How does soil color indicate organic matter content?

Soil color is a key visual characteristic that can provide insights into the organic matter content of the soil. Darker soils generally indicate a higher organic matter content due to the decomposition of organic materials, such as plant and animal residues, which contribute to the formation of humus—a dark, organic component of soil. The presence of this organic material affects the soil's overall color, making it appear darker, often rich brown or black.

For instance, soils that are rich in organic content, such as those found in forests or grasslands, typically display darker hues that signify a dense incorporation of decomposed organic matter. In contrast, lighter-colored soils, which may appear yellowish or gray, often contain lower levels of organic material, highlighting the importance of soil color as a visual indicator of organic content.