Did you know that Wildfires are all NSA (Nature’s School of Alchemy) graduates? Not only can they use heat to transform matter and oxygen into ash and smoke, they can perform amazing transmutation tricks with dirt and soil!

Transmutation #1: Waterproofing dirt

You’d think after a raging wildfire, the ground would be parched and love a good drink of water, right? Wrong. In a twist worthy of a magic trick, a high-intensity fire can actually turn the soil completely waterproof!

Here’s how that happens: Plants are full of natural oils, resins, and waxes. When they burn, these compounds vaporize into a gas. This gas gets pushed down into the soil, away from the heat. As soon as it hits a cooler layer of dirt underground, it condenses and hardens, coating the soil particles in a waxy, water-repellent layer, creating so-called hydrophobic soil. Basically, the ground puts on a raincoat!

Transmutation #2: Slip ‘n Slide

Now, the underground dirt is bone dry and shielded. But the top layer? That gets nice and soggy with a good rain: Muddy top layer meets waxy bottom layer, and … boom, instant Slip ‘n Slide!

Transmutation #3: Shocking Nutrients

When wood and leaves burn, carbon floats away, but minerals like nitrogen, phosphorus, and potassium stick around. You might think this would be a miracle fertilizer, but it can actually be too much of a good thing. This “nutrient shock” can burn the roots of sensitive native seedlings. Even worse, because there are no plants left to drink up these nutrients, the first rain washes them straight into local streams, causing algal blooms that can choke out fish and contaminate water supplies miles downstream.

Transmutation #4: pH Flip Flop

Have you ever heard of “potash”? It’s an old word for potassium salts, historically made by soaking wood ash in water. Ash is highly alkaline (basic), but forest soils — especially under pines — are usually acidic. One wildfire, and suddenly the soil is a weed-friendly party zone, while native plants get locked out. Nature’s chemistry upended!

What can you do?

BEFORE the fire: Clear defensible space around your home, and use  fire-resistant materials and plants in your landscaping, to keep fire from playing in your dirt.

DURING the fire: Beware of walking or driving on dirt in a burned-out area, especially if there’s water from rain or firefighting efforts around that may create sneaky Slip ‘n Slides.

AFTER the fire: Loosen the top 2–6 inches of soil in any burnt areas around your home or garden, breaking up the waxy, water-repellent layer. Consider having garden soil tested for pH levels and alkalinity, and use soil amendments if needed.

RIGHT NOW: Make a donation to help Creative Crisis Leadership turn complex science into simple, life-saving knowledge!

Sources

1. How Does Wildfire Affect Soil and Vegetation? | Western Fire Chiefs Association
2. How Does Wildfire Impact Soil Health? | Fire Safe Sonoma
3. Vahedifard, Farshid, Masood Abdollahi, Ben A. Leshchinsky, Timothy D. Stark, Mojtaba Sadegh, and Amir AghaKouchak. “Interdependencies between wildfire‐induced alterations in soil properties, near‐surface processes, and geohazards.” Earth and Space Science 11, no. 2 (2024): e2023EA003498.

 

Stay Safe and Be Curious this Holiday Season!