July 18 2019 12:00 AM

The island nation never recovered from the Viking invasion in the 9th century.

If you know anyone who really hates trees, tell them to take a trip to Iceland. According to a story in Phys.org., forests there are so rare and the trees in them so sparse that a common joke claims that if people ever get lost in their woods, they need only stand up to find their way.

The story says that Iceland, now considered the least-forested country in Europe, was once lush with forests. What happened? In short, the Vikings happened. When they left Norway and arrived at the uninhabited island at the end of the 9th century, birch forests covered more than a quarter of it. Just 100 years later, the invaders had managed to cut down 97% of those trees to build houses and clear grazing pastures.

A 2015 report by the United Nations Food and Agriculture Organization says forests now cover just 0.5 percent of the island’s surface. The lack of trees means there’s little vegetation to store water or protect the soil from eroding. Despite the country’s far northern locale, it’s mostly desert.

But the island nation is struggling to reforest itself. That’s been difficult because of its harsh climate and active volcanoes which periodically cover the soil with lava and ashes.

Reforestation efforts since the 1950s and especially the 1990s have restored some greenery, and the work continues — but not with native birch trees. “The problem with birches,” Adalsteinn Sigurgeirsson, deputy director of the Icelandic forest service is quoted as saying, “they aren't a productive species.”

Dozens of nursery gardens have been set up around the country to facilitate the reforestation efforts. In Kvistar, about 60 miles from Reykjavik, up to 900,000 pines and poplars are produced each year. The young trees are cultivated indoors for three months before being moved outside.

“Originally, they come from Alaska but now we have 30-, 40-, 50-year-old trees giving us seeds, so we collect that and we use that for forest seedlings production,” says Holmfridur Geirsdottir, a 56-year-old horticulturist and greenhouse owner in the story.

“If you are going to meet other objectives, like fast sequestering of carbon or producing timber,” he adds, “we need more variety than just monocultures of one native species.”

The new trees grow slowly, as the Icelandic soil is low in nitrogen. The average growth rate is only about one-tenth of that observed in the Amazon rainforest. Ironically enough, global warming is actually helping the situation. As Sigurgeirsson says in the story, “Warming appears to be elevating tree growth in Iceland, and therefore also the carbon sequestration rate.”

The Icelandic government has made reforestation one of its priorities in its climate action plan, according to the story. It identifies trees’ carbon uptake as one of the ways of mitigating climate change. Since 2015, between three and four million trees have been planted.