The Men of Mammoth Forest by Floyd Leslie Otter is a fascinating history of the men who lived and worked in California's great Sierra Nevada forests during the late 19th and early 20th centuries. Blending environmental history with human drama, Otter explores the lives of loggers, rangers, settlers, and visionaries whose ambitions shaped one of America's most majestic landscapes. Drawing on archival sources, personal accounts, and field knowledge, Otter reconstructs the rough-and-ready world of forest workers—men who endured isolation, harsh weather, and physical danger in pursuit of timber, grazing land, and new opportunities. Yet the book is more than a record of toil and industry. It also traces the beginnings of forest conservation, highlighting debates between exploitation and preservation as national parks and reserves were established. Through vivid storytelling, Otter introduces readers to colorful personalities: lumbermen whose saws echoed across the valleys, rangers who patrolled remote wildernesses, and community leaders who fought to balance progress with stewardship. Rich in historical detail, the book captures both the grandeur of the Sierra landscapes and the gritty realities of frontier livelihoods. The Men of Mammoth Forest remains an important contribution to Western history and environmental studies, a work that honors the resilience of those who worked the land while also acknowledging the costs of human ambition on fragile ecosystems.