Ther is a substance called Diatamaceous Earth. It is used in food storage to keep out all pests. It is a white powder, and you can use it on garden plants to keep bugs off. You can put it on pets to keep pests off. It is supposed to even kill roaches. It is food grade , and not harmful to people.
Walter, stored brown rice becomes rancid if not frozen or vacuum packed and kept dark and cool. White rice lasts far longer. Beans and dried corn are good keepers. For long-term upheaval/unrest/whatever, think of storing ingredients instead of packaged goods. Dry pasta keeps well..
Everyone, check out the survivalmom.com. She's great.