O Horizon

The O horizon is the uppermost layer of soil, primarily composed of organic material such as decomposed leaves, plants, and other biological matter. It is rich in nutrients and plays a crucial role in supporting plant growth. This layer is typically dark and can be quite thick in forests or areas with lots of plant material. The O horizon helps retain moisture, improves soil structure, and provides essential nutrients to the layers below. Its presence and thickness can vary depending on the environment and type of vegetation present.