 The immigrants soon discovered, however, that the climate in the Colorado mountains was only suitable for growing crops for less than four months out of the year, and the first frost of winter killed most of what was still planted in the fields.This failed season of crops forced the immigrants to look for jobs elsewhere to help pay off their fast-growing debt to the local store.They soon found work with the Denver and Rio Grande Railroad which had decided to lay down more tracks to the west over Marshall Pass.