Hi Hendo64 and welcome to the forum,
Yes, you would need climbing sticks or tree spikes to use the tree saddle. Depending upon where you hunt, this decision can be made for you. I hunt public land and the regs don't allow for screw in tree steps, so it's climbing sticks for me. I'm leaning toward lone wolf brand due to their light weight, about 10 - 12 pounds for 4 sections.
As far as the tree saddle, it like a mountain climbing harness that you secure to the tree.