Calcined Bone

When bone is burnt by a fire it can undergo a range of changes in appearances, such as calcining. Calcining, characterized by its bright white colour, is caused when bone is burnt at a higher temperatures. The bone can shrink, become more white or chalky in appearance, more fragile and more likely to fragment into smaller pieces. These pieces of calcined bone were collected during the summer of 2017. Calcined bone indicates the presence of a hearth at the site.

Abandoned Campfire

Living in Alberta, we all know how disastrous a forest fire can be. Some of you might have been personally affected by the devastating fires in Fort McMurry or in Slave Lake. Brian knows personally how dangerous forest fires are because he used to be a forest firefighter. Many of us at Tree Time have walked though the remains of a burned forest and have seen what is left behind.

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Figure 1. An area that was partially burned by a forest fire

So when Brian and I were working the in foothills around Rocky Mountain house and we saw the remains of a smouldering fire, we took it seriously.

We noticed the smoke in the morning as we walked to our first target. The campfire had been abandoned, likely by people camping during the May Long weekend. This means it was likely burning unattended for three days. It looked like people had been burning garbage in the fire pit, including a mattress. The mattress frame was smoking heavily. The ground around the campfire was also smouldering a bit, and somewhat hot. The area around the pit was clearly burnt.

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Figure 2. Note the burnt ground under Brian’s feet clearly outside the intended fire pit area

We put out the frame with water from a nearby creek. It was so hot that it caught fire again as soon as the wind touched it. Back at the campfire, we used our shovels to dig up the earth around the firepit and in the pit itself. Brian told me that he had fought many fires during the May Long weekend that started in this exact way. Not because of people burning garbage, but because of abandoned fires. People might think that they put out their fire, but debris (roots, moss etc) on or under the ground can catch on fire and spread the fire beyond the stone rings. You can see in the pictures that the area around the campfire has been burned.

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Figure 3. Brian digging up earth around the fire pit to put out the fire

That is why it is so important to make sure that you have properly put out your fire. Please check out the Alberta Parks Website for great advice on campfire safety.

http://www.albertaparks.ca/albertaparksca/advisories-public-safety/outdoor-safety/campfire-safety/

http://www.ofc.alberta.ca/camping-and-outdoor-fire-safety

Also if you need to report a wildfire, call 310-Fire (3473). Never put yourself in danger.

We thought we would share this story in advance of the long weekend to remind people about campfire safety. Alberta is a great place and camping is an amazing way to experience it. So from us at Tree Time, we sincerely wish you a great long weekend and happy, safe camping.

Fire Drill

Our clients require us to carry fire fighting equipment including shovels, pulaskis, fire extinguishers and full backpack fire pumps, also commonly known as ‘piss packs’. At the end of a shift we decided to do a quick drill to make sure everyone knew how to use the fire pumps, which had the extra bonus of giving us a head start on washing the trucks.

The Archaeology of Wildfire

This is a guest post by Christina Poletto, a Master’s student with the Institute of Prairie Archaeology at the University of Alberta Department of Anthropology. She’s studying the palaeoenvironmental signature of wildfire, to look for signs of pre-historic controlled burning by indigenous societies in northeastern Alberta.

Fire is almost a constant in Alberta’s north, and its impact can be felt not only on the environment but on populations. In recent years’ fire has been seen in a negative light due to extreme fires that have impacted communities in northern Alberta. The 2016 fire in Fort McMurray has had a devastating impact on people in the area, displacing thousands and damaging houses and buildings. However, fires were not always this large and destructive.

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Wildfires from 1930 to 2014. This map only presents 84 years of fires in the area, but it shows the frequency and scale of fires in the region. (Fire history from Canadian Forest Service. 2011. National Fire Database – Agency FireData. Natural Resources Canada, Canadian Forest Service, Northern Forestry Centre, Edmonton, Alberta. http://cwfis.cfs.nrcan.gc.ca/en_CA/nfdb.; map created by C. Poletto)

As part of the boreal forest’s natural cycles, fires allowed for a diverse mosaic of landscapes to be re-established and helped support animal communities in the area. These natural fire cycles also help to remove ‘dead’ organic materials like fallen trees and overgrown plants. If these materials are left to build up, they become another fuel source for fire and make fires more intense. This has led fire scientists to argue that the more the forest is regulated and the more fires are suppressed, the more intense and dangerous fires become. In the years before fire suppression, fires were a crucial and positive part of the success and diversity of the boreal forest.

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Dense forest cover can be both fun and challenging when accessing sites. For fires though, this can mean a faster moving and more intense burn (image C. Poletto)

In addition to natural fires, northern Alberta First Nations groups had traditions of cultural burning. These fires were highly regulated; they were only started under specific circumstances and were dependent on factors like weather conditions and the amount of fire fuel in an area. Early spring was the preferred season because the ground was dry enough to burn but damp enough to prevent the fire from getting too large, whereas during the fall it was drier, making it more dangerous to begin burning. When all the conditions were right, fires would be used to create landscape features like hay meadows or to form and maintain trails, and to promote plant and animal communities re-entering into an area. Ethnographic studies like ones conducted by Henry T. Lewis and Theresa Ferguson with the Dene-Tha (Slavey) in northwestern Alberta documented the longstanding tradition of controlled burning. Elders commented that these practices would not only promote the movement of people but would encourage vegetative communities to thrive and entice animals to revisit areas. In the forest, ensuring the availability of food resources for the months ahead and for years to come was the primary goal of these activities, which is why such great care was taken with the burning process.

In an archaeological site with deep deposits, records of these traditions could be noted by multiple layers of charcoal related to occupation periods. However, in many parts of the boreal forest, the soil deposits are shallow and make it challenging to see these patterns. Instead, researchers can look at soils in lake basins to help recreate these parts of the record. With these ancient and modern records, we can understand how different plant species respond to different fire types, and model the regrowth and response of animal communities. Understanding how First Nations groups manipulated these environmental relationships enhances our understanding of past groups living in the boreal forest. IN addition to its archaeological value, this knowledge can be integrated into modern forest management practices. In some parts of Alberta, highly regimented cultural burning through collaborative efforts has been reintroduced as a way to help minimize fire risk and to promote a healthy, diverse boreal forest.

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This map of the Clear Lake – Eaglesnest Lake area in the Birch Mountains shows how we can use current vegetation data to see how the boreal forest responds to fire. It also serves as a baseline for future research to attempt to interpret the boreal forest’s story of fire from lake records (created by C. Poletto).