Anthoxanthum

In a revision of Anthoxanthum in Malesia and Thailand, Schouten & Veldkamp (1985) unite Hierochloë with Anthoxanthum, based on intergradation of characters used to separate the two. Consensus on uniting these two is building, and we here follow that trend. 

1. Panicle open, pyramidal, the branches spreading or drooping; glumes nearly equal in length, with lateral nerves obscure or prominent only on basal half; lower florets awnless.

A. hirtum

1. Panicle contracted, the branches ascending or appressed (the lower ones sometimes spreading-ascending only during flowering); glumes very unequal, with lateral nerves (at least on larger glumes) prominent beyond the middle; lower florets awned.

A. odoratum