The Seed Bank in Ft. Collins, officially known as the National Center for Genetic Resources Preservation, guards thousands of seed varieties. They're in a vault built to withstand attack, tornadoes and floods. It's part of a system of 20 seed banks run by the U.S. Department of Agriculture, and working with seed storage facilities around the world. The center stores the genetic raw material plant breeders will use to create new crop varieties to stand up to insects, climate change, other threats unknown today that might come along in the future. Dave Ellis is a plant physiologist at the Seed Bank. He talked with Colorado Public Radio's Mike Lamp.