White Trillium

Trillium grandiflorum

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: Secure in Ontario (S5) but vulnerable in Quebec (S3), where populations are at the northeastern edge of the range. Not listed under SARA or COSEWIC. Globally secure (G5, IUCN Least Concern). Deer browse pressure is a significant threat to wild populations across the range.
S22+S26+S10
Rarity Ranks: QC S3 – Vulnerable, ON S5 – Secure
Migration: Stable
Ecological Context: A spring ephemeral of rich deciduous forests, most characteristically found in mature sugar maple-beech stands on mesic, well-drained soils. Thrives in deep humus with neutral to slightly calcareous substrates. Also occurs in mixed coniferous-deciduous upland woods, floodplains, and shaded riverbanks from 20-700 m elevation. Forms colonies via slow rhizome expansion. Ant-dispersed seeds (myrmecochory) link it tightly to intact forest ant communities.
S6+S7+S10+S29

Roles: Pollinator Attractor
S73/S29/S72 Evidence: Pollinator Attractor: S73 [MEDIUM]: S68 4 bee associations (threshold=3)]
Notes: Excellent woodland ground layer companion for spring ephemeral guilds. Pairs well with other spring ephemerals (Erythronium, Anemone) that share similar light and moisture requirements under deciduous canopy. Tolerates juglone, making it suitable beneath black walnut.
S3+S29

Category: Analgesic, Antirheumatic, Diuretic, Emmenagogue, Ophthalmic, Ear Medicine, Gynecological Aid
S28 Moerman Drug categories; S29 Antispasmodic, Diuretic, Emmenagogue, Ophthalmic
Notes: Extensively used by Chippewa, Menominee, and Potawatomi peoples. Root decoctions applied externally for rheumatic joints (Chippewa) and as ear drops (Chippewa). Grated raw root poulticed on eye swellings (Menominee) and steeped for cramps and irregular menses (Menominee). Root infusion used as diuretic (Menominee) and for sore nipples (Potawatomi).
S28+S29

❌ Not Edible

Foraging Notes: Young unfolding leaves reportedly cooked like spinach, but considered a famine food only (edibility rating 1/5). Harvesting leaves kills the plant since it cannot regenerate without foliage. Berries and roots have low toxicity if eaten. Not a culinary species.
S29+S4