How to fight a lawn on both sides when planting a hedgerow?

Hello! I posted recently about deer control on a hedgerow project that I’m starting in the upper peninsula of Michigan, and now I’m coming back to ask for more advice on the same project. This time, I’m looking for advice on how to deal with the lawn.

After considering advice from my last post, I have decided that the best course of action to start my hedgerow project is to enclose the entire planting area in 6 feet of fencing with a depth of 6 feet between walls for two rows (or more) of native plants. (if you think I should opt for taller fencing or a narrower channel, please let me know.) I will be planting hazelnut bushes, elderberry, blackberries, choke cherries, American plums, and similar plants suited for the cold-hardy forest of Michigan’s upper peninsula.

I am now concerned about fighting the lawn. The area is not sheet mulched. The soil is extremely hard from years of being a lawn. It is also sandy and very well drained. While I will be throwing cardboard and organic matter on the hedgerow in the summer and fall, I’m looking for advice on the best way to deal with the lawn over the course of the summer. Because most of the hedgerow gets good light, I am thinking of buying or renting an electric tiller and tilling the whole hedgerow plot. I will then dig a slight channel through the center of the hedgerow to mound the soil on both sides to create a further barrier to grass. I will plant the trees along both mounds, and when it warms a few weeks later I will weed or maybe even till again between trees and plants corns beans and squash on the mounds in between the trees. In particular, I’m planning on getting a lot of gete okosomin squash seeds to plant and use as a living mulch. From what I’ve read, those squash should do quite well with the low GDD on the peninsula.

That is my candidate idea. Does anyone have any thoughts on that idea or any advice? I wanted to plant some annuals this year but didn’t think I would have time to do so until I realized I could use the annuals to form a kind of barrier against the grass and serve the hedgerow as well, killing two birds with one stone. Tilling for this first year to reset the lawn a little feels kind of right as the ground is super compacted from years of being a lawn. Eventually this area will all be mulched and closed canopy, but I’m looking for advice on how to get there.