Interesting how Oak trees hold onto their leaves

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PA. Woodsman

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It's interesting that here it is almost time for the trees to start budding again, yet most Oak trees still have a decent amount of their old dried brown ones hanging on. I wonder why they do this when most other species drop all theirs?
 
My oaks do that too but Beech trees hold their leaves even more than oaks. Its a pain in my woods because when I am gun hunting in November all my Beeches still have their leaves:censored:
 
...I wonder why they do this when most other species drop all theirs?

I've often pondered that question myself. The best guess I could ever come up with is perhaps the old leaf protects the bud of the new leaf over the winter, then when the new bud opens up it knocks the old leaf off. I've never bothered to actually research the subject, though.

We had some variety of maple at our house in Kansas that would hold leaves all winter too. Some of the dead leaves would even hang on all through the summer.
 
I was noticing the same thing a little while ago. I don't seem to remember them hanging on as much last year. Mostly it seems to be the white oaks in my yard. I have an elm tree too that holds onto them, and that's the one I always noticed stood out from the rest for hanging onto them each winter. Like I said, not sure why the oaks in the back seem to be holding on more this year.

Being that you live pretty close to me, I'm sure you could agree that we've had some pretty decent winds over the last couple of months. Interesting how they can hold on so well despite the wind force.
 
best i could find on the subject:

The reason why oaks and beeches hold onto their leaves well into the winter is not completely understood. I read many years ago that one reason the leaves fall late is to protect the mast, the fallen acorns and beech nuts, from animals that would eat them.


http://www.seacoastonline.com/apps/pbcs.dll/article?AID=/20071206/SPORTS/712060338/-1/SPORTS11

or.....

Why they hold on is a mystery, but there are at least two possibilities as to how they do it.

When fall comes, deciduous plants move all of the carbohydrates from their leaves back into their woody parts -- trunk, branches and roots. A hard tissue called the abscission layer is then formed at the point where the leaf stalk meets the stem, effectively closing the door between leaf and plant, and causing the leaf to fall off. It may be that the abscission layer in oaks and beeches isn't as thick as it is in other trees, and the leaves just hang on longer, hoping that the tree will hear them knocking and open up, or at least send out a warm sap toddy.

Another possibility is that the bundle of vascular tissue between the leaf stem and the twig is larger or stronger in these trees, and that it just takes more time and effort to break it.

Either way, these trees are always stubborn, always the last to let go of last year.


http://query.nytimes.com/gst/fullpage.html?res=9B06E4DE1331F937A25752C0A96F958260
 
I believe that trees hold their leaves longer in town & cities because temps stay warmer longer into the fall because of the "thermal flywheel" effect of concrete and asphalt masses located in them. Can't prove it, just a pet theory of mine. :) See more leaved trees later in the season in urban areas rather than in rural.
 
native beliefs

Native americans thought of oaks as the leaders of the plant world, they are strong and hold on to life no matter what. This is why they keep their leaves, natives used oak medicine for people that seemed to no longer want to hold on to life and felt like giving up. It was also used for people who needed an extra boost of strength to get through a difficult time in their life. -Native folklore
 
Our Red Oak's have lost their leaves in the fall. However, the White Oaks still have the brown leaves. Pin Oaks still have a little still hanging.
 
A Dendrology professor I knew had a theory, he thought oaks(beeches too) may have been evergreen(like live oak)and are now slowly evolving into decidous trees. Not what I said, but who knows?
 
Marcescence

Marcescent is the term used for a tree that holds onto its leaves through the winter. It's caused by the tree not forming an abscission layer, which would cause the leaf to fall off. Most deciduous trees form it in the fall, unless it's an early freeze. If an are gets an early freeze, other species of trees may hold onto their leaves longer as well. Flowering plants (and trees) do this with flowers after fertilization, fruit trees do it to fruit, when the fruit is mature and most trees do it yearly with their leaves, in the fall. Evergreens on the other hand do it all the time, causing them to shed needles all year round.

Why? I have no idea.

Just figured I'd add that to the discussion.

Mark
 
Juvenile oaks and fast growing shoots on mature oaks seem to hold the leaves the longest.
When I look out the window well, I can see leaves on an Oak in the yard, still hanging on. If I wasn't' scared to go outside, I'd pull one off and study the leaf scar.
 
Just another theory

I have noticed that the oaks in our area, particularly the pin oaks, hang onto about 1/2 their leaves until budbreak in the spring.

The leaves that remain attached all winter are usually closer to the center of the tree, suggesting to me that the point of separation from the branch was either not completely finished when the tree shut down in the fall, or that those leaves were somehow more strongly attached and simply didn't fall off until forced out by the spring growth.

The terminal branches are almost always bare, and I suspect that is because they are the first to lose sap flow in the fall.

Every spring we have lots of yard cleanup when the buds come out.
 
sweetgum

I have a doggoned sweetgum tree that holds it's leave really late in the year. it does lose them but a minimum month after the rest of the trees. and those :censored: round seed pods! :angry2: :angry2:
 
Marcescent is the term used for a tree that holds onto its leaves through the winter. It's caused by the tree not forming an abscission layer, which would cause the leaf to fall off.d.
That is key.

It is not that the leaves are 'holding on better' than other trees (Think about strong summer winds...all trees hold their leaves fine through most of those). It is that the trees haven't 'released' their leaves - that is a process that the tree has to do so it forms the abscision layer - they don't just "fall off" on their own on any species.
 
ozarktreeman said:
...tops already budding...

LOL! And around here in my back yard I still have 12"-14" of snow and right now it's 1° outside.
cold.gif


StihlRockin'
 
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