Private forest land managers – like many in BC right now – are trained on the drought conditions that have spurred a very aggressive wildfire season in some parts of the province. One of the predictors of wildfire behaviour is the condition of the fuels. But what are fuels? Anything that can burn, including grasses, shrubs, trees, dead leaves, and fallen needles, is fuel for a wildfire. Excess fuel can cause fires to burn hotter, larger, longer and faster, making them more difficult to manage.
Why manage fuels?
- We manage fuels to maintain ecosystems. Wildfires can be devastating, but not all fire is bad. Fire plays a necessary role in many landscapes. Periodic low-intensity fires speed up the process of forest decomposition, create open patches for new plants to grow, improve habitat and food for animals and deliver nutrients to the plants that survive. Some research indicates fire may also improve ground water recharge and water flow to aquatic habitats. Some trees, like lodgepole pine, require the heat of flames to open up their cones and disperse new seeds.
- We manage fuels to reduce the chances that lives or property will be lost to wildfire. Houses near grasslands, forests, or other undeveloped areas (known as the wildland urban interface) are vulnerable to wildfires because they’re essentially surrounded by fuel. The extent and density of vegetation around a structure influence the ability of firefighters to prevent it from burning in a wildfire. Fuel treatments make unwanted wildfires less likely and easier to manage.
- We manage fuels to improve the efficiency and safety of wildfire suppression. The amount of fuel has a decided effect on fire behaviour. Very low volumes of fuel can result in a low intensity, creeping fire. On the other hand, large volumes of fuel could result in a blow-up fire that is difficult to control.
Fuel’s Effect on Fire Behaviour
The elements of wildland fuels include fuel loading, size, arrangement and moisture content. The amount of fuel has a decided effect on fire behaviour. Very low volumes of fuel can result in a low intensity, creeping fire. On the other hand, large volumes of fuel could result in a blow-up fire that is difficult to control. The more fuel burning, the more heat produced.
How do we manage fuels?
Managing fuels means reducing their availability to feed a wildfire. We can do this by :
- Deliberately starting a fire under favourable conditions (so we can manage where and how the fire burns) in order to remove excess vegetation
- Thinning forested areas with equipment or by hand
- Reducing the quantity of grasses and shrubs mechanically or by placing domestic, grazing animals (e.g. cows, goats) on a landscape.
- Treating an area overgrown with invasive plants
Fuel treatment projects occur year-round depending upon location, vegetation type, weather, and many other factors.
For more information on fuel management, visit the BC Government’s ‘Tools For Fuel Management’: https://www2.gov.bc.ca/gov/content/safety/wildfire-status/prevention/vegetation-and-fuel-management/fire-fuel-management/fuel-management