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Comment by brabel | Hacker News Reader

> Why is forest cover so small in the UK? About 5000 years ago, people started cutting down forests to use the land for agricultural use.

Iceland used to have 25% of its territory covered in trees... until the vikings came, some time in the 900's. Now, it's nearly entirely devoid of trees.

https://www.geographyrealm.com/icelands-long-road-to-refores...

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IIRC this is attributed to the fact that the Vikings came to Iceland from Scandinavia via Scotland, a place with very thick soils capable of regenerating forests.

Superficially Iceland looked forested like Scotland, so they continued their existing animal grazing practices, which along with logging then destroyed the thin topsoil layer of Iceland.

I think it was Jared Diamond who summarized it like that, but in the context of Greenland, where the Viking immigrants suffered and even worse fate, but the patterns are similar.

Iceland certainly does not have many trees outside of settlement areas. But I noticed this island in the middle of a river that was growing a little forest[1]. I thought at the time that it must be all the grazing of the numerous sheep and horses I saw, that kept the forest from returning.

[1]https://njarboe.com/iceland/IcelandTreeIslandSkogafoss.jpg

Nice! But the little island seems to be next to slopes on both sides, well protected from the elements... maybe that helps?!

Counterintuitively, the existence of a forest provides protection from the elements for the trees that make it up. Forests shape their own climate in other wonderous ways - for another example, they tend to make their biome more humid.

Turkey, Greece, and the Eastern Mediterranean generally also used to be forested, until people came with goats.

The impact of sheep is under estimated. On Dartmoor in the UK sheep roam freely and there are very few trees. However, there are pockets of fenced areas that are thickly grown with upland oak and ash that would have presumably been what the whole moor would have had.

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