'If a tree falls in a forest and no one is around to hear it, does it make a sound?'

​This riddle has always fascinated me. It's all about the 'observing' and the actual 'reality' of the event. To me, it does make a sound but there is no one there to actually experience the sound. Without anyone actually being there, there is no way of proving this. Although with insects, animals and birds around at the time of the falling surely 'they' would have heard the fall!! The only way of proving the incident is the fact the tree is no longer upright but is now on the ground. The occurrence has left a physical mark on the landscape; the tree is physically no longer in the ground, it has been ripped or snapped away from its original positioning!  
I also think about the wind and the 'sound' of the wind. We only hear it because of the structures; trees, buildings, valleys etc. that it blows through. Without them the wind would not physically produce sound?!!
It is the physicality of these happenings that intrigue me. The traces that nature leaves on the landscape. The physical recording of the passing of time and the ever changing elements. 

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