If the volcano erupts in Yellow Stone, or California falls into the ocean or society breaks down for some other reason, Barbara Kingsolver and her family might just be okay on their farm in southern VA. Barring physical attack, they will be safe and have enough to eat because they grow it themselves. Kingsolver's book chronicles "One Year in Food Life," meaning, they ate only local food for one year. There were a few exceptions to this rule: coffee, some spices, whole wheat flour. Otherwise if it didn't grow on their farm or a neighbor's farm, they didn't eat it. This meant they had to can and freeze their crops for the winter. They also raised poultry and then harvested it (i.e. slaughtered, de-feathered, gutted, washed and froze it--the way she wrote about it was amazing, seriously, you should read it for yourself). Their chickens gave them eggs enough to eat and sell, her youngest daughter's project. They made their own cheese from store bought milk (not sure if it was locally sourced, it may have been an exception).
At times I was a little annoyed with the "journalistic investigation" tangents and was more interested in the memoir portions, especially the farming. Do you know how asparagus grows and is harvested? Now I do and it's fascinating. I never thought I'd enjoy reading about a plant growing, but it's wonderful! Go find out for yourself.