Cottage Q&A
QUESTIONWe're planning on making a fire pit at our cottage but aren't sure where to put it. I'm worried about causing a root fire, which I've heard can spread underground. How do I make sure our pit is in the right spot?
ANSWER
You're right to worry. In fact, a little paranoia when it comes to root fires is a good thing. Here's why: Even though a campfire appears to be extinguished, it could have ignited roots and other combustible material below ground. Fed on abundant fuel where there is also plenty of oxygen, a root fire travels underground, eventually surfacing elsewhere as an above-ground fire. A fire usually burns in the duff layer, or first few centimetres, explains Stephen Hernen, fire chief at the Huntsville/Lake of Bays Fire Department. But in a dry summer, it can easily migrate down as deep as 45 cm, following squirrel and chipmunk holes. Once that root fire is born, it can burn - for months. Seriously. "I have heard of cases where fires smouldered underground for six to eight months," Hernen says.
Root fires are tricky because they can pop up several metres from the original burn. They are also silent killers. Bud Andress, public safety specialist and senior warden at St. Lawrence Islands National Park, instructed some campers to put out a fire on a rocky point that was surrounded by 100-year-old white pines. The campers complied, but three years later, the trees were standing dead. The fire had travelled underground and burned the roots, which eventually killed the trees.
Have we scared the bejesus out of you? Don't worry, there is a way to enjoy a fire pit at your cottage without worrying you could murder a prized pine. First, clear away combustible material and dig down at least 30 cm. If you encounter tree roots, find another spot because hacking back roots can damage a tree. Now, fill the hole with gravel or sand - preferably sand because it is more compact. Don't forget to ring the pit with stones and, voilà, you have a fire pit that even Smokey the Bear would approve.
* Published in the March 2006 issue of Cottage Life
