Aira elegans Roem. & Schult.

Hairgrass

Aira_elegans_plant.jpg
STATS

Introduced
CC = *
CW = 5
MOC = 7

© DETenaglia

Family - Poaceae/Aveneae

Habit - Annual grass, forming delicate tufts.

Stems - To 40cm tall, erect, multiple from base, herbaceous, from fibrous roots, glabrous.

Leaves - Small, thin, to 5cm long, +/-1mm broad, scabrous. The ligule to 3mm tall, scarious, rounded at the apex. Leaf sheaths scabrous or glabrous.

Aira_elegans_ligule.jpg

© DETenaglia

Inflorescence - Fairly dense terminal panicles making up 1/3 to 1/2 of the plant height. Panicle branches ascending, glabrous. Stalks of individual spikelets to +1cm long, glabrous or scabrous.

Flowers - Spikelets to 3mm long, scabrous or glabrous. Only one lemma of the spikelet having an awn. Awns to 3mm long.

Aira_elegans_spikelet.jpg

© DETenaglia

Flowering - May - June.

Habitat - Prairies, riverbanks, disturbed sites, roadsides.

Origin - Native to Eurasia and Africa.

Other info. - This little grass is fairly uncommon in Missouri, being found in only a handful of southern counties. This is an easy species to ID in the field because of its small size, open panicles, and its single-awned spikelets. The inflorescence of mature plants is open and spreading with the pedicels of the spikelets being barely visible at a distance.
Another species, A. caryophyllea L., is similar but is smaller in size and has two awned lemmas per spikelet. This latter species is slightly more common in Missouri.

Photographs taken off Lee Rd 27, Auburn, AL., 5-4-05.