada NHPID classifies Helianthus strumosus as an Approved Herbal Name under Schedule 1 (plant and plant material), with whole plant used in dry and fresh preparations.
S28 Iroquois anthelmintic + pediatric, Meskwaki pulmonary; S36 Health Canada NHPID approved; S61 Iroquois root decoction for worms
Edibility & Foraging ℹ
Never ingest a plant unless you have 100% certainty of its identity and have consulted multiple reputable sources. The information provided in the Localeaf Plant Database is compiled from secondary sources for educational and historical purposes only.
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ℹ
Never ingest a plant unless you have 100% certainty of its identity and have consulted multiple reputable sources. The information provided in the Localeaf Plant Database is compiled from secondary sources for educational and historical purposes only.
Click here for more info →❌ Not Edible
- Foraging Notes
- PFAF lists the root as edible, noting it is 'probably used raw or cooked like the Jerusalem artichoke' but provides no detailed preparation information. Moerman (NAEB) records no food uses; all three ethnobotanical entries are medicinal (Drug category). PFAF edibility rating is 2 out of 5. The roots produce small tubers comparable to Jerusalem artichoke (H. tuberosus) but are not widely harvested.
Seed Source
- OWSL