Spikelets articulated on their pedicels below the glumes and falling away at maturity; usually 2-flowered, the upper flower perfect and producing seed, the lower flower always male; rhachilla not continued beyond the upper flower.
Tribe 1.
AndropogoneÆ.
Spikelets usually 1-flowered, generally in pairs, rarely in threes or solitary, on the rhachis of a spike or branches of a panicle, all hermaphrodite or some of them male, in the latter case so placed that a male spikelet stands by the side of a hermaphrodite one. Flowering glumes hyaline, often awned, usually much smaller than the empty ones.
Panicle long, dense, cylindrical. Spikelets awnless, almost concealed by long silky hairs |
1.
Imperata. |
Tribe II.
Zoysieæ.
Spikelets usually 1-flowered, solitary or in clusters on the rhachis of a spike or raceme. Flowering glumes membranous, never awned, usually smaller than the outer glumes.
Small creeping usually maritime grass. Leaves short, rigid. Spike short, stiff. Spikelets appressed to the rhachis |
2.
Zoysia. |
Tribe III.
Paniceæ.
Spikelets with 1 terminal hermaphrodite flower with or without a male one below it. Flowering glumes awnless, cartilaginous or coriaceous, in fruit hardened and enclosing the grain. Outer glumes thinner in texture than the flowering glumes, rarely awned.
Spikelets 1-flowered, plano-convex, sessile in 2 or 4 rows in one-sided spikes which are either in pairs or form the branches of a simple panicle. Empty glumes 2 |
3.
Paspalum. |
Spikelets with 2 hermaphrodite flowers, panicled; outer glumes 2, persistent after the rest of the spikelet has fallen away |
4.
Isachne. |
Spikelets with 1 hermaphrodite flower and sometimes a male flower below; outer glumes 2 or 3, not awned, the lowest often very small |
5.
Panicum. |
Stems weak, decumbent; leaves broad, ovate to lanceolate. Spikelets as in
Panicum, but outer glumes awned |
6.
Oplismenus. |
Spikelets enclosed, each one or 2–3 together, in an involucre of rigid spines or bristles, often connate into a cup below |
7.
Cenchrus. |
Stout wide-creeping sand-plant. Inflorescence diæcious; males in spikes clustered in heads; females in dense globular heads with long radiating pungent-pointed bracts |
8.
Spinifex. |