It always is amazing to think about the forces that are required to push water up the really tall trees. The forces involved are enormous and it is amazing that natural phenomenon without massive pumps and large amounts of energy are not involved!
The video below seeks to understand the forces that make water move up the trees is amazing. They have sequentially tried to work out whether it is osmotic pressure pushing the water up, or the capillary surface tension or suction generated by evaporation at the top.
It turns out that the suction force generated at the top of a really tall tree is responsible but it is still amazing that the leaves continue functioning and all remains functional at different temperatures, pressures and humidity conditions. Or maybe it is the specific environment that is enabled the phenomenon to occur and supports the tall trees.
Watch the video to learn more:
{youtube}BickMFHAZR0{/youtube}
