The US Forest Service Avalanche Handbook (Agricultural Handbook 489) by Ronald I. Perla and M. Martinelli, Jr. is the authoritative guide to understanding, forecasting, and managing avalanches in mountain environments. Developed by the USDA Forest Service’s Alpine Snow and Avalanche Research Project, it covers the science of snowpack stability, avalanche formation and types, weather influences, terrain analysis, and practical field techniques for observation, prediction, and control. The handbook includes clear explanations, diagrams, and methods used by snow rangers, ski patrollers, mountaineers, and rescue teams to assess risk and respond effectively. Written in a straightforward, technical style, it serves as both an educational resource and a field reference for safe travel and operations in avalanche-prone areas. It emphasizes evidence-based approaches drawn from research and real-world experience in the Rockies and other ranges. I have to admit, as someone who lives so close to the Rockies, I’ve been hesitant to let this one go. It does have wear on the outside cover, some of the edges are rounded, and it’s best on a shelf between two other books. There is a page section in the middle that is still attached, but not fully, and handling this book too much may cause them to fall out.