1	"Lemma with retorse apical prickles"	"Orthoraphium {Orthoraphium roylei}"
1	"Lemma without retrorse apical prickles"	2
2	"Lemma lobes awn-like, 2-3 mm long"	"Trikeraia {Trikeraia hookeri}"
2	"Lemma without awn-like lobes, if present, lobes flat andshorter than 1 mm long"	3
3	"Awns straight, scabrous; anthecia usually dorsally compressed; calluses up to 0.3 mm long"	Piptatherum
3	"Awns geniculate, scabrous or variously pilose; anthecia not or laterally compressed; calluses longer than 0.3 mm"	4
4	"Calluses longer than 0.9 mm; lemma epidermes with numerous minute hooks (visible under high magnification)"	Stipa
4	"Calluses up to 0.8 mm long; lemma epidermes usually smooth, rarely with infrequent minute hooks"	5
5	"Lowest segment of awns pilose, hairs over 0.3 mm long; lemma epidermes with elongated fundamental cells (4-11 times longer than wider) and occasional silica bodies having 1-3 constrictions"	Ptilagrostis
5	"Lowest segment of awns scabrous, hairs up to 0.1 mm long; lemma epidermes fundamental cells at least as wide as long, sometimes long, silica bodies rounded, with 0-1 constrictions"	Achnatherum