What Makes Soil Hydrophobic

Hydrophobic soil is most familiarly formed when a fire or hot air disperses waxy compounds found in the uppermost litter layer consisting of organic matter. After the compounds disperse, they mainly coat sandy soil particles near the surface in the upper layers of soil, making the soil hydrophobic.

Can soil hydrophobic?

Many potting soils become hydrophobic—tending to repel water—when they dry out, and are difficult to re-wet. … But the water might be running between the side of the pot and the hydrophobic root ball instead, barely wetting the outer surface and leaving the center of the root ball dead dry.

How does fire make soil hydrophobic?

The hydrophobic layer is the result of a waxy substance that is derived from plant material burned during a hot fire. The waxy substance penetrates into the soil as a gas and solidifies after it cools, forming a waxy coating around soil particles. … During an intense fire, these substances move into the mineral soil.