It is cut into the inner side of a white oak wine barrel head.
The coloring is from years of contact with red wine.
I used a 1/8" two flute end mill for the pocket cut around the tree with a 1/16" 4 flute end mill for the finishing pass and a 1/2" V-bit for all of the lettering.
The barrel head is not flat or level so it was a bit of a challenge to find a good Zero for the Z-Axis.
There is about 1/8" between the thinnest board and the thickest one.
In the end I used the thinnest board. (the one just right of center) for my zero.
The board with the "EST." carved into it is one of the thicker boards but the wine really soaked into it so it looks shallow.
I plan to coat it with a wax based UV protective coating.