Months before devastating wildfires caused havoc in California, firefighters from across Europe headed to Sweden as authorities there struggled to extinguish several massive blazes. Officials in Sweden eventually got so desperate that they ordered an air force jet to drop a bomb in the middle of the wildfire's center to deprive the blaze of oxygen.
The strategy failed and Sweden's fires raged on. But just a few hundred miles away, in neighboring Finland, officials worried about a far different problem: not enough wildfires. "From nature's point of view, the diversity of species and habitats suffers from too few fires," the Finnish Forest Association concluded.
In Sweden, officials were stymied by their neighbor's luck: weather maps showed that both countries suffered under the same rare extreme heat this summer.
Viewed from space, the differences appeared striking: As all of Finland's neighboring countries, including Russia, battled massive blazes, the skies over Finland were smoke-free.
But it wasn't really luck, Finnish researchers soon let everyone know. Instead, Finland has one of the world's most successful strategies in countering wildfires that is now being more closely examined.
Over the weekend, Finnish President Sauli Niinisto saw himself forced to clarify that this strategy does not consist of raking, however. He was contradicting his U.S. counterpart, President Donald Trump, who said Saturday as he was touring California's wildfire areas that Finnish authorities "spent a lot of time on raking and cleaning and doing things, and they don't have any problem."
"You've got to take care of the floors. You know the floors of the forests, it's very important," Trump said.
The Finnish president confirmed having discussed wildfire prevention with Trump but rejected the suggestion that raking ever came up. The forest service in Finland carries out controlled burns of the forest floor, mostly to clear away underbrush and also promote new saplings.
Researchers aren't sure if the country's approach can really hold any lessons for California, however, given that parts of Finland are near the Arctic Circle with prolonged periods of rain and snow. Whereas below-average precipitation is still the exception in Finland, it has become the new normal in California.
Allowing some burns and clearing away undergrowth is also part of federal forest policy in California. In fact, some of the areas hit in the California fires burned 10 years earlier so there hadn't been a major build up of undergrowth.
The key factor in California's vulnerability to fires (and Finland's resistance) appears to be the weather. Finnish scientists predict the annual number of days with a wildfire risk to increase by perhaps as little as 10 percent by 2100. According to some estimates, wildfires may burn nearly 80 percent more area in California by 2050.
Finland does, however, offer an instructive example to its Nordic neighbors. It has managed to bring down the area annually destroyed by wildfires from about 247,000 acres a century ago to now less than 1 percent of that. That compares to nearly 62,000 acres lost this summer in Sweden.
"The difference between the two Nordic countries is not explained by vegetation or climate," Finland's Forest Association explained.