Sculpted a dead tree I was able to print it without supports at .1mm layers not sure if it could print at .2mm without supports

I included the .blend file if you want to make variations very beginner friendly

Just move the vertex points around in EDIT MODE with G
Press E for a new branch
Control + R to add a point in the middle
press Control + A to enlarge points

To add extra details in SCULPTING MODE apply all modifiers
enable dynamic typology
constant detail = 40
Clay Strips brush