alt Hacker NewsWhat would you call it?
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There seems to be a lot of things that come together to make it work, but it's basically sucking not pumping. The term to google is Transpiration.
It's a bit like a siphon effect with water evaporating from the leaves creating low pressure internally which draws more water up, and the reason it's able to pull a whole column of water up is because water molecules stick together to some extent via hydrogen bonds.
Given that evaporation is what is driving it, I wonder how that works with evergreens with low evaporation - I guess it's basically a replacement system, so you only need to pull what you evaporate.
They do wave in the wind, and evolution is likely capturing some of that motion for work.
“Trees contain lots of thin, hollow vessels and they suck water upwards by creating low pressure at the top,”
So sucking / pulling?
Not that it really matters, but the article also refers to it as “drawing water to the top”. That seems more representative of reality than “pumping water from the bottom”.