The transpiration of water at negative pressures in a synthetic tree

  title={The transpiration of water at negative pressures in a synthetic tree},
  author={Tobias D. Wheeler and Abraham Duncan Stroock},
Plant scientists believe that transpiration—the motion of water from the soil, through a vascular plant, and into the air—occurs by a passive, wicking mechanism. This mechanism is described by the cohesion-tension theory: loss of water by evaporation reduces the pressure of the liquid water within the leaf relative to atmospheric pressure; this reduced pressure pulls liquid water out of the soil and up the xylem to maintain hydration. Strikingly, the absolute pressure of the water within the… 
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