Tidbit: Basic survival garden items

I viewed an interesting little 8 minute video on YOU-Tube today that talked about 4 basic survival garden plants. http://www.youtube.com/watch?v=hIdzmIn79UE&feature=player_embedded
Scott, I think his name was, from the Living History School...

There are 4 basic survival garden items.  These items are not part of a typical "salad garden".   The salad garden would be lettuce, tomatoes, carrots, etc.  The survival garden would contain, potatoes, corn, beans and squash.  The survivalists say that these 4 foods can continue to grow for several days without water and attention.  They are the basic foods that the pioneers and Indians grew for their survival.  When growing these "survival" foods we need to know how to grow them, seed them and process them correctly for winter storage.  Their seeds can be saved until the next growing season to use for the next years crop.  These foods can also be planted together in the same space, as each one uses and gives back different nutrients to the soil.  The corn is planted first in a mound.  Then the beans are planted around it and can grow up the stocks.  The squash can be planted around that and the large leaves keep the warmth and moisture in the soil.  The Irish have survived on potatoes for centuries.