How to set _WaveAndDistance in the terrain shader

I see there is a field in the standard terrain detail shader that I'd like to tweak

Shader "Hidden/TerrainEngine/Details/BillboardWavingDoublePass" {
Properties {
_WavingTint ("Fade Color", Color) = (.7,.6,.5, 0)
_MainTex ("Base (RGB) Alpha (A)", 2D) = "white" {}
_WaveAndDistance ("Wave and distance", Vector) = (12, 3.6, 1, 1)
_Cutoff ("Cutoff", float) = 0.5
}

Is there any way to access the _WaveAndDistance property from script or inspector, other than by overriding the entire shader source?

 

It's in the terrain settings under wind.