Forest fire

Figure 1: Forest fire in Canadian boreal forest[1]

Forest fires or wildland fires are spontaneously occurring forest, bush and plain fires and can occasionally be controlled. In Canada, uncontrolled wildland fires are most often associated with dry hot summers set off by lightning or human error. Forestry workers can also start controlled fires for a specific purpose such as removing pests and restoring ecosystems.[2][3]

Types of Forest Fires

There are three types of forest fires; ground fires, crown fires and surface fires.[2][3]

  • Ground fires occur below materials such as leaves and peat, these fires are slow moving but when left unattended, can take out large areas. These fires are particularly dangerous as they can ‘hibernate’ below the surface during a warm winter and re emerge once the weather gets warm again.
  • Crown fires pose the highest risk by far due to their fast spreading behavior, they develop on top of trees and in some cases can jump from one tree to another making these the most aggressive form of fire.
  • Surface fires are the most tame fire and can be put out relatively easily, these fires only occur at the surface and are generally no taller than the average human. Surface fires create the least amount of destruction.

Wildland Fire Causes

As previously stated, wildland fires are caused by two reasons, lighting and human activity. [3][4]

  • Lightning induced fires occur throughout the Canadian summer from the beginning of May though to the end of August. Before humans played a major role in forest fires, lighting induced fires were crucial to maintain a healthy natural ecosystem. They are triggered often when there have been long periods of drought and dry season and only produce under half the total forest fires every year. One major issues associated with lightning induced fires is the confusion factor, if more than one fire is triggered from lightning, it can be difficult to determine which fire should be dealt with first often resulting in the damage of human property and or life.
  • Human induced fires result in over half the total forest fires and are almost always mistakes. Whether an unfinished cigarette has been thrown from a car window or a bonfire is left over night, these fires are incredibly dangerous and can spread just as fast as naturally occurring fires. The biggest plus side to these fires is that they can be reported, located and dealt with relatively quickly.
  • Another type of human induced forest fire are prescribed fires which are essentially purposely set fires by professionals to manage other fires that may have grown out of control. These fires are also set to help restore weak ecosystems.[1]

Climate and Fires

Some argue that forest fires have a direct correlation to climate change. There is evidence that with rising temperatures, more fires have been occurring in the last couple decades in Canada. However, the Canadian climate has a lot of variability and this alters the patterns that one would associate with climate change. For example, in Northwest Canada, the amount of forest fires occurring has been rising in the last two decades; comparatively forest fires have been declining in southern Canada over the last two decades. Nonetheless, looking ahead, the number of annual fires is expected to rise in the 21st century, which will have a negative effect on the overall quality of living in Canada.[5]

Canadian Forest Fires

Canada, being a large country has many different weather systems and forests. The BC forests, especially the west coast forests, tend to stay wet as it is considered a rainforest. Although forest fires do occur, they occur much less frequently than in the boreal forests of Alberta and eastern BC. To view current and past fires Natural resources Canada has an interactive map of Canada that displays the fire dangers and active fires throughout the country.[6][7]

As of the summer of 2016, the forest fire around Fort McMurray Alberta was the most expensive natural disaster in Canadian history. Figure 2 shows how big the fire got.

Figure 2: The extent of the Fort McMurray wildfire in the summer of 2016. For more details please see the interactive map.[8] For a comparison of the size of the fire to various Canadian cities please see here.


  1. 1.0 1.1 NR.Can (2016, 07, 26). Forest Fires [Online]. Available:
  2. 2.0 2.1 Boreal Forest. Forest Fires – An Overview [Online]. Available:
  3. 3.0 3.1 3.2 NR.Can (2016, 01, 28). Fire Behavior [Online]. Available:
  4. NR.Can (2016, 01, 28). Fire Management [Online]. Available:
  5. NR.Can (2016, 02, 02). Climate Change and Fire [Online]. Available:
  6. NR.Can (2016, 07, 22). Fire Ecology [Online]. Available:
  7. NR.Can (2016, 08, 01). Canadian Wildland Fire Information System, Interactive Map [Online]. Available:
  8. NR.Can (2016, 08, 01). Canadian Wildland Fire Information System, Interactive Map [Online]. Available:, screenshot taken August 26th, 2016.

Authors and Editors

Lyndon G., Celeste Pomerantz, Jason Donev
Last updated: January 4, 2019
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