I'll just say that, in my opinion, you nailed #1! You've got a good defined subject which otherwise could have easily been lost in the similarly colored grass, you've got a beautifully done sky, and the trees are all done great with minimal halo. To put it shortly, its a keeper!
Now, as for #2 and #3, those don't quite ride in the same boat. #2 is a bit flat in my opinion, and while the creek makes for an interesting leading line, I just can't love the photo anywhere the same way I do #1. #3 is just "meh." I see the effect you were going for, but I really don't think it works well, or that you would have needed HDR to accomplish such a look. Now that I think about it, the same goes for #2. The only photo that really demonstrates a good reason to apply HDR is #1.
P.S: I just remembered though that you may want to move these into an HDR gallery, or perhaps a landscape one, in order to get more specialized CC. This is the wildlife gallery
#1's HDR I feel is a tad overdone, but the sky looks decent and like togalive said, you have separated the bench well from the surrounding color of the grass. #2 in my opinion wins for composition, and #3 is a bit crowded, but I get what you were trying to do here. This is only my opinion, and the original images must have looked great on their own. # 2 does it for me, but maybe because I grew up in the fields of the wheatbowl and am used to vast spaces of nothing with the occasional small body of water.