Obviously working the soil is best....however, you can have a great food plot without working the soil.......it's call the no till over seeding method. if I am working on areas where I cannot get a tractor into I do this....
spray 3-4x over the summer with gly
Once everything is dead broadcast several hundred pds of pellet lime and fertilizer
Overseed (broadcast onto bare dirt) rye, oats, winter wheat and clover before a rain (rye, wheat and clover do best)
You can also do this with brassicas
Some of my overseeding plots turn out just as good or better than the plots I till. One advantage you have by not working the soil are weeds. You don't bring up new weed seed.
Plant winter rye and clover from mid-august to Sept 1.
Attached is a pic of an overseed plot I did on a gasline on the Northern end of my property. This was before I amended the soil with lime and fert. Notice the green carpet. I get even better results now. That's the one thing about rye I love....the deer love it and it grows about anywhere. This particular plot is tough to get to with a tractor so I use this method every year.