Vetiver grass is used both as a hedge against erosion in permaculture colonies, and also a medicinal herb! It forms narrow, dense hedges when planted along the contours of sloping land, slowing down run-off and helping the water soak into the soil rather than washing off the slope. The stiff foliage also blocks the passage of soil and debris which gradually builds up a soil terrace. It’s roots yield an aromatic and medicinal essential oil, it sequesters excess atmospheric carbon, and Vetiver mulch is mycorrhizal-rich.
Check out this amazing article about how Vetiver is used around the world to restore the land. Here is an entire podcast devoted to the many uses of this amazing plant!