Hi,
thank you for all your comment's.
@Kerry
The birch and pine tree trunk are made of copper wire primed with "HEKI Straßenfarbe" and silica sand. Then painted with Revell acrylic paint. The foliage is from MiniNatur (Scale 1:87). You will find it
here.
If you want to know how to build the trunk, you will find a german speaking tutorial
here. But it is excellent documented with pics.
regards
marjac