Using only Antwerp blue the entire background area with the exception of the center tree was painted with a light wash.

Each layer was built up by adding a little more pigment to the wash to darken it and leaving a few more trees.
Each layer leaves the original trees untouched and leaving smaller and darker trees.
The painting was left to dry and using pure pigment with a small amount of water the "whip" marks were painted into the background birch trees as well as the smaller branches on the trees.
I will post this piece at a later date as more of it is completed.