Winter Photosynthesis?

Reader/commenter (and therefore hero!) Eric had a thought provoking comment after my sickeningly anthropomorphic post on what red and bur oaks think and feel during winter.  Eric writes/wonders:

"According to Phil Rutter (ed: Founder, American Chestnut Foundation and owner Badgersett Research Corporation), chestnuts and hazelnuts do a measurable amount of photosynthesis during the winter months using chlorophyll in the bark. I wonder, since oaks are related to chestnuts and hazelnuts (ed: All members of family Fagaceae along with beeches) - do they also photosynthesize during the winter months? And all those fractal branches would help expose more surface to sunlight and reflected light..."

I feel silly for not thinking about/pondering the same thing.  I read the passage in American Chestnut: The Life, Death and Rebirth of a Perfect Tree, by Susan Freinkel where Rutter says of chestnuts: "if you scrape half a millimeter under the bark it's green as grass. It's making sugar all winter long."

It's a great discussion topic!  One would think that a genus that includes many evergreen species (and some, as we have learned to our confusion, that are "half evergreen" and "partly evergreen") would have some mechanisms in place to get something out of every last drop of sunlight no matter what time of year.

1. What do you readers know about winter (winter of course meaning different things in different locations) photosynthesis beneath the bark of oak trees?  If you have trouble using the comments section feel free to email me at siemschristian (at) gmail (dot) com.

2. I'll do a little investigating myself, checking oaks of various species at different temperatures (today's temp quickly approaching absolute zero) and report my findings

3. Who knows, I might even crack a book to see what I can learn on the subject!

Thanks, Eric for a great subject to explore, and thanks as always for reading.