Comment by hagbard_c

> It is highly unlikely, at least in the species I’m familiar with, that a tree will just fall over. > > Evolution tends to select against that kind of thing.

This is correct when the trees are bordered on all sides by more trees. On the forest edge - which is what this seems to be - things tend to be different though and the occasional tree does fall due to storm, rock slides, wildlife activities, water erosion and more. Especially when the forest edge is relatively new, i.e. the bordering land has been cleared somewhere within the last 40-50 years these edge effects can be sizeable. Eventually the forest edge thins out once the larger trees have all fallen to create a more gradual progression from open land to forest and there will be fewer large trees to fall on bordering land.