Trees can rightly be called masters of microfluidics. In the stem of a large tree, the number of interconnected water transport conduits can exceed hundreds of millions, and their total length can be greater than several hundred kilometers. Furthermore, on a sunny day, a tree can transport hundreds of gallons of water from the soil to its leaves, and apparently do it effortlessly, without making a sound and without using any moving parts. On a global scale, the movement of water through plants makes a major contribution to the hydrologic cycle by providing the principal pathway through which water moves from the soil to the atmosphere.
The physics that underlies water transport through plants is not exotic; rather, the application of that physics in the microfluidic wood matrix results in transport regimes operating far outside our day-to-day experience. In this Quick Study, we seek to dispel some of the confusion...
