Twinleaf

Jeffersonia diphylla

Ecology & Conservation

Proximity Score: 2
Native Status: ❌ Outaouais ❌ Ottawa ❌ QC ✅ ON
Closest Direction: SW
CEC Eco-Regions: 8 – Eastern Temperate Forests, 8.1 – Mixed Wood Plains, 8.1.2 – Lake Erie Lowland
Rarity Notes: Globally secure (G5) with a Canadian national rank of N4 (S22). Ranked S4 in Ontario, its only Canadian province of occurrence. Not listed under SARA or COSEWIC (S26). In Ontario, populations are uncommon and local, closely tied to calcareous river valley habitats, though plants can be locally abundant where found (S7).
S22 S26 S7
Rarity Ranks: QC SNA – Not Applicable, ON S4 – Apparently Secure
Migration: Stable
Ecological Context: Occurs in rich mesic deciduous forests, especially on floodplains and well-drained slopes above floodplains, usually over limestone or other calcareous rocks at 100-800 m elevation. Typically closely associated with major river systems and their tributaries. Common associates include Acer saccharum, Fagus grandifolia, Caulophyllum thalictroides, Trillium grandiflorum, Sanguinaria canadensis, and Erythronium americanum in mature beech-maple and maple-basswood communities.
S6 S7 S4

Roles: ground cover, early pollinator support
S29 woodland garden ground cover; S68 early spring bee visits
Notes: A characteristic member of rich mesic deciduous woodland guilds, particularly beech-maple and maple-basswood communities on calcareous substrates. Pairs naturally with spring-blooming forest herbs including Caulophyllum thalictroides, Trillium grandiflorum, and Sanguinaria canadensis in the herb layer beneath Acer saccharum and Fagus grandifolia canopy (S7). PFAF notes suitability for woodland garden and food forest understory plantings in dappled shade (S29).
S7 S29

Category: Dermatological Aid, Kidney Aid, Urinary Aid, Antidiarrheal, Liver Aid, Antispasmodic, Diuretic, Emetic, Expectorant
S28 Cherokee and Iroquois uses; S29 PFAF medicinal properties
Notes: Extensively used by Cherokee and Iroquois peoples. Cherokee applied poultices for sores, ulcers, and inflammation, and prepared infusions for dropsy, gravel, and urinary problems (S28). Iroquois used decoctions of the whole plant for diarrhea in adults and children, and for gall/liver complaints (S28). The root is emetic in large doses and expectorant in smaller doses; it contains berberine, which has demonstrated anti-tumour activity (S29).
S28 S29

❌ Not Edible

Foraging Notes: No edible uses are documented. PFAF assigns an edibility rating of 0/5 and lists no edible parts (S29). Moerman records only medicinal uses, with no Food category entries (S28).
S29 S28