Flora of the Hawaiian Islands
Monocotyledon Literature for Aira caryophyllea
Wagner et al., 1990, 1999.
   Poaceae -- The Grass Family Bibliography
      Aira caryophyllea

Common name(s): hairgrass, silver hairgrass
General Information
DistributionNative to Europe, now widely naturalized.In the Hawaiian Islands, naturalized on Kaua`i, O`ahu, Moloka`i, Maui, Hawai`i.

Annuals; culms solitary or few, sometimes numerous, forming large perennial clumps resulting from reseeding, 3-40 cm tall.
Sheaths glabrous, open to base; ligule membranous, triangular, 4-5 mm long, apex entire but becoming lacerate; blades filiform or subsetaceous, usually 1-5 cm long, up to 1 mm wide.
Inflorescences paniculate, loose, ovate to oblong, 1-12 cm long, the branches bare at base; spikelets 2, ca. 3 mm long, clustered toward tips of capillary branches, pedicels 0.7-3.5 times as long as the spikelet and pear-shaped at apex; glumes pale brown, chartaceous, ovate, 2.3-3.5 mm long, enclosing the florets, nerves ± prominent, surface lustrous, glabrous except sparsely scabrous along keel, apex acute, slightly erose; lemmas dark reddish brown, narrowly ovate, 2-2.5 mm long, short-scabrous, apex acuminate, 2-lobed, apical teeth setaceous, awn 3-4 mm long, slightly geniculate, inserted below midpoint on dorsal face, rarely absent, callus minutely bearded at lateral margins of floret; palea similar in color, vestiture, and texture to lemma, 1.5-2 mm long, apex acuminate, somewhat adnate to caryopsis.
Caryopsis 1-1.5 mm long, ca. 0.5 mm in diameter, weakly adnate to lemma and palea and remaining enclosed within them.
2n = 14, 28