Tufted Hairgrass

Deschampsia cespitosa

Pollinator Value

🐛 Larval Host: Thymelicus lineola (European Skipper)
S14 host record from Hesperiidae, established in ON/QC; S4 Poanes melane (Umber Skipper) western NA only
❄️ Winter Food Source: Seeds consumed by Mute Swan and Tundra Swan (Anatidae). Fruit/seed persistence is low, limiting winter availability, but dense tussocks provide cover structure for ground-nesting birds and overwintering invertebrates.
S57 Mute Swan (5% diet occurrence), Tundra Swan (2% diet occurrence); S11 Fruit/Seed Persistence=No; S64 nest site flagged

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 Ontario (S5). Not ranked in Quebec (SNR). Not listed under SARA or COSEWIC. Widespread across North America but locally uncommon in the Ottawa-Gatineau region, known from only three Ottawa sites.
S22 G5, S5 ON, SNR QC; S26 not SARA listed; S62 RS (3*) in Ottawa
Rarity Ranks: QC SNR – Not Ranked, ON S5 – Secure
Migration: Stable
Ecological Context: Tufted hairgrass inhabits wet meadows, fens, rocky lakeshores, and floodplains, typically on calcareous or marly substrates. In the Ottawa region it occurs at alvar sites (Panmure) and shoreline habitats (Shirleys Bay). Forms dense basal tussocks in open to semi-shaded wetland margins, often associated with Dasiphora fruticosa, Carex spp., and Parnassia glauca in rich fen communities.
S62 Ottawa sites; S7 Michigan habitats: fens, rocky shores, calcareous gravelly shores; S4 bogs, fens, sandy/rocky shores; S6 wet meadows

Roles: Fire Retardant, Fortress/Barrier, Pollinator Attractor
S73/S29/S72 Evidence: Fire Retardant: S73 [MEDIUM]: S11 Fire Tolerance = High (not definitional)] | Fortress/Barrier: S61 keyword match: prickl (supporting signal only)] | Pollinator Attractor: S73 [HIGH]: S64 Xerces listed (source-classified)]
Notes: Dense tussock-forming habit makes it effective for stabilizing wet soils and streambanks. Tolerates a wide range of light conditions from full shade to full sun, making it a versatile companion in riparian and fen restoration plantings alongside sedges and wet-meadow forbs.
S11 shade tolerance high; S4 fibrous root type; S7 associated with Dasiphora fruticosa, Carex crawei, Parnassia glauca

✅ Edible

Foraging Notes: Seeds of Deschampsia species were eaten by indigenous Californians. Not a commonly foraged species; the small grain size (USDA Small Grain=No) limits practical food use.
S4 Use Food; S11 Palatable Human=No, Small Grain=No