Trevor Warmedahl's new book, Cheese Trekking: How Microbes, Landscapes, Livestock, and Human Cultures Shape Terroir, documents natural cheesemaking practices in traditional communities. Warmedahl is a cheesemaker, educator, and founder of the Sour Milk School, where he teaches natural methods of milk fermentation suitable for the home, farm, restaurant, or commercial operation. The book recounts his travels to Mongolia, India, Norway, Italy, Austria, Slovenia, Georgia, and Spain, where he met cheesemakers using practices that go back generations and result in cheeses with flavor and "terroir" far beyond anything he'd ever encountered. And the pastoralists who make them have deep connections to their land and animals, and are doing a kind of agriculture that heals the land and promotes biodiversity.