buttongrass

Noun

button grass (uncountable)

1. (Australia) Any of several grasses with round or globular flower heads; especially Gymnoschoenus sphaerocephalus, a tussock-forming sedge especially of western Tasmania, forming distinct plains; and Dactyloctenium radulans, an annual grass of mainland Australia.
   • [T]he ceiling swelled in waves like an ocean, like a buttongrass plain, like the pocked earth stripped of its trees […].1997, Richard Flanagan, chapter 75, in The Sound of One Hand Clapping, New York: Atlantic Monthly Press, pages 377–378