It is nearly impossible to establish native plants in turf grass. Also, the "meadow" could be many different things. The meadow might be full of exotics itself or it might be real native stuff or a mixture of all of these. Either way, you would probably get much faster and more reliable results if you killed the turf and edged or trenched where the remaining turf borders so that the meadow can creep in and the turf can be kept out.

Thank you Bob. What do you think would happen if I just let the turf grow up? Will that give the effect of a "sea" of grasses, or will it die do you think?

You'd probably have a lot of tall turf grass. I doubt it would die but it might go dormant and brown once in a while.

You need to get a book on growing native plants, and it will give you good details on establishing a real native meadow/prairie. see some books i recommend. You need to do your research before you start, and really plan it out.

it sounds simple to just let the grass grow, but the species you have in your lawn won't just quit growing and be replaced by more desirables without a little help. and the best thing is to just do a little at a time, dont try to do it all at once and get discouraged.

Here is a link that might be useful: books i recommend