They both look better in b&w, and the looser crop on the second also improves it. I think you could get a little more drama out of them in the conversion, though. There is a lot of detail visible in the sky in the colour, which isn't making itself felt in the monochrome.
Jeremy
This is something I often struggle with.
The mood felt very peaceful (or maybe it was the jet lag) and that's what I was trying to convey and I don't always seriously consider different interpretations that might fit the image better than my initial impression.
Here are a couple more versions, one with a focus on the mood and the other on drama. I do have a tighter frame with more focus on the tree but I felt the more menacing/unfriendly rocks around it accentuate its survival drama.
PS. the way I thought this is drama on one hand, a small tree surviving where you would not expect it, and yet a soft, peaceful light on the other. Hence my difficulty to convey both, should that be even the right choice. Usually I don't put that much thought into this but this one stroke a chord.