Im sure you have all heard of these concepts before. Im just throwing my vote in for a multi tiered gardening approach. Find a range of plants that can take care of themselves in your area, including longer term solutions like trees. If there are choices which cover all of the bases in my arid area, with a short cool growing season, I am sure there are most anywhere else. A little research, a little time, and the right seeds, can make all the difference in the world.
http://www.redwoods.quik.com/webteck/george/legumes.htmlhttp://www.ancientcerealgrains.org/seedandliteraturecatalog1.htmlI didnt see these on the list.....
the top one has a good amount of edibles, you could likely establish "wild" if you had some space. some other interesting things also.
The bottom one is a company called Kusa, they have collected alot of the ancient grains, along with many others. For nearly every area there is likely grains you could grow if you had the space, with less input then modern varieties in many cases.....
I especially like the "miracle" barley seeds offer. They relate a story of a plant breeder in india, who bred these barleys. As productive as the green revolution crops, yet produced with very little water, on poor soils, and many even had higher amounts of lysine rare for barley. as soon as the project proved a success his work was destroyed besides a few ascensions he sent to Kusa. I highly recommend them. They will grow on poor soils, without extra water for most people, a few as little as 90 days, healthy, versatile, also dwarf stature, much shorter then most grains.
they give you a small amount it would take awhile to save up enough for a large planting, but personally I think its great. If you dont have irrigation and are forced to grow your own grains, this would be a good one to have in the mix basically. Barley is self fertile by the way, so you could get a little patch each year of these and enlarge it each year, growing them close by with no issues. Within a year or two, I might have seed to give people......
as far as I see it, I believe in redundancy, if you have the space, set up a garden you manage, and properly store the produce of. but also get various types of fruits, and berries, and nut trees going..... sure that is longer term thinking, but that might very well be what we need. Under the trees establish wild edibles, that you could tend by weeding out the non edibles, and spreading the seeds of the ones you like the most. there are greens both perennial and annual that in most areas , could be growing wild or near it...... there are "grains" like indian ricegrass and sand dropseed, very drought tolerant, could be established about anywhere, and is healthy. Plus not likely anyone else would think it was anything other then some bunch grasses. Now tht I think of it the link below has those grasses....
http://plantsofthesouthwest.com/ 
