Tried using an enchanted spell turret and a timer spell turret to cut a tree down. I tried using oak, acacia, and spruce for the tree, but the spell turret couldn't even break the base of the tree, much less cut down a whole tree.

Originally, I tried touch > fell > AOE x2 with the spell parchment onto the turret but it didn't work, so I tried increasing the AOE to x8 and it still didn't work.

I tried casting touch > fell > AOE x2 and touch > fell > AOE x8 spells from my spell book and it worked just fine.

minecraft version 1.16.5

ars nouveau version 1.23.11

This is likely because you are on a claimed chunk of some kind, either FTB or Minecolonies. You need to add Minecraft and potentially ArsNouveau as an ally to those in order to allow turrets to break blocks.