>>> Lawrence Kestenbaum <[log in to unmask]> 26/08/99 1:10:53 >>> wrote:

"...how high can ivy go on a building?  If unchecked, would the Doubletree become completely covered?  The World Trade Center?"

The boring answer is that it will be limited for the same reasons that trees do not grow to 300m.  The hydrostatic and diffusion pressures required to draw water from the roots to the uppermost leaves are enormous, and as such, tall trees and vines operate as incredibly powerful pumps.

I cannot remember the details (knew I should have paid more attention in my botany lectures), but that will be the limiting mechanism.  Maximum height ... why don't we have a sweepstake on it, and get somebody to check it out in five years time to see how it has progressed!

My bid ... 9 floors.

Cheers

david