American Mountain-ash

Sorbus americana

Pollinator Value

🔑 Keystone: Sorbus supports 72 species of butterflies and moths as a caterpillar host plant in the region. This genus-level count includes support for charismatic species such as the Mourning Cloak (Nymphalis antiopa), Eastern Tiger Swallowtail (Papilio glaucus), and Cecropia Silkmoth (Hyalophora cecropia), making it a significant contributor to Lepidoptera diversity in mixed northern forests.
S13
🐛 Larval Host: Nymphalis antiopa, Acronicta interrupta, Limenitis arthemis, Xanthotype sospeta, Papilio glaucus, Antheraea polyphemus, Hyalophora cecropia, Orgyia leucostigma, Podosesia syringae, Venusia comptaria
S13+S15 10 verified Eastern NA
❄️ Winter Food Source: Bright red to orange-red pomes (4-7 mm) persist into winter, providing critical forage for American Robin, Spruce Grouse, Swainson's Thrush, and Veery. Go Botany notes that waxwings, robins, jays, and grouse also consume the berries. Hemenway lists mountain ash as providing fruit services for birds.
S57+S61+S72

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: Globally secure (G5) with IUCN status of Least Concern. Not listed under SARA. Ranked S5 in both Ontario and Quebec. Nationally ranked N5 in Canada. Locally uncommon in the Ottawa region and sparse in the Hull-Ottawa area, but widespread across eastern North America.
S22+S26+S62+S63
Rarity Ranks: QC S5 – Secure, ON S5 – Secure
Migration: Stable
Ecological Context: A small understory tree of cool, moist northern forests, typically found along lake and stream shores, on rocky hillsides, in thickets, and at the borders of mixed woods. In Michigan, documented in cedar and deciduous swamps, stream banks, and bluffs along Lake Superior. In the Ottawa region it is uncommon; listed as sparse in the Hull-Ottawa area by Gillett & White. Favours acidic to circumneutral soils in the mixed wood shield.
S6+S7+S62+S63

Roles: Fortress/Barrier, Wildlife Habitat
S73/S29/S72 Evidence: Fortress/Barrier: S61 keyword match: thorns? (supporting signal only)] | Wildlife Habitat: S72 Hemenway (tables: 10-1, 7-2, pp. 116, 149)]
Notes: Listed by Hemenway as a low tree layer component in wildlife habitat guilds, providing fruit services for birds. PFAF categorizes it for Woodland Garden Canopy, Secondary, and Sunny Edge plantings. Its small stature and wildlife value make it suitable as an understory companion in mixed northern forest guilds.
S72+S29

Category: Analgesic, Antiseptic, Antiscorbutic, Appetizer, Astringent, Blood purifier, Cold Remedy, Dermatological Aid, Dietary Aid, Digestive, Diuretic, Emetic, Gastrointestinal Aid, Gynecological Aid, Laxative, Psychological Aid, Pulmonary Aid, Strengthener, Tonic, Venereal Aid
S28+S29
Notes: Extensively used by First Nations peoples across northeastern North America. Algonquin of Quebec used inner bark infusions for colds and as a tonic with sweet flag. Malecite and Micmac used bark for pain after childbirth, boils, and as an emetic. Montagnais used bark decoctions to purify blood and stimulate appetite. Ojibwa used root bark for gonorrhea. PFAF notes the inner bark has astringent and antiseptic properties, and the fruit is antiscorbutic, diuretic, mildly laxative, and digestive.
S28+S29

✅ Edible

Foraging Notes: Fruit edible raw or cooked, rich in iron and vitamin C. Used mainly in pies and preserves; becomes sweeter after frost. High tannin content limits raw consumption. Algonquin, Montagnais, and Ojibwa peoples used berries as food. Fruit can also be dried and ground into a meal.
S29+S28