Creating a staircase with roofs form

Hello everybody. I am modeling a spiral staircase. This should look more organic on the railing, just like art roots (you can see in the pictures). I first built the spiral staircase normally, but don’t know how I do, that kind of roots can be found on the site. Can someone help me there please? It Is for a project. I Upload my result and my reference picture-) Can I use the “unwind” command for the terrain and draw curves on it? and then simply wind it up again and delete the remaining area? and how do I manage that these roots are not vertical, but are also slightly bent? how do you do that with that command?