Why do some trees grow crooked?

There are a number of theories as to how trees in the Crooked Forest, Poland, have grown with strangely bent trunks.


Asked by: Milly Rees, Leicester

Trees normally try to grow with their trunk vertical, to provide the strongest support for their branches. But the Crooked Forest in Gryfino, Poland, has 400 pine trees, each with a 90° bend in their trunk.

The trees were all planted in the 1930s, when Gryfino was part of Germany. After WWII, the native German populace was expelled and the town was resettled by Poles, so none of the locals know why the trees began growing like this.

Various natural or accidental explanations have been proposed, including heavy snowfalls and damage from advancing German tanks. Yet none of them account for the very uniform bend, nor the perfectly normal pine trees growing right next to them. The most likely explanation is that they were deliberately bent to form curved timbers for furniture or ship-building.

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