Following his acclaimed guides to air, fire, and water, David Carle now offers a fascinating exploration of one more primary element of the natural world - the land beneath our feet. From earthworms and earthquakes to Earth Day, this concise, engaging guide is a multifaceted primer on the literal foundation of California's environment. Carle tells how soil ecosystems function, discusses what lives in the soil, and examines various soil types. He then turns to the relationship between humans and the land, and investigates the various uses and abuses that land in California endures: large scale agriculture, mining, and development, as well as fires, floods, and erosion. The guide also details the history of land use in the state, making it an essential resource for understanding our total reliance on soil, the marvelous substrate that is the basis of life. It covers the entire state, including California's wildlands, farmland, cities, and landfills. It assesses California's ecological footprint on planet Earth. It discusses many different life forms found in soil, including bacteria, fungi, insects, and mammals. It features 92 color photographs and 18 maps A book in the Californians and Their Environment subseries, dedicated to understanding human influences on the state's ecology and natural resources.