I can’t tell you all about this as I don’t know what it is. It has been put there for a reason and has a number on one end. What looks like a wire in the picture is actually a cable tie. I’m guessing it’s something to with wild life.
I’m sure someone will recognise it!!
Are they going to cut that tree or the brush out of this area and that's a marker for the trimming crew? Seems strange to have plastic casing around a numbered piece of wood with a zip tie attaching it to a tree for no apparent reason. It would be a rather bizarre art piece!