Wow, quite the beautiful job on this. Quite surprised since most MC drawings on the pony groups are nudity for the sake of perviness, and is not well done..
No, this is quite beautifully done. Her anatomy is spot on, has that funny little censoring with the cattail, the coloring and shading are all amazingly done. I am blown away by the background as well, and love the blur done on the foreground, gives it a sense of depth. This shows great effort and skill.
Me, I'm not so sure? Outdoors if it was necessary and the situation required it? Certainly. Regularly? For some reason not so much...
...Fluttershy oddly enough, I could see doing this on a regular basis provided it was her alone with her animal friends. For all of her timidity she's very eccentric in a lot of ways and somehow I would see it fitting with her affinity for the animal world.