What is the characteristic color of soil with excessive internal drainage?

Soil with excessive internal drainage tends to exhibit a characteristic rust or really brown color due to the oxidation of iron compounds present in the soil. When soil drains well, oxygen can easily penetrate, promoting the oxidation of iron, which imparts a reddish-brown hue to the soil. This reflects the well-aerated conditions that prevent excessive moisture retention, leading to the formation of these vibrant colors.

In contrast, soils that have poor drainage might display grayish hues or mottled patterns due to saturation and the reduction of iron, which occurs when soils remain waterlogged. A uniform brown color might indicate some level of moisture retention but doesn’t exhibit the distinct rust coloration associated with good drainage. Thus, the presence of a vibrant rust or really brown color serves as an important indicator of excessive internal drainage in soil profiles.