Aira caryophyllea L.
silvery hair grass
Grey-green to reddish green, erect, slender, variable in height, consisting of a single delicate culm or a tuft of numerous culms; branching intravaginal. Leaf-sheath membranous to submembranous, ribs well-spaced, minutely scabrid above. Ligule 3-4.5-(6) mm, tapered, shortly denticulate, abaxially very sparsely scabrid. Leaf-blade 0.5-6-(12) cm × 0.5-1 mm diam., inrolled, ribs minutely scabrid; margins and subobtuse tip minutely scabrid. Culm internodes glabrous. Panicle 2-11 × 1-6 cm, ± ovate, lax; branches spreading, filiform, often flexuous, sparsely scabrid, naked at base with pedicelled spikelets clustered at tips. Spikelets silvery green or purplish. Glumes 1-(3)-nerved, shining, ovate-lanceolate, acute, keel sparsely scabrid, margins very finely ciliate-scabrid. Lemma firmly membranous and brownish below, colourless, hyaline, scabrid above; awn from lower ⅓ of lemma, projecting beyond glumes, column dark brown, twisted. Palea narrower than lemma, keels rounded, glabrous. Callus ringed by minute hairs. Rachilla minute, glabrous, not prolonged. Anthers 0.4-0.5-(0.6) mm. Caryopsis c. 1.5 × 0.4-0.5 mm.
