Britannica Sources used in this answer

What is the function of a ligule on a grass leaf?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

wild rice — Poaceae Wild rice (*Zizania aquatica*).

In the context of the Poaceae family, the ligule is a small flange or ring of hairs located at the collar of the leaf—the junction where the leaf sheath meets the blade—on the side facing the stem.1

Its primary function is believed to be the prevention of water from entering the leaf sheath.1