Aint no belly mower yard tractor gonna cut head high weeds and/or an overgrown field in the woods!

I agree, spray it first & rent or pay a bud with a bush hog to go in & cut it all up good for you.

If it's been a dormant field/opening for years then whatever you can pull with a mower or even an ATC aint gonna be heavy enough to properly cut that ground under. If you arent going to rent/borrow the appropriate equipment then you might be $ & time ahead to consider some no-till plot mixtures.