I was able to confirm that this was intentionally done to harm sledders. I was up there the week before and a snow cat had turned around in this same spot, so I wasn't sure if that was being confused for the ditch. However, it looks like some people showed up on snow shoes and skis and did the work. 90 degree angle cuts with shovels and perhaps snow saw/chain saw (hypocrites). Anyway, I'm expecting an article in the Vail Daily this week. I also reported this to the Forest Service (VM) and have not heard back from them.