Most people don’t think about the soil under their feet, but basic dirt can reveal a lot about Earth’s past. Soil is formed from tiny grains of rock that existed many years ago. It can also form in the wake of landslides, volcanoes, and everyday weathering. This text takes readers underground to examine Earth’s many kinds of soil, the microorganisms and inorganic matter that make it up, and the critical role it plays in ecosystems around the world. Helpful diagrams, fact boxes, and sidebars support the information-rich text, which supports elementary science curricula, and colorful images will keep readers engaged from start to finish.