The Community of Disc Golfers and About All Things Disc Golf
Galvanized. Won't rust.
From a tree huggers viewpoint, please don't drive nails or screws into a tree please. Adjustable zip ties work well if the tree is young and still growing. If it is a mature tree, use plumbers band hangers to strap it to the tree.
If you are going to nail it, use copper nails, that'll kill the tree for sure and clear the mando out of the way. hehehe
Hopefully it will be respected and not vandalized!