How to produce 'Birch Bark' ?

[76561198815743070]

I want Birch Bark for 20 pieces to upgrate Wood Workshop, but I don't know how to produce it.

[Panimo]

Hello,

Birch bark can be collected off of birks, they have a distinct look, i.e. they look different from other trees. I checked your account, it seems you found them; and some of the birches are ready for "harvest".

[76561198815743070]

Thank you! (\^0^/)