An experimental archeology study published in 2019 demonstrated how birch bark tar can be produced in an easier, more discoverable process. It involves directly burning birch bark under an overhanging rock surface in an open-air environment and collecting the tar that builds up on the rock.
An experimental archeology study published in 2019 demonstrated how birch bark tar can be produced in an easier, more discoverable process. It involves directly burning birch bark under an overhanging rock surface in an open-air environment and collecting the tar that builds up on the rock.