Agrostis
Perennials, rarely annuals, caespitose, rhizomatous or stoloniferous. Spikelets generally less than 7 mm long, without a rachilla extension. Glumes generally longer than the flower, with one vein, their apices acute to acuminate, muticous or rarely awned. Callus of flower glabrous or with straight hairs less than ½the length of the lemma. Lemma generally hyaline or thinly membranous, with 3 or 5 veins, the apex truncate or toothed, awned from the apex or more often abaxially, the awn straight or geniculate. Palea generally minute or lacking. Fruit with endosperm hard, soft or liquid. 2n ¼ 14, 28, 35, 42, 56. Two hundred sixty-four spp., worldwide in temperate regions. Agrostis intergrades morphologically with Calamagrostis, but Saarela et al. (2010) find that most species of Agrostis form a reasonably wellsupported clade, distinct from Calamagrostis. Chaetopogon falls within Agrostis in the trees of Saarela et al. (2010) and the morphology is fully compatible with including the former in the latter genus.