Some of the willows next to the river by Silbury are pretty old, one was down across the river this year there have been some terrible storms bringing trees down. This is a photo of an old pollarded willow there..

http://www.themodernantiquarian.com/post/64685

This other photo shows how the branches of the willow at the spring are starting to bend down and rest on the ground, the heavier they become the more easily they will break. Same with topheaviness in a tree, strong winds will pull the tree down and the roots out of the ground....

http://www.themodernantiquarian.com/post/64686/images/swallowhead_springs.html..

Love trees so I tend to photograph them a lot - but they do need a bit of TLC now and then ;)