You could take them to your local humane society-if they except wild animals. Luckily, the Wisconsin Humane Society-Milwaukee excepts wild animals. If they can be helped,they help them, then they release them. If they are extremely injured I believe they put them to sleep. My dad and I found a hen Mallard with a broken wing, they fixed the wing, and released her when she got better.

Wisconsin Humane Society -this is a pretty neat sight, if you'd like to check it out. (lots of cute pictures of puppies and kittens )

Maybe you could build/buy a nice cozy fully-enclosed bird nest box, and hope they might nest in that. Then hopefully, the babies can't fall out and they will be protected from the harsh summer elements and predators.