If you want to see, you have to Look.
I thought it was moss on tree bark until I read the words. Totally fooled me. You are quite right about context. What a photographer includes or excludes can dramatically alter the impact of the photograph. Interestingly I wrote along similar lines (but with regards to architecture instead of rocks and moss) earlier today.
This does have a certain abstract quality. It's effective in color but I'm wondering if it would be more so in black and white. I think that removes some of the context, though.