Gravity-defying trees explained by Newton

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Gravity-defying trees explained by Newton

How do towering trees like redwoods defeat the pull of gravity to bring water up to their leaves? Isaac Newton, the father of gravity himself, came up with an explanation that is not too far off from the current scientific wisdom, according to an article published online today in Nature Plants. The arboreal feat stumped scientists until more than 200 years after Newton penned his botanical musings (shown above) in an unpublished notebook he used in the 1660s. Newton suggested that light knocks away water particles from fluid-filled pores of the plant and “by this meanes juices continually arise up from the roots of trees upward,” he wrote. This bears a resemblance to the modern-day explanation—continuous chains of fluid form in the pores of the plant that stretch from root to leaves, aided by surface tension and the liquid clinging to the pore walls. Evaporation of water at the leaves pulls the chain of fluid up to the treetop. Although he didn't quite get the details right, one thing's for sure—Newton was no sap.

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