plume grass

Wiktionary

1. n. botany A kind of grass (Erianthus saccharoides) with the spikelets arranged in great silky plumes, growing in swamps in the Southern United States.
2. n. botany The still finer Erianthus Ravennae from the Mediterranean region. The name is sometimes extended to the whole genus.

GNU Webster's 1913

1. n. (Bot) The still finer Erianthus Ravennæ from the Mediterranean region. The name is sometimes extended to the whole genus.

WordNet 3.0

1. n. a reedlike grass of the genus Erianthus having large plumes