101 Questions answered
Fire and Water Repellent Soil: Why Burning Isn’t an Effective Management Tool
Yes and no. The temperature of the fire affects the impact on water repellence in the soil.
During a bushfire, if temperatures exceed 300°C, the organic matter at the surface vaporises and moves deeper into the soil. As it cools it condenses again, forming a water repellent layer at around 5–10 cm depth.
Burning stubbles tends to be a cooler fire which consumes or ‘burns off’ organic matter. This can reduce water repellence, but comes with the greater cost of losing soil organic matter. Burning can also make infiltration worse by burning-off old crowns which help water find the pathway into old root channels.
Burning stubble is not a good way to manage water repellence.
