Picture of the week



Archaeology in the Fort McMurray Fire

View from a burned aspen stand to the Gregoire River valley.

At the end of June we started work on planned fire salvage harvest blocks for Alberta-Pacific Forest Industries, southeast of Anzac Alberta. This was the southeastern end of this springs massive Fort McMurray forest fire. When fire kills or damages a stand, there’s a limited time-frame within which the wood can still be salvaged for lumber or pulp. Planning for salvage started before the fire was under control. Once it was safe to do layout work we had a narrow window to get in and complete our Historic Resource Impact Assessment of the salvage plan before harvest operations would start.
As the Forest Management Agreement holder for most of northeastern Alberta, Alberta-Pacific Forest Industries has a long-term right to harvest aspen and poplar for their pulp mill north of Athabasca. This long term land tenure comes with a lot of responsibilities. These include a responsibility to salvage as much timber as they can from wildfires, and a responsibility to complete historic resource impact assessments of their operations.
The Historic Resource Management Branch of Alberta Culture understands that fire salvage is not part of a forest company’s normal Annual Operating Plan. It’s often difficult to know the final block boundaries until harvest is complete because the timber has to be damaged by the fire, but not too burned. There is therefore some concession given for late-season or last-minute salvage plans, which can be deferred to post-harvest impact assessment the following season.
In this case, Al-Pac wanted to ensure due diligence by completing their HRIA’s prior to salvage, so we started our fieldwork immediately after the layout crews finished putting up their block boundary ribbon. Fire salvage can be both a challenge and an opportunity for historic resource management. In addition to the logistical challenges of the narrow timeframe and uncertainty, working in a fire stand increases some safety hazards. There is of course the risk of holdover fires or flareups. There’s also an increased risk of blowdown from snags (standing dead trees) with their roots burned out and hangers (fallen trees and limbs hung up on other trees). Foresters call these “widowmakers” for a reason. There is often increased bear activity as they take advantage of the fresh green growth, grubs, and in later summer berry production, made available by the fire.
Forest fires also increase the risk of impact to archaeological sites. Forest harvest operations are normally pretty low impact, as far as archaeology is concerned. Feller-bunchers and skidders have large tracks and wheels to keep their footprints light. Under normal conditions, harvest leaves some tracks and trails, but the thick moss and duff of the boreal forest protect buried archaeological sites from a lot of the potential disturbance. A hot ground fire burns off much of the moss and duff, leaving the shallowly buried artifacts typical of the boreal forest much more vulnerable to exposure and displacement.
This factor is also what makes some fires an opportunity for archaeology. One of the hardest parts of doing archaeology in the boreal forest is the fact that everything is covered by a mat of moss, with almost no surface exposure. The only way to find sites is to dig labour-intensive shovel tests, and these provide very limited windows into the buried past. In a hot fire, the moss has been burned off, and we can see a much larger window. In some cases, scatters of artifacts, in-situ (in place) where they were left thousands of years ago, are sitting on the surface.
That wasn’t the case this week. We found a couple of sites where the fire didn’t burn quite that hot, including a probable Besant point, but we had to dig for them, as usual.
I also found a renewed appreciation for the resiliency of the boreal forest, and how well it’s adapted to a frequent fire regime. It’s only been two months since the fires burned through the area, and most of the burn is covered in a lush green carpet of fresh growth. Plants like fireweed, sasparilla, wild rose, raspberry and bunchberry have sprouted from root systems protected from the fire. Aspen and poplar suckers with huge deep green leaves are already knee to hip high. Insects are present in abundance, birdsong can be heard, deer and moose sign shows they’ve returned, and we saw a black bear sow with two cubs.

By salvaging the burnt timber, Al-Pac will help to fast-track that cycle of renewal, and will leave other areas they’d planned to harvest to grow for another season or two. By having us complete our historic resource impact assessments before harvest, we’ve identified and protected two potentially significant archaeological sites in an area that’s still pretty poorly understood. These are some good examples of how the forest industry plays an important role in Alberta’s woodlands, helping to manage multiple values on the landscape, and balance their operations with ecological and cultural concerns.