Interesting that Ivorybill mentions possibly getting in touch with someone at Michigan State, as I figured I would mention checking out your local Master Gardner program, which is run via the Michigan State University Extension. While I’m not familiar with the Michigan program, the ones in Oklahoma and here in Texas are incredibly knowledgeable about native flora and what grows best in the area.
Heh, remember, I’m in the UP, not Michigan. Michigan State University is 400 miles and 2 hardiness zones south of me.
That said, I know a few master gardeners up here, but they look in horror at my yard and run screaming. I’m having a hard time convincing them that dandelions are flowers, not weeds. 
Yes, but they’ll still know more than the folks in Ann Arbor… Not that I have a dog in that fight - - Michigan’s forestry school is at State & they’re likely to know a thing or two about your situation, even though they’re trolls. FWIW, my recently retired boss, originally from Escanaba, has three forestry degrees from State.
Well, I’m sure you’re joking, but just to be pedantic, every county except Keweenaw has an MSU Extension and along with it a Master Gardener program.
Roundup is just nasty stuff.
I would vote for hiring a local farmer with a mega rototiller on back of his tractor to till up a chunk of your property and buy a buttload of wild flower seed mix. Not those shaker cans available at all Walmarts. But something like a 5# bag of everything, mix it in with some sand in a seed spreader and then water regularly.
I did this a few years ago to a portion of our front lawn ( not visible from the road) and it was wonderful. Every few years you have to burn it back to re-charge the soil or something. It is now back to its original state of overgrown weeds.
The seed is not cheap, however. I used a company somewhere in Indiana that was the best rate I could find for like a 10# bag of wild flower seed mix. It was about $100 or more.
Buy a slip and slide. That always worked when I was a kid. You can kill it one 3ft by 10ft section at a time. And the neighborhood kids will love you. 