Question Change terrain trees during runtime?

We need to replace some terrain trees with alternate (seasons-specific) trees during runtime. Is there a way to do that? Unity terrain, BIRP, Unity 2020. ( We are already using Veg Studio Pro for higher graphics quality levels, which handles this easily, but need to do it for low quality levels which use terrain trees.)

thanks
Dave

 

I don't know if there is a proper way to replace the mesh, but a custom shader can probably toggle between various seasons with ease.