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Silvery white haze on newer roots?

Discussion in 'Issues, Disease and Pests' started by Greeng, May 24, 2021.

  1. Greeng

    Greeng Micro Nut

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    Location:
    New York
    Hi,

    Newish to orchids. Are these roots in trouble? They all started out solid light green, but they've slowly developed this silvery white haze in the last week or two.

    (Please ignore the dried/shriveled roots on the Schoenorchis; my first introduction to "must dry out before next watering...")

    IMG_0944.jpeg IMG_0943.jpeg
     
    J E likes this.
  2. Ray

    Ray Orchid Iconoclast Supporting Member

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    Location:
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    The white stuff is called “velamen”, is quite normal and consists dead cells that serve multiple functions.
    • It acts as a sponge to absorb water for the plant to then slowly take up.
    • It acts to insulate the inner part of the root from desiccation.
    • It traps nutrient ions so they cannot be washed away.
    I find that last aspect to be evolutionary genius. In nature, epiphytes get fed and watered every time it rains, but the concentration of nutrients is negligible, and they are only present in the rainfall for the first instant after the rains - often torrential - begin. Without that adaptation to “grab” them, the continued rains would wash any nutrients the plant absorