It's used to stabilise soil against erosion.

I'm experimenting with planting it around young fruit trees to provide shelter & mulch as they establish. The roots go straight down up to 20ft and mine nutrients without competing with fruit trees that have shallower root systems.

I'm also planting it on & in my new water channels (they're not really swales).

They can be planted on contour to filter runoff of soil and will over time create biological terraces. The vetiver will grow up the terrace as more soil is deposited.

Vetiver is sterile & non invasive. You propogate by splitting clumps into slips and planting. 

 I planted about 6500 of them on my sloped property to protect against erosion.  I was just curious how you were using them.  I didn't know about water channels.  what purpose does it serve? strictly for erosion or are you using the water? 

 It's essentially diverting a seasonal creek to a less productive area of my land.

I would have done things differently with hindsight but I found vetiver after I dug it all out. 

 that's a great idea, better than concrete