daves@hp-pcd.UUCP (03/07/84)
As it was once explained to me, most trees have a thin layer of special cells that form between the leaf and the branch. When it is time for the leaf to fall off, this layer dies and the leaf drops off easily. Due to a genetic defect, oaks lack this cell layer. That is why it seems to take forever for the leaves to fall, and why I seem to find myself raking the leaves from my neighbors trees all winter long. --Dave Serisky ([hplabs!]hp-pcd!daves)
mik@siemens.UUCP (Michael Rissman) (03/17/84)
Oak trees do not shed their leaves until the Spring. What is the reason oaks evolved that behavior? How does shedding in the Spring, or not shedding in the Fall, benefit an individual oak?
paulsen@wxlvax.UUCP (Bill Paulsen) (03/17/84)
The leaves on most all the red oak trees I've seen fell off in the fall.
duhon@ihuxj.UUCP (duhon) (03/19/84)
In northeastern Illinois some oaks keep some of their leaves until spring. This is often the case with a mild fall. I believe this is mostly due to callous tissue forming incompletely or more slowly between the leaf scar (twig) and petiole. You can notice this same "leaf holding" in many beeches (the oaks are in the beech family).