Surveying the devastation of California’s Camp Fire, President Trump suggested that America’s forests aren’t sufficiently raked. He went on to cite heavily-forested Finland as a place that knows its raking. (According to the Finnish president, Finns are accomplished yard maintainers but don’t rake forests). Whatever President Trump really meant, it does pose an interesting question. What is a forest fire like in Finland?

Comparing Finland to California is problematic to begin with. While Chico, CA, near the Camp Fire, is located at approximately 39.70 N latitude, Helsinki, the Finnish capital, is around 610 N. That puts Finnish forests squarely within the boreal Forest, or Taiga, biome. The Taiga is a ring of mostly evergreen forests that spans the Earth from around 500 N to the Arctic Circle. In other words, it’s a very different place from Northern California’s Sierra forests, which are comprised of mixed conifer and hardwoods, and the chaparral, the dry scrub forests found in Southern California.

So what is a boreal forest? As described by biologists M. Fauria and E.A. Johnson, much of the year the taiga is frozen, snowy, and cold, conditions that are not conducive to fires. As such, the boreal forest has a short fire season, lasting from May to August, peaking between mid-June and mid July. By August, burns decline rapidly. The unfavorable conditions limit the size of fires, although the infrequent large fires are responsible for most of the damage.

As much of the taiga is uninhabited, lightning is the primary source of fire. Most of these fires are crown fires, which burn rapidly across the tree tops, rather than fires that completely obliterate everything, as has been seen in the American West. The biggest risk factor for taiga fires is a particular climate pattern that causes spans of very dry air. Precipitation declines and fuel quickly dries out, increasing fire risk while these conditions last.

Given the vast, empty areas of the taiga, forest management has been limited. While decades of fire suppression in the American West allowed fuel to build up, increasing the severity of fires, suppression is mostly irrelevant in boreal fires. The sparse population also keeps the loss of property and life low.

There is a connection, however, between taiga fires and those seen in California. Just as climate change has been causing warmer and drier conditions in the American West, increasing the risk of devastating wildfires, high latitudes have been and are expected to experience even more dramatic temperature increases. The effects are already noticeable. The largest fires, once rare, are steadily becoming more common.  And if the taiga becomes warmer and drier, fires will be more frequent in those forests as well.