Effects of suppression of the natural fire regime

Temperate forests in the United States and Australia in which fire was deliberately suppressed are now experiencing devastating wildfires because of an unnatural accumulation of fuel. Deliberate human suppression of fire can also have direct negative impacts on species. In forests where fire is а natural part of the system, plant and animal species are adapted to а natural fire regime and benefit from the aftermath of а fire.

In North America,  fire suppression in   some areas  has contributed to

decline in the numbers of grizzly bear, Ursus arctos horribilis (Contreras and Evans, 1986). Fires promote and maintain many important berry-producing shrubs, which are an important food source for bears, as well as providing habitat for insects and in somecases carrion. The 1998 fires in Yellowstone National Park increased availability of somefood items for grizzly bears, especially carcasses of elk (Blanchard and Knight, 1990).

In boreal forests, exclusion of fire induces the build-up of organic layers that prevents melting of the upper soil during spring and summer and rise of the permafrost layer, resulting in impoverishment of forests, decrease in productivity and conversion of forests to marshes.

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Western Canada Wilderness Committee

Forest Fires

In the summer of 2003 British Columbia experienced a severe fire season. Tens of thousands of residents living in southern BC were displaced from their homes as forest fires ripped through wooded residential areas. The loss of homes and the destruction of thousands of hectares of forests caused many people to ask questions and search for answers. Why did this happen? Can we prevent fires of this magnitude in the future? Can we do anything differently?

The severe fire season in the summer of 2003 requires a careful analysis of the disparate factors that contributed to these events. We need a thorough understanding of the history and ecology of fire management and suppression in British Columbia before we can arrive at thoughtful conclusions that will help us to protect our public forests and the people who live near and in wooded areas.

It is often said that forestry is the engine that drives BC's economy. Although not as true in 2003 as it once was, it is not surprising that most British Columbians have some familiarity with the nature of the forests that surround our towns, villages and cities. Because BC's population is concentrated on or near the southern coast, the forests with which most people are most familiar are the majestic ancient temperate rainforest valleys. This summer, however people became aware of the equally vast stretches of "fire forest" in the province's southern interior.

Rainforests and the drier interior forests are both intricate forested ecosystems that support wildlife and a variety of plant and trees species that are specifically adapted to the different ecological conditions of these geographic areas. As the name implies, rain (and lots of it) is absolutely critical to the health and ecology of the rainforest. In the fire forest of BC's southern interior it is fire that provides one of the essential conditions for a healthy forest.

When humans think of fire, they tend to think of destruction and devastation which in part explains why the provincial government has historically pursued a policy of fire suppression in all the province's forests since the major forestry companies arrived after the Second World War. The theory, popularized in the United States by Smokey the Bear, was that fires were a threat to forest health and suppressing fires would leave trees standing for logging later.

By actively suppressing forest fires the government has unwittingly contributed to a scenario where underbrush, ingrowth of saplings and dense reforestation have created conditions where catastrophic fires become inevitable. By changing the fire regime in the southern interior's forests we have done exactly the opposite of what was intended.

Frequent, low severity restorative surface fires that contribute positively to forest health and leaves trees standing have been replaced by less frequent, catastrophic fires that burn through the crowns of trees, incinerate soil and threaten human life and property.

Another effect of suppression in BC's southern  interior fire  forests has

been greatly reduced resistance to massive insect infestation such as we've seen with the mountain pine beetle.

The normal fire regime must be returned to the southern interior forests if we are to minimize the risk of another season of catastrophic fires such as we have seen in 2003. Restoring ecological balance will ultimately result in naturally diverse forests that are more resistant to fire, insects and disease, as well as forests that provide far better wildlife habitat. Human interfaces, areas where development such as houses intersect with forests, need to be carefully considered in building codes to reduce future risk to human life and property.

Below you will find more information on this year's forest fires, fire ecology and what can be done to help BC's southern interior forests return to a state closer to their natural ecology.