View from Castle Junction of prescribed burning on the Sawback Range in 1992 and 2016. Both burns had their environmental benefits and costs. The spring 1992 burn was large and moderately intense, removing a broad swath of mature forest, but south-facing grasslands began sprouting back immediately. Soils were moist and the fire completely self-extinguished within 20 hours. Due reduced fuels from previous prescribed fire, the fall 2016 burn was lower intensity but did remove a large amount of forage on the Sawback Range’s bighorn sheep winter range. Neither burn reached into habitats needed regenerating in valley’s bottomlands. Indigenous fires were likely often in the spring season and partially focussed on valley-bottom areas. The 2016 fire was the last large-area prescribed fire in the Bow Valley, and the only large fire in the valley in the last 2 decades. The aging forests in the foreground are highly susceptible to massive mountain pine beetle mortality.
For over four decades Banff National Park’s fire management program has been one of the most advanced in the northern hemisphere. Recently the program in the Bow Valley have faltered as political realities increasingly constrain prescribed fire use. However, the other options—large timber harvesting cutblocks or massive wildfires—are also controversial management directions for Canada’s first national park. Castle Junction, where the Kootenay Parkway coming over from British Columbia joins the Trans Canada Highway is a good place to contemplate three kinds of fire so well described by Stephen Pyne in his recent book “The Pyrocene”:
- Lightning fire or nature’s burns that for millions of years balanced the biomass created by photosynthesis. These fires can still frequently spill into the Bow Valley from the lightning-prone forests to the west.
- Indigenous fire that since the ice from the last great glaciation retreated have dominated landscapes heavily used by humans. The Bow Valley was one of these places—with abundant bison and bighorn sheep, and a rich herbaceous and shrubby bottomland it was an ideal location for humans if routinely burned to maintain habitats.
- Lithic fire that increasingly dominates global combustion as humans exploit the energy of the ancient carbon buried in rock and return it to the atmosphere. This industrial fire brought the railroad to Banff in the 1800s, the Trans Canada Highway in the 1900s, and the millions of visitors now streaming through the each year. Today, lithic fire destabilizes the long-term role long-term roles of lightning and Indigenous fire in balancing the earth’s carbon cycle.
This section describes Banff’s past progress, current problems and some prospective pathways for future fire management as the intermixing of these three sources of combustion create increasingly complex dilemmas.
