One of the Rust-Tex.blogspot.com readers came through my booth at Quilt Expo. She said her favorite thing on this blog is seeing the set-up and the resulting pieces. So here is a new set-up I developed that give me "birch bark" every time.
First picture is the gathered fabric smeared with "sludge", and dowsed in sumac juice and lightly salted.
Then beautiful results of white cloth with subtle lines of black and brown similar to the markings found on birch trees.
The side pillars at the top of this post shows how you might crop this fabric to REALLY make it look like birch trees.