I am shucking some corn like a good appalachian gal for dinner and I'm always reminded of feed corn when I see ears of corn. Feed corn is tough and is what you feed your livestock.
When I lived at PeaceTree, a commune, we picked corn by the moonlight one evening. Our homegrown potatos were in abundance and we had them and tomatos for breakfast, lunch and dinner. Every single day. One night we saw a nice large corn field beside the road and thought that surely no one would mind if we snagged a few ears.
Back home and hungry, mouths watering, we cooked our corn over a fire and soon realized that indeed we had gotten feed corn. Damn. Hard, dark corn kernels welded into a corncob that a pig would refuse. Pass me another baked potato.