How do I cook on a fire?
To answer this question, let’s run through a list of common items that one may find on a typical camping trip:
Tent: A tent would probably burn a little bit, but then you would have nowhere to sleep.
Water: Also a poor choice. If water is flammable, don’t drink it.
Car: Although action movies lead us to believe that cars are incredibly flammable, it is not advisable to use your car as fuel. Burning cars make a lot of smoke, and you would have no way of getting home.
Marshmallows: Marshmallows are super flammable. When lit, they expand and bubble and morph into a gooey blob. Fun to watch, but not a good way to sustain a fire.
Someone else’s tent: Plausible. Best candidate so far.
Sleeping bag: A good sleeping bag will be filled with goose down, often treated with chemicals to be resistant to water. While I am not familiar with the manufacturing processes, it can be assumed that burning a sleeping bag would release some harmful toxins into the environment. Not as bad as a car, or toxic water, but still inadvisable. Also, you would have nowhere to sleep.
Clothing: Slightly flammable, but needed to help keep bugs away.
Alcohol: Flammable, but who in their right mind would burn their alcohol??
Sticks: Sticks can be found all over the forest and are an excellent source of fuel. Of all of things on our list so far, wooden sticks are definitely at the top of the list. As Winston Churchill once said: “Sticks are great for making fire”*. But there are so many types of sticks. Which ones are the best for keeping a fire alive?
The best items to start a fire are actually not sticks themselves. Sticks take a threshold of heat to ignite and burn, and a lighter or a match will rarely be enough to meet that threshold. To get a fire going, try Birch bark, which contains natural oils that will burn hot enough to ignite your sticks.
A stick’s ability to ignite depends a great deal on its thickness. The science is more complicated than this, but the bigger the piece of wood, the more heat is needed to ignite it. For this reason, the best way to start a fire is to start with something that can generate a lot of heat for an extended period of time (like Birch bark) and then use this heat source to ignite very small sticks – only a few millimetres in diameter.
Once these small sticks ignite, you can move on to larger sticks – up to a centimeter in diameter – and then onto larger and larger pieces. As the fire grows, more wood can safely be put in, and more heat is generated, creating a chain reaction that eventually allows us to add large firewood.
Flames rise upwards, so putting your ignition source (in this case, Birch bark) at the bottom makes the most sense. On top of this should go the smallest sticks, and then once the fire catches, larger and larger sticks can be added on top. There are some great fire-building set ups that take these concepts to the next level, but we’ll look at this in another blog.
Fire also needs oxygen to burn, so keeping airflow is critical to starting and maintaining a fire. If too much wood is added to a fire, it can cut off oxygen and smother the flames. This is a common problem when starting a fire. If this happens, the fire risks going out, leaving you with a heap of smoking hot sticks. If this happens, try blowing on the base of the fire. Your breath can actually revive a dying fire.
As you may have guessed, dry sticks burn better than wet sticks. Since living trees are full of sap, they are very wet, and will not burn well. This is why it doesn’t make sense to cut down trees or break branches to fuel a fire. Wet or living wood will create a lot of smoke, and will often smother a fire. Similarly, rotting wood will have the same effect. Use sticks that break easily when bent – this is a good sign that they are dry on the inside.
There are many different types of wood, and each of these burns slightly differently. I won’t go into the details of each type, but as a rule of thumb, harder wood like oak burns slower than softer wood like pine.
Flashlight: Not flammable, and batteries are toxic when burnt.
Rocks: No, these don’t burn very well.