I was trimming the new growth of my large Japanese maple last night when I came across the below pictured damage to the bark/trunk. See third photo. I am pretty pissed off as I have no idea as to the cause or what I could do to prevent this sort of injury in the future. It is discouraging from a bonsai enthusiast's prospective that years and years of meticulous work could be spent to grow high quality nebari, scar free trunks and quality branching structure only to have it randomly damaged and decreased in quality like this. I have only had this particular tree for 10 months, but this thought about keeping quality bonsai in the future remains. Btw, I am going to be removing the funky wire soon!