I like the last two shots, the sky in the second one is really nice. My only comment would be be that the grass looks over saturated, which has made it too green.
2nd is the most appealing to me except im left wondering where is the base of the tree? first one is over processed for my taste. The sky doesnt look real. The greens are a bit too saturated. The line of trees on the horizon appeals to me. I cant help thinking I have seen them before.