There is no such thing as local. Apples are from Asia. Corn comes from South America. Potatoes originated in the Andes.
All life seems to be on an endless journey to trade one side of the globe for another. Especially the delicious, nutritious and overall most productive species.
To ask the question, what is local, one must be prepared to trace backstory beyond backstory. An exhaustive and easy to abandon sort of adventure. Still, rife with rewards.
In the actual locale which inspired and wildly cultivated the feral potato, it was poisonous. In the same family as Belladonna. Otherwise known as Deadly Nightshade. The journey here ends in a popular, palatable, hearty root, but begins with a toxic tuber buried just beneath rock-laced ground.
Fine sweet yellow and white corn, so clean, plain and simple, was once inspiringly colorful. And the further south and slightly west you go, ancestors of our too-sweet summer crop still grow traceable back through their roots to grass. Corn is a kind of grass. Consider that next time it takes an afternoon to level the lawn.
For the most part local, and what quality the term might suggest, is an idea. A hopeful, albeit often fruitful, thought. Sort of directional, like a compass-bearing. And what is north or south really? A vague distance to face head on, pursue, with all the lessons and encounters and mountains along the way unknown, unimaginable. It is not the destination, but a direction, like east or west. There is no single answer to the question where did all this food come from.
Because true local is not a place. It is the quest.