When do leaves stop producing?

[Treeaddict]

When leaves start changing color, are they still producing? Is the tree considered dormant before the leaves fall? I’m thinking the tree goes dormant, leaves die, turn color, become brittle brown and then drop? The leaf color is in response to the tree shutting down chlorophyll production?

 

[flushcut]

Oh boy you just want to know it all, don’t cha. May I suggest Shigo’s New Tree Biology.

 

[Marc-Antoine]

I don't have a precise aswer. What I can tell is that the leaves just don't die like that when the tree becomes dormant. Actually it's a controled process of putting the tree in shelter mode. Dormance of the tree and fall of the leaves are two parts of this, among others like relocating nutriments stocks, modifying the cells' content to sustain the dry/cold/frost and activating the specialized areas separating the twigs from their leaves (or even the twigs from their limbs for some species).
The leaves aren't caught by surprize and dumped away like a useless tool.

 

[Bermy]

The change of colour is as a result of green chlorophyll being broken down and stored, thus revealing the other colours. Once this process (and others) is complete, the leaves lay down a 'barrier layer' and drop off, (leaf senesence) hence the leaf scar that is sealed.
It it a whole planned and set process, check 'phenological cycles of trees'

 

[frans]

…and then the leaves breakdown on the ground and supply nutrients to the tree via composting.
Nothing is wasted. (Until some rabid landscaper does their work with the blower)

 

[Bermy]

Oh boy Frans, don't get me started on 'the cleanup ' with blowers....

 

[Bodean]

Leave the leaves. Circle of life… the dead feeds the living… no one rakes a forest.