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Updated: Jul 12, 2026

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A Venturi Effect Can Help Cure Our Trees
Published on: October 1, 2013
The spinning rotation of ash and tulip tree samaras
Abstract:
Ash and tulip tree samaras rotate on their long axes as they fall, as well as spin around like maple samaras. They descend faster than would maple samaras of the same size and weight and much faster than would zanonia samaras, but they are very stable, which may explain their evolutionary success.
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