>The mechanism of flow is still poorly understood to the best of my
>knowledge, but what's being withdrawn are sugars (sucrose) and minerals that
>have been stored within xylem parenchyma cell over the winter, and which are
>now being mobilized in preparation for renewed growth.
Do the positive pressures generated this way have a role in refilling
tracheary elements that cavitated over the winter?
David J. Hicks djhicks at manchester.edu
Biology, Manchester College