I am in Oklahoma, which has extreme temperatures throughout the year. The summer will be 95 degrees on average and very humid. I have a bermuda lawn that is very thin and has very shady spots around the trees, house and flowerbeds(bermuda will not grow in the shade). I want to seed the lawn, or at least the shady areas in order to have lush grass throughout the entire lawn. What is my best option? I have looked at many fescues, ryegrasses, and blends, please help!