This grass is somewhat rare in England. The jointed basal awn, with a minute hair-tuft above the middle, is unique, and readily distinguishes it when mixed with Agrostis.
⊙⊙ Awn not bearded or thickened.
≡ Palea bifid at apex.
Aira caryophyllea.
A. præcox.
|
Aira caryophyllea. A. præcox. |
Aira caryophyllea, L.
"Seed" 1·4-1·6 mm., comma-shaped and dark-brown.
Palea acute, nerveless, inrolled at edges and with a dorsal, kneed, very fine, dark twisted awn twice as long as the palea: the latter with two-toothed apex and a basal hair-tuft.
A common impurity in commercial seed.
Aira præcox, L. is very similar, and cannot be distinguished with certainty by the “seed," but has a shorter awn and no basal hairs. Apex of palea two-toothed.
≡ ≡ Palea jagged or toothed, but not bifid.
Aira flexuosa.
A. cæspitosa.
| Aira flexuosa. A. cæspitosa. |
Aira flexuosa, L. (Fig. [70]).
Palea 5 mm. long, four-toothed at the apex, and caryopsis 2·6 mm. The fine basal awn waved or kneed, about twice as long as the palea. Fruit with a groove.