wrote in message
...
On Tue, 14 Nov 2006 17:20:42 +0100, "JennyC"
wrote:

It breaks down in sunlight........:
http://scifun.chem.wisc.edu/chemweek.../fallcolr.html

Thanks. That explains the Autumn colours well. What about evergreens,
why don't they lose chlorophyll?

Steve Wolstenholme Neural Planner Software
EasyNN-plus. The easy way to build neural networks.
http://www.easynn.com



You know I've never thought about that !!!!!!!!!
You've started me of now............


The evergreens-pines, spruces, cedars, firs, and so on-are able to survive
winter because they have toughened up. Their needle-like or scale-like
foliage is covered with a heavy wax coating and the fluid inside their cells
contains substances that resist freezing. Thus the foliage of evergreens can
safely withstand all but the severest winter conditions, such as those in
the Arctic. Evergreen needles survive for some years but eventually fall
because of old age.
(http://www.na.fs.fed.us/spfo/pubs/mi...ves/leaves.htm)

and some more...........
http://www.newton.dep.anl.gov/askasc...0/bot00200.htm
http://www.ccmr.cornell.edu/educatio....html?quid=983

Jenny