I've mentioned Jerusalem artichokes, or sunchokes before. This survival food fed the French under nazi occupation. Their grains, fruits and veggie production were all used for German troop and civilian consumption. If not all at least a very large portion.

The French though had this low- to-zero maintenance staple food crop that they could tend in private. It can be invasive, so don't plant in the garden. Plant random plots out in the wild like deer food plots. Keep a map that designates these spots. You could add to this acorn and walnut stands, cat tails, asperagus stands.... A survival food map.