I like this post a lot. :D A wise choice to use a slower shutter speed on the waterfall. And the little rock with the moss! I like the first picture better than others you've done of similar looking flowers in black and white, simply because I think keeping the colors lets the character of this particular flower reflect more, since it's not as dramatic as a rose or something like that. The use of aperature in the tree/bobble one is masterful. I'd like to see the last one darkened a bit to give it even more depth, but maybe that's personal taste.