How do tree roots “drink” water? What causes vacuum pressure to pull water up into the tree?

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How do tree roots “drink” water? What causes vacuum pressure to pull water up into the tree?

In: Biology

There is no vacuum pressure. Fluids in plants move due to [capillarity](https://en.wikipedia.org/wiki/Capillary_action), just like a paper towel will draw water from a glass regardless of its orientation.

The vacuum (also called negative pressure) is created by evaporation from leaves at the top of the plant. There is also positive pressure that is created by having different concentrations of things like sugars, which moves water into and around the plant by osmosis.

[https://en.wikipedia.org/wiki/Xylem#Main_function_%E2%80%93_upwards_water_transport](https://en.wikipedia.org/wiki/Xylem#Main_function_%E2%80%93_upwards_water_transport)