Leaf Arrangement

Discussion in 'Plants: Science and Cultivation' started by Junglekeeper, Jun 6, 2017.

  1. Junglekeeper

    Junglekeeper Contributor 10 Years

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    I noticed there are stems on my olive tree that have different leaf arrangements - some are opposite while others are alternate. I didn't know it possible to have more than one arrangement in a plant. How common is this in the plant world?
     
  2. Daniel Mosquin

    Daniel Mosquin Renowned Contributor UBC Botanical Garden Forums Administrator Forums Moderator 10 Years

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    Uncommon, but it happens. There are several native Asteraceae that switch from opposite to alternate or vice versa as the stem elongates.
     
  3. Junglekeeper

    Junglekeeper Contributor 10 Years

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    That's interesting. It adds another element of uncertainty into identifying plants as leaf arrangement is often used in the process. What do you suppose is the benefit to the plant in changing up its leaf arrangement?
     
  4. Michael F

    Michael F Esteemed Contributor Forums Moderator 10 Years

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    It's deliberate, with malice aforethought, with the specific intention to confuse botanists.

    :-))
     
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  5. Daniel Mosquin

    Daniel Mosquin Renowned Contributor UBC Botanical Garden Forums Administrator Forums Moderator 10 Years

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    *whistle* It's a big topic. Things to consider: light capture, plant cooling, optimal temperatures in different parts of the plant for different physiological processes, proximity of photosynthesizing areas (and magnitude of such) to areas of development, likely more than that!

    Here are some examples:

    Leaf size and angle vary widely across species: what consequences for light interception?

    On the mystery of the golden angle in phyllotaxis - KING - 2004 - Plant, Cell & Environment - Wiley Online Library
     

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