TREE

To the woods with my favourite ten year old.  These days he finds den building and tree climbing a trifle passé.  Now it is all about the big questions:

'How do trees know which way to grow?' 
'Why do trees stay alive after they're chopped down?'
'How do trees talk to each other when they don't have brains?'
'What will happen when there are no more trees?'

 ...and (extra)...

'What causes reflections?'