I have found several chests that are covered in brambles. I have tried to hit them with everything in my inventory and it doesn't make them go away. Considering Kratos was able to throw an entire tree around he should really be able to tear these off with his baby finger! How do you clear the brambles from the chest?
I can't give you the exact answer without a big spoiler. Once you obtain the means to clear he brambles from chests you will be shown. The game will give you a sort of tutorial and you will need to clear some brambles to get out of where you are. After this point you will have an item that can do what you need.