While hiking on the northern Idaho-Montana border, I encountered a large area where virtually every tree is bent at the base in the downhill direction. Only the very largest and very smallest trees are straight. What could cause this?

enter image description here enter image description here

  • 1
    $\begingroup$ Avalanche? Or just a heavy accumulation of snow bending them towards the ground one year. I could find you some hereabouts that are bent into U-shapes, or even S-curves. $\endgroup$
    – jamesqf
    Commented Jun 29, 2015 at 5:29
  • 6
    $\begingroup$ Forgot to remove the fisheye lens? $\endgroup$
    – canadianer
    Commented Jun 29, 2015 at 6:04
  • 4
    $\begingroup$ This case is much different, but you might find it relevant: Crooked Forrest. $\endgroup$
    – dtldarek
    Commented Jun 29, 2015 at 15:29
  • 1
    $\begingroup$ Prevailing winds, you see a lot on the coast. $\endgroup$
    – RedSonja
    Commented Jun 30, 2015 at 10:20
  • 2
    $\begingroup$ Also see,the Dancing Forest en.wikipedia.org/wiki/Dancing_Forest they think it might have been caterpillars. $\endgroup$
    – RedSonja
    Commented Jun 30, 2015 at 10:22

1 Answer 1


The phenomenon in question is probably related to geotropism.

If the hill soil is "on the move" it will cause the bend on the trees -

If the soil in a slope is moving downward, the trees on this slope will tip downward. As the tree continues to try to grow upward, the trunk will show a curve. The degree of bending could indicate the rate or amount of movement of the soil.

enter image description here


  • 12
    $\begingroup$ This was a surprisingly interesting question and answer. $\endgroup$
    – canadianer
    Commented Jun 29, 2015 at 11:39
  • $\begingroup$ @canadianer :) thanks, nice to help to community %) $\endgroup$
    – Ilan
    Commented Jun 29, 2015 at 17:38

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .