Thanks for the summary. Just one question- I've always been under the
impression that it was the Mg ion in the center of each chorophyll
molecule that is the primary object of recycling by trees before
leaf-drop. Since Mg++ occupies essentially the same position as Fe++ in
hemoglobin, its lack would cause the plant equivalent of "iron-poor
blood"...although I'm sure N is worth retrieving as well. Do any of the
plant physiologists out there have any comment on the relative scarcity of
Mg and N, and of their fate and storage over winter?
Char A. Bezanson (bezanson at stolaf.edu)
School Nature Area Project
St. Olaf College
Northfield, MN 55057