Very nice form and texture. But to me, they need more contrast to bring the wood of the bridges out so they aren't lost amoung the grass. One or more of them might even benifit by over doing the contrast to bring out the lines and texture of the wood.
Wow, I definitely like #1 the best. The lines really lead your eye everywhere. Also, the contrast is great. You could possibly size it down for the message board so I dont have to scroll down the see the entire picture