R is for Rocky Mountain Locust. The Rocky Mountain Locust is most famously known for a plague in the 1880's. The plague caused complete destruction to everything in the area. The Rocky Mountain Locust would eat everything in its way. This was horrible to a number of farmers, and they looked for a way to rid of the Rocky Mountain Locust. Which they have done successfully. No Rocky Mountain Locust has been seen in over fifty years.