Trembling Aspen

Populus tremuloides

Pollinator Value

🔑 Keystone: Populus supports 352 species of butterflies and moths as caterpillar host plants in the Outaouais ecoregion, making it one of the most ecologically significant genera for Lepidoptera. Key species include Mourning Cloak (Nymphalis antiopa), Viceroy (Limenitis archippus), and Eastern Tiger Swallowtail (Papilio glaucus). The genus also supports numerous leaf beetles, borers, and sap-feeding insects that form the base of woodland food webs.
S13 352 lepidoptera; S10 extensive insect associations
🐛 Larval Host: Agriopodes fallax, Furcula scolopendrina, Polygonia interrogationis, Furcula borealis, Polygonia faunus, Limenitis archippus, Nymphalis antiopa, Paonias myops, Orgyia definita, Sphinx kalmiae, Limenitis arthemis, Xanthotype sospeta, Papilio glaucus, Acronicta funeralis, Callosamia promethea
S13+S15 15 verified Eastern NA
❄️ Winter Food Source: Buds and catkins are a critical winter food for Ruffed Grouse (up to 40% of diet by weight) and are also consumed by Rock Ptarmigan, Willow Ptarmigan, and Spruce Grouse. Bark below the snow line is gnawed by Meadow Voles through winter. Beaver cache branches for winter consumption, and White-tailed Deer browse persistent twigs.
S57 Ruffed Grouse 40% diet; S10 Meadow Vole bark, Beaver branches

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) and secure in both Ontario (S5) and Quebec (S5). Not listed under SARA or COSEWIC. The most widely distributed native tree in North America, occurring across all Canadian provinces and territories. No conservation concerns.
S22 G5, S5/S5; S26 not SARA listed; S41 widest distribution of any native NA tree
Rarity Ranks: QC S5 – Secure, ON S5 – Secure
Migration: Stable
Ecological Context: A dominant pioneer tree of the boreal-mixedwood transition, trembling aspen rapidly colonizes burned, logged, or otherwise disturbed sites via aggressive root suckering, forming extensive clonal colonies. In the Outaouais it occupies upland woodlands, sandy thickets, and woodland edges on a wide range of soils from shallow rocky outcrops to deep loams. It is eventually replaced by shade-tolerant species such as sugar maple and balsam fir in the absence of recurring disturbance.
S41 pioneer, wide soil range; S10 pioneer of disturbed habitats; S7 tolerates colder/wetter situations

Roles: Fire Retardant, Fortress/Barrier, Nurse Plant, Pollinator Attractor
S73/S29/S72 Evidence: Fire Retardant: S73 [HIGH]: S11 Fire Resistant = Yes (definitional)] | Fortress/Barrier: S61 keyword match: thorns? (supporting signal only)] | Nurse Plant: S10 keyword match: pioneer (supporting signal only)] | Pollinator Attractor: S73 [HIGH]: S64 Xerces listed (source-classified)]
Notes: As a fast-growing pioneer, trembling aspen rapidly establishes canopy cover on disturbed sites and provides excellent nurse conditions for shade-tolerant species to establish beneath. Its shallow lateral root system and light crown allow understorey development. The leaf litter decomposes rapidly, cycling calcium, magnesium, and nitrogen back to the soil, enriching conditions for successor species.
S41 nutrient cycling, nurse canopy role; S29 pioneer providing conditions for establishment

Category: Analgesic, Anti-inflammatory, Antiseptic, Astringent, Diaphoretic, Diuretic, Febrifuge, Nervine, Dermatological Aid, Anthelmintic
S29 anodyne/anti-inflammatory/antiseptic/astringent/diaphoretic/diuretic/febrifuge/nervine; S28 dermatological, anthelmintic, gynecological uses
Notes: Bark contains salicylates (the chemical basis of aspirin) and has been widely used by Indigenous peoples across North America. Chippewa applied bark poultices to cuts; Abnaki used bark infusions as a vermifuge; Algonquin Tete-de-Boule applied root poultices for rheumatism. The stem bark is used in modern herbalism for rheumatism, arthritis, gout, urinary complaints, and fever reduction. German Commission E approved for haemorrhoids and wounds.
S28 30 drug/medicine uses; S29 salicylates, Commission E approval

✅ Edible

Foraging Notes: Inner bark (cambium) was scraped, dried, and ground into flour by numerous Indigenous peoples including Blackfoot, Apache, and Cree, often mixed with other flours for bread or used as a thickener. Sap can be tapped as a spring drink or flavoring. Catkins are edible raw or cooked but bitter. These are traditional and survival foods, not commonly eaten today.
S29 inner bark, sap, catkins; S28 12 food uses across multiple nations