Red Ash

Fraxinus pennsylvanica

Pollinator Value

🔑 Keystone: Fraxinus supports 128 species of butterflies and moths as a caterpillar host plant in the Ottawa ecoregion. Three native ash species (F. pennsylvanica, F. nigra, F. americana) collectively sustain this rich lepidopteran community, including large silkmoths (Cecropia, Polyphemus, Promethea), sphinx moths, and the Eastern Tiger Swallowtail. The genus is a top-tier keystone for insect biodiversity in northeastern forests.
S13 128 lepidoptera; S14 67 host records
🐛 Larval Host: Ceratomia amyntor, Nymphalis antiopa, Sphinx kalmiae, Sphinx gordius, Papilio glaucus, Callosamia promethea, Paonias excaecatus, Euclea delphinii, Lophocampa caryae, Schizura concinna, Antheraea polyphemus, Automeris io, Hyalophora cecropia, Orgyia leucostigma, Copivaleria grotei
S13+S15 15 verified Eastern NA
❄️ Winter Food Source: Samaras persist into winter and are consumed by Evening Grosbeak (Coccothraustes vespertinus) and Pine Grosbeak (Pinicola enucleator). Seeds also eaten by Wood Duck, Wild Turkey, Bobwhite Quail, Northern Cardinal, and Purple Finch. Fox Squirrel and White-footed Mouse forage on fallen seeds through the cold months.
S57 Evening Grosbeak, Pine Grosbeak; S10 seed-eating birds and mammals

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: Not listed under SARA. NatureServe global rank G4 but IUCN status Critically Endangered due to devastating impacts of the Emerald Ash Borer (Agrilus planipennis). Quebec rank S3 (Vulnerable) reflects ongoing population decline from EAB infestation. Ontario rank S4 (Apparently Secure) indicates larger remaining populations but continued monitoring warranted.
S22 G4, IUCN CR; S26 not SARA listed; S29 EAB context
Rarity Ranks: QC S3 – Vulnerable, ON S4 – Apparently Secure
Migration: Stable
Ecological Context: Green ash is a floodplain and riparian tree, naturally occurring along streams, rivers, and wet bottomlands. In the Ottawa-Gatineau region it inhabits alluvial soils subject to seasonal flooding, often alongside silver maple, American elm, and eastern cottonwood. It colonizes early in succession on disturbed alluvial sites, tolerates prolonged spring flooding, and its extensive lateral root system makes it relatively windfirm.
S41 floodplain pioneer; S10 moist bottomlands; S7 swamps, shores, floodplains

Roles: Fire Retardant, Fortress/Barrier, Wildlife Habitat
S73/S29/S72 Evidence: Fire Retardant: S73 [MEDIUM]: S11 Fire Tolerance = Medium (not definitional)] | Fortress/Barrier: S61 keyword match: thorns? (supporting signal only)] | Wildlife Habitat: S72 Hemenway (tables: 7-2, pp. 116)]
Notes: Excellent shelterbelt and windbreak species for exposed sites; tolerates atmospheric pollution. Can serve as a substitute for invasive Rhamnus cathartica or Acer platanoides in landscape plantings. In food forest design, functions as a canopy-layer wildlife habitat tree providing seed for birds. Tolerates juglone from black walnut.
S29 shelterbelt; S3 tolerates juglone; S72 wildlife habitat

Category: Psychological Aid, Stimulant, Tonic, Diuretic
S28 Moerman Drug categories; S29 PFAF medicinal categories
Notes: Algonquin (Tete-de-Boule) used infusion of inner bark for depression and fatigue. Ojibwa used compound containing inner bark as a tonic. The bark and leaves are described as a bitter tonic. The root is diuretic.
S28 Moerman ethnobotanical records; S29 PFAF bitter tonic, diuretic

✅ Edible

Foraging Notes: Inner bark (cambium) can be scraped into fluffy layers and cooked; reported to taste like eggs. Inner bark can also be dried, ground into powder, and used as thickener in soups or mixed with cereals for bread. Very limited traditional food use.
S29 PFAF edible inner bark; S28 Moerman Food=1 use