Cork......

[Justdroppedin]

https://thumbs.gfycat.com/ThoseYoungGrayling-size_restricted.gif

[dogdayz]

I thought that looks like a good way to kill the tree but apparently not.

Did some googling:
After each harvest the cork tree fully regenerates its bark and is harvested every 9 to 10 years until the tree is about 200 years old.

[runamok]

The cork they pull off will grow back.