Burning Down the House

. . . and the forest, and the grassland, and the scrub.

I’ve been following the Canadian news about the Alberta forest fires, in part because fire history is a small part of my non-fiction research. As best we can tell, humans discovered very early in our development that fire was a useful tool. And I suspect that a very few days/hours later, Ogg swatted one of the Oggetts for lighting the grassland on fire and forcing the band/tribe to flee. Fire is a critical tool in humans’ bag of tricks, and has been part of the larger environment since the Earth’s atmosphere first had enough oxygen to permit burning.

Fire is an excellent tool for managing certain environments, like many kinds of forest and grasslands. It removes dead material, releasing the nutrients back into the soil and atmosphere so it can be recycled. Low creeping “cool” fires prevent the build up of a large fuel load, so you are far less likely to get enormous end-of-the-world “Run Bambi!” fires. What you see below is a pretty good animation of a potential crown fire.

Some plants, and entire ecosystems, are fire-dependent, or “pyrophillic” (fire-loving). Fire weed, some conifers, some Australian ecosystems, and the upland scrub ecosystems of southern coastal California are examples. The tall-grass prairies of North America became fire-favoring over the course of ten thousand years of management by humans. They are one of the best known, but the southeastern woodlands also were burned, in order to thin out the underbrush and encourage the growth of young plants, the kind deer liked. I’m not familiar with any literature about the steppes of Eurasia being fire managed the way North America was, but that may simply be because trying to find archaeological traces of deliberate burning can be well-nigh impossible after so long. The kind of fire that would leave a marked soil horizon would be a very unusually intense event.

The problem with fire is when humans get up close and personal with it. Or I should say, up close with lots of personal belongings. Any house fire is a sad thing for the people involved, and all too often a tragic thing if people (or their pets) die. I will admit a bit of Schadenfreude for those who build into the woods, have wooden roofs on their houses, refuse to clear the trees and underbrush around the structure, and then get caught. (I’m not talking about the folks in Australia a few years ago, where the government forbade them from taking precautions. That’s different.) But when you get a serious fire year, as has happened down in the Texas Panhandle and farther south in Texas in the past decade (Bastrop Fire 2015, TransPecos 2015, Panhandle 2006, Fritch 2015), or the big burns over in New Mexico, anyone near the forest is at risk.

Forest fires, once they reach a certain size and intensity, create their own weather, exacerbating and spreading the flames by scattering debris and generating wind that feeds the flames. Think about hot air, how it rises. Something is going to fill that void, and so air from around the rising column flows in, adding fresh O2 to the combustion.

Hmmm, this looks like a thunderstorm with a tornado, doesn't it? http://6336-presscdn-26-82.pagely.netdna-cdn.com/wp-content/uploads/2013/10/pyrocumulus.jpg

Hmmm, this looks like a thunderstorm with a tornado, doesn’t it? http://6336-presscdn-26-82.pagely.netdna-cdn.com/wp-content/uploads/2013/10/pyrocumulus.jpg

So what happens when you get the perfectly (bad) combination of  a wet year followed by drought and a no-burn or limited-burn management policy, and high pressure dominating the regional weather?  Alberta 2016.

Or Peshtigo Wisconsin 1871, which may be the worst single loss of life from a forest fire in US history (thus far). The Peshtigo fire took place at the same time as the Great Chicago Fire, but consumed more acreage and took more lives. I’ve seen some photos of the aftermath. The charred bodies, even in black and white, were too much for me. http://www.peshtigofire.info/  is a good single-point resource for information on that event. The illustration of the fire-nado destroying the church is quite something.

So what’s going on in Alberta? A perfectly bad combination of location, weather, people living at the edge of the forests, and an area that is hard to reach with fire-fighting equipment. Plus the tar-sands are a major source of Canadian income, and even those not directly in the path of the flames or involved in trying to fight and manage the fire-fighting efforts are going to be affected by the smoke and the flood of refugees.

http://www.wri.org/blog/2016/05/5-images-explain-why-alberta-forest-fires-are-so-hard-stop 

The above is an excellent article about the events in Canada and why the fires are such a major problem. The image below is from two years ago, another not-great year for northern Canada.

What will the results of the fires in Alberta be? In the short-term, a disaster for the province and especially for the people who have lost everything. A small city of 80,000 is gone for the most part, along with smaller communities. One rains do come, erosion and water pollution are going to be concerns because all that ash is going to run downstream, and some slopes will slip (as happens in California every year or so). The forests will look horrible, and in some places I suspect the soil has been sterilized and maybe even turned to a hard glassy layer by the heat of the flames. But in time, a decade or so, shorter where things were cooler, the forest will return. Grasses and forbs will come first, along with insects, then brush, then trees. Until then, well, it will be black and depressing and dangerous until all the “widowmakers,” the part-fallen trees and snagged limbs, fall down.

