TWO SUCCESSFUL PRESCRIBED BURNS IN THE ROCKY MOUNTAIN TRENCH SPRING 2021
The two prescribed burns planned for Premier Lake Provincial Park and Old Kimberley Airport (near Tata Creek) have been successfully completed from April to 15 to 17th 2021.
The Premier Lake Provincial Park burn was carried out in phases over April 15 and 16th by a BC Wildfire Management Service crew from the Invermere Fire Zone with funding and supervision by BC Parks. The completed burn area is approximately 131 hectares in size and is hatched red on the attached map. Because the burn is long and narrow it was not possible to build a good convection column to control the smoke and flames, so it was ignited by hand in small sections over two days. A second prescribed burn, 256 hectares and much wider in size is tentatively scheduled for fall 2021, as hatched in blue below.
The second burn at the old Kimberley Airport south of Tata Creek and Miller Road was a much larger square block of 320 hectares, as noted in red outline in the map below. A prescribed burn that was conducted in fall 2020 is outlined in green on the same map. This proximity of two burns will allow the Rocky Mountain Trench Ecosystem Restoration program to compare the effects of burning in fall versus spring on similar forests and terrain.
The operations on burn day were smooth and used a Wildfire Management Services Crew from Cranbrook Fire Zone with oversight from the Rocky Mountain Trench Natural Resources Society and managers from the Ministry of Forests Lands and Natural Resource Operation. Light up was at 12 noon Saturday April 17th and ignition was over by 2:00pm.
As this fire was much larger than Premier Ridge a helicopter and an Aerial ignition Device was needed to spread fire in the centre of the fire, create a convection wind to disperse the smoke and complete ignition in less than 2 hours.
To ensure the fire stays within the fire boundary the edges of the fire a lit by hand crews in tandem with the helicopter. Mopup crews follow the light up crews and ensure the flames do not jump the guard. Good grass growth in the summer of 2020 greatly aided the ease and success of ignition.
Smoke from the fire edge is pulled into the fire centre by the more concentrated, hotter fire created by the helicopter ignitions.
Although the smoke seems dense from the ground, it actually lifted up above ground level and slowly dispersed down the Trench towards Fort Steele in the south.
The Rocky Mountain Trench ER program did a quick review of the fire on Tuesday April 20th. The snow and rain experienced on Sunday the 18th put most of the smokey hotspots out. The guard was intact with no active escapes and about 80 to 90% of the ground area inside the burn had been blackened with a light burn impact with no areas of exposed mineral soils. All these observations to be confirmed by a full survey conducted six weeks after the burn. This allows for green up of vegetation so the burn impact on grass, soil and shrubs can be tabulated.
The main intent of this prescribed burn is to kill all regenerating Douglas fir and Lodgepole pine trees under one metre tall on the ridge top and midslope sections of the block. These are the units that produce the best grass and shrub growth on the block. The burn should also top kill the shrubs and allow the shrubs to regenerate from the base of the main stems.
Conversely the two prescribed burns in this unit create a large opening of about 787 hectares. The gulley bottoms and north aspects were not spaced, and the intent is to retain thickets and individual trees in the wetter sites to provide wildlife cover as an Open Forest unit. The trees in the draws are more likely to be Ponderosa Pine which are more fire resistant than Lodgepole pine or Douglas-fir. The grass in draws is also more likely to be low value pine grass and it has fewer high value shrubs. It appears that the Ponderosa pine survived this fire well; but this has to be tabulated by subsequent survey.
Special thanks to all our funders for this prescribed burn and for their support in the thinning and spacing projects over the past ten years; The Habitat Conservation Trust Fund, The Habitat Stewardship Program from Environment Canada and Climate Change, The Columbia Basin Trust, the Fish Wildlife Compensation Program (Columbia Basin) and funding from BC Parks, the BC Wildfire Service and the Ministry of Forest Lands and Natural Resource Operations.