Aira L.
Spikelets 2–3 mm long, with 2 florets. Pedicels and branches thread-like and delicate Aira
Panicle open. Pedicels as long as or longer than the spikelets
Pedicels twice as long or longer than the spikelets
Spikelets c. 3.5 mm long, mostly with 1 exserted awn. Pedicels mostly 4–6 times as long as the spikelets with clavate swelling below the spikelets. Erect annual up to 35 cm high. Blue Mts Introd. from Europe. Fl. summer Aira provincialis
Spikelets 1–2.5 mm long, with one or 2 exserted awns. Pedicels 2–5 times as long as spikelets, without clavate swelling. Erect annual to 50 cm high. Blue Mts Introd. from Europe. Fl. summer Aira elegantissima