Leaf colour in autumn

[Anne Heise]

Can you say more about how anthocyanin production would be a by-product 
of 'mineral mining'? I don't get that.

We have been doing crude paper chromatography on the red maple outside 
our building this fall.  The red pigments definitely were not there 
before the leaves turned.  The yellows were there, of course.

Anne Heise
Washtenaw Community College
Ann Arbor MI