|MadSci Network: Botany|
I have noticed that the leaves of the tree aspen always are in motion, even in the weakest wind. It is easy to realize that the motion is due to that the stem is flat, not round as on "normal" trees. It takes more mass, i.e. energy, to build a rectangular stem than building a round one, to the same strength. That is one disadvantage with squared stem. What is the purpose of the squared stem, is it to move the leaves, or what? What is the advantage of moving the leaves like this, and having a squared stem? What is the root-cause in the environment that have caused this evoution? Why haven´t other trees followed, or perhaps they have?
Re: Why are the stems of the leaves of the tree aspen rectangular?
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