The Diagonal challenge is full of irritating tilted horizons - but here is one that is fully justified! This is just as I remember feeling as I rolled my car over a few years ago - scary stuff, and you have brought it all back!
I like the angle and crop. And idea. Details in the shadows are lost, though. Perhaps most of all, apart from the angle, there is no sense of movement in the picture, which I guess you were trying to convey.
Nice photo. I like the angle, as it turns a normal landscape into an action shot. The grass colouring looks oddly uniform - was it genuinely that colour?