Hi snaglpus,
If setup correctly, those help.
The problem is that wind will blow through and will untie it if not properly secured. That done, it will rub and rub on the tree and that will wound the tree.
So first tie the branches of the tree to its center and then apply the cover.
Other problem, if your tree is a bit too big, how would you protect it ? Are roots more important than the canopy ? Or canopy more ?
Good luck.
I prefer use big bags - some neighbors used some unused dark trash bags
PS: if snow or water+frost comes in, do not forget to check and remove the snow/ice that stays on the cover, to avoid overweight problems on the canopy. Or the branches may break.