I just went to the corn field near Muldraugh to gather the corns while they are still fresh, and while it was one of the most rewarding tasks when it comes to the amount of food early game, looking for it was also one of the most boring (boring IRL that is) tasks to do in game.
A simple solution that would make looking for it easier and also would add somewhat realistic flavor to the game, would be to change tile's appearance for empty corn "containers" to look different to easily distinguish if the patch is empty or not, the same way how shelves currently do that.
The only real problem could be that once anything else is put in the patch "container" it would appear to regrowth, but maybe easy solution would be limiting the container capacity to 0, effectively allowing player to take things out but not allowing to put anything in (except for 0 weight items like cigaretters, unless their weight will get changed - which I think it should), something I suggested in another thread for dispenser machines
I realize that the current implementation of corn fields may be a placeholder and a more fine-tuned system to replace it is planned, but it would be nice to see this change quicker, especially as I think it wouldn't be so hard to implement.