What is the adaptive value of the leaves of aspen trees quaking?

Howdy aspenlover-ga,

This San Francisco State University's Department of Geography article titled
"Biogeography of Quaking Aspen (Populus tremuloides)" as written by Douglas
W. Johnson explains the adaptive advantage that the flutter or "quaking" of
leaves gives the aspen tree, in a reference to Steven Vogel's Natural History
article "When leaves save the tree" from 1993.
http://bss.sfsu.edu/geog/bholzman/courses/fall99projects/aspen.htm

"The characteristic flutter of aspen leaves is the result of stems that are
flat in cross-section rather than round. This adaptation gives them strength
in the vertical direction while allowing them to twist flexibly in the wind.
In a high wind, the leaves clump together in a manner that reduces air drag,
the horizontal force that can break trunks.  This feature may help aspen
survive storms (Vogel 1993).
...
Vogel, Steven. [September] 1993. When leaves save the tree. Natural History,
102(9):48-63."

If you need any clarification, please feel free to ask.


Search strategy:

Google search on: aspen tree leaves adaptive OR adaptation advantage
://www.google.com/search?q=aspen+tree+leaves+adaptive+OR+adaptation+advantage

Looking Forward, denco-ga - Google Answers Researcher

My aunt, who was leading the query from our cabin in Colorado, has a
Master's in Geography from Berkeley and sees this as yet another
validation of geographer's inate supremacy! Go geographers!

I am in the mountains (well, actually, high plains desert) of Colorado
myself, so I am well familiar with the dance of the aspens.  Glad to be
of help, and thanks for the 5 star ratig, aspenlover-ga.  Greetings to
your aunt as well.

Looking Forward, denco-ga - Google Answers Researcher