Aira praecox L.
early hairgrass (yellow hairgrass)
Poaceae (Grass family)

Introduction to Vascular Plants


© Jamie Fenneman     (Photo ID #29440)


E-Flora BC Static Map

Distribution of Aira praecox
Click here to view the full interactive map and legend

Species Information

Annual, tufted, smooth or more or less rough short-hairy grass from fibrous roots; stems 1 to several, slender, delicate, hollow, 2-12 (20) cm tall.
Sheaths open; blades scarcely 0.5 mm wide, threadlike, in-rolled; ligules 1-3 mm long, pointed to blunt, slightly jagged tips.
Inflorescence a compact, congested and almost continuous, more or less spikelike panicle, mostly 1-3 cm long, the branches erect; spikelet stalks shorter than the spikelets; glumes (2.7) 3-3.2 (3.5) mm long; lemmas (2.5) 3-3.2 (3.5) mm long, usually lightly rough short-hairy, awned, the awns 2-3 mm long; anthers about 0.2 mm long.

SourceThe Illustrated Flora of British Columbia


If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.


Ecological Framework for Aira praecox

The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)

Site Information
Value / Class




Elevation (metres)
281 0 2100
Slope Gradient (%)
38 0 120

Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]

135 10 360
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
1 0 6
Modal Nutrient Regime
# of field plots
 species was recorded in:
Modal BEC Zone Class

All BEC Zones (# of stations/zone) species was recorded in

CDF(32), CWH(18), ICH(2), MS(1)

Habitat and Range

Vernally moist to dry gravelly or rocky bluffs and grassy meadows; common on S Vancouver Island, the Gulf Islands and lower mainland, infrequent N to the Queen Charlotte Islands; introduced from Europe.

SourceThe Illustrated Flora of British Columbia


Synonyms and Alternate Names:
Aspris praecox (L.) Nash