A fire in Montana, photo by John McColgan. From: http://www.cbc.ca/archives/content/images/forestfires_homehr2_en.jpg

A fire in Montana, photo by John McColgan. From: http://www.cbc.ca/archives/content/images/forestfires_homehr2_en.jpg

There are areas near my day job that really need a good controlled burn to freshen the grasses up and to knock down brush and weeds. Emphasis being on controlled. It will not happen because of development in the area – people tend to get nervous when you show up behind their back fence with a kerosene torch, a plan, and assurances of “no worries, the wind’s out of the north, you’ll be fine.” Fire is one of our greatest assets and best tools. But when it gets away from us, or when things get hot along the urban-wildland interface, woe betide the mere mortals standing in the fire’s way.

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2 thoughts on “Burning Down the House

  1. I always take a double take when people start talking about April and May as fire season. Here the snow has just gone (it is still usually around, at least in drifts, if not falling fresh in April), in fact I got snowed on last week while working, admittedly I was around 6000 ft. but it did snow a couple inches on me. The green is popping out on everything, the lawns are growing about a foot a week, I swear, and it is the wet season, raining regularly. Sure there is smoke in the air, but that is because everybody who wants to clean up around their place is burning now, when there is no danger of starting the woods on fire, and everything they are trying to burn is usually so wet it smolders rather than burns.
    August is our fire season, with occasionally July and September thrown in, that is when it is hot, and at least some years, drier than a chip. Right now you couldn’t start a forest fire with a tanker load of diesel.

    Intellectually I understand that in the Southeast, and even in places in Southern Idaho that fire can burn under the scattered trees and renew the ground without killing the trees. But I have always lived in forested country, there is NO grass under the trees to burn. It often full of underbrush that burns nicely, but regardless any fire that is going to burn enough to spread is going to kill every tree it comes to, fire is most definitely not “a good thing” in this part of the country. This isn’t to say that “slash burns” where you burn off all the slash left in a fresh clearcut aren’t a very good thing, but they need to be carefully controlled to keep them out of the trees. It certainly renews the soil and makes everything grow back, faster, lusher, and thicker; not to mention removing all the limbs, tops, and whatnot that make a real mess to try and walk through. In a couple years animals will flock to a clearcut that has been burned in multiples compared to those that haven’t. Not only is their more both feed and cover from the lusher plant growth, but the feed contains many more minerals and vitamins that they need.

    • You’ve hit one of the hard points: finding a baseline that works for each different region in terms of fire management. Trying to determine what things looked like in 1700, or 1800, in order to determine how to shape the forests into 1) what the Indians had, 2) what is best for wildlife 3) what is best for commercial forest use 4) “pristine untouched wild lands” or 5) all of the above [not likely] or 6) none of the above is a real challenge. And what works great in Georgia would be insane in southern California and laughable in the rain forests of western Washington. The book Forest Dreams, Forest Nightmares about forest management in the early 20th century is a great case study of what we didn’t know that we didn’t know.

      To propose a hypothesis, if you went back to the very earliest descriptions of your area, what do they say (or not say) about the forests and undergrowth? If the explorers commented on how easy it was to ride through the forest and the lack of undergrowth, for example, I’d wager that prior to Anglo settlement, the locals did burn things, or had some other method of brush control. Then in came people who really did not want fire in the woods, and after 50-60 years of “no burn” you have a situation with lots of brush and where any fire turns into a tree-eating blaze, rather than a creeping fire. Or it could be that the earliest accounts describe pretty much what you see today, perhaps with some different kinds of brush, and the Indians didn’t burn deliberately. Can the ecosystem clock be reset? Does anyone want to? How? When? And that’s just the first of the questions. 🙂 And it varies with what kind of forest you have, what you want from it, and what the weather is this year. Although its called “fire science,” I suspect there’s as much art as there is science.

      Down in New Mexico there are two fire seasons, roughly defined. The first is in eastern NM on the short grass steppe and it runs from Feb-March through late April, or until the first rains start and the grass greens up. In the mountains it is July-Sept that gets exciting because of the lightning from the monsoon season. Not that storms (and fools) check the calendar, but yes, when you have 4′ of snow on the ground, it’s kinda hard to get things to ignite.

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