I recently bought a 50m roll of “Soft Flexi Plant Tie” from Bunnings.
Very handy for securing lights and cables to trees on a short term (seasonal) basis without damage.
Quite cheap at under $7 for the 50m roll.
Here it is used to hang the meteor tubes in one of my trees.
Easy enough to cut off (or untie for re-use) when the season is over.
Also good for attaching LED strings to palm trees.
Flexible enough not to dig into the trunk, but still holds in place.