Q.What Nitrogen-Fixer Will Out Compete Grass?
I live in a windy, semi-arid location. I have a big lawn of hardy grass. I want to replace much of it with organic food production. I have dug up areas of grass, planted natives and laid carpet down around them, but the grass keeps growing back. Are there any nitrogen fixing plants which might help me beat back the grass? If not nitrogen fixing, then what other plants might help?

Certified GKH Gardening Expert
White clover might work for you. This article will help:
https://www.gardeningknowhow.com/lawn-care/lawn-substitutes/white-clover/grow-a-white-clover-lawn.htm