Pitch Basics

• Pitch is a highly flammable hydrocarbon secreted by softwood conifers, including cedar, fir, hemlock, pines and other trees that bear needle-like leaves. Firewood from Douglas fir contains an especially large amount of pitch. Pitch burning in firewood from conifers is the main reason why they produce hot, fast fires. Hickory, oak and ash and other hardwoods that do not contain pitch burn more slowly, which is why they are generally preferred for firewood.
  
  

Creosote

• Fire is composed of gas and particles of soot, which is unburned carbon. Soot in smoke below 250 degrees Fahrenheit turns into brownish-black, liquid creosote that runs down the insides of chimneys and can slide onto the sides of your fireplace. Foul-smelling liquid creosote turns gummy and eventually hardens. Creosote is flammable and can cause serious fires if you let it collect in your chimney or the sides of your fireplace. Pitch does not cause creosote --- smoke does.
  
  

Pitch and Creosote

• Cool smoke causes creosote. Wet wood smokes. If you burn wet softwood that contains pitch, the pitch allows it to burn, but the moisture creates the cool, creosote-producing smoke. If you burn dry softwood that contains pitch you will get a hot fire that produces little smoke, so it does not produce creosote. Since pitch-bearing softwood will burn even if it is not properly cured, some people burn it anyway, incorrectly blaming the smoke on the pitch. If you burn wet hardwood, it will smoke, too. To avoid the dangerous accumulation of creosote, burn dry firewood that does not smoke.
  
  

Lightwood and Fatwood

• Native Americans and pioneers valued flammable pitch as a means of starting fires. They carried pitch with them to help them start fires, and they used kindling containing pitch to start fires, calling it "lightwood." More recently, enterprising entrepreneurs have been marketing kindling containing pitch as "fatwood," an environmentally friendly alternative to chemical fire-starting liquids. The "fat" in fatwood refers to its pitch content.