I came across this note last week when I was hiking south past Rainbow Lake on the Maine Appalachian Trail. It reads:
HELP, Aug 7 11AM, All Hikers, Towards the lake, I found a root fire. I’ve spent the past 2.5 hours digging up the ground and dumping H2O. Please take a minute of your hike to check up on the area (towards the shore, against the large mosey rock.) Forest Service is on their way. Still, please check on it even if it is raining. Thanks Cj, Abol RR MATC BSP (Ridgerunner, Maine Appalachian Trail Club, Baxter State Park).
What is a root fire?
A root fire is a fire that burns underground along the root system of a tree. It’s a very dangerous form of fire because the fire can smoulder for months underground, long after the surface part of the fire has been extinguished. Root fires can also travel underground and resurface some distance from their point of origin.
The threat of root fires is especially serious in forest habitats with extensive root systems, like Maine’s 100 mile wilderness. Root fires can be started by lightning strikes, campfires, or even an errant cigarette butt, and major forest fires have been attributed to them.
Leave No Trace Campfires
If you ever hike or camp in Maine, it’s important to understand the dangers of starting any kind of fire and the potential for root fires. Given the risks, you might consider foregoing a fire or at least teaching your group how to build a leave no trace mound fire with a fire resistant cloth and a mineral soil.
To build one of these, you lay a fire-resistant cloth on the ground and then pile mineral sand, like beach or stream bed sand on top it. Once the mound is created, you build a fire on top of it, instead of bare ground. The mound creates an insulation barrier that prevents the ground under the fire from being scorched and preserves the micro-organisms or plants living there. The mound also prevents root fires because it stops the propagation of the fire below the fire-resistant cloth.
Fires can be fun, but you need to understand all the consequences of building them and learn how to do it responsibly so that others can enjoy the woods after you’ve gone. Burning down the forest in order to roast some marshmallows is not a good tradeoff. If you want to build a fire, learn how to do it responsibly and leave no trace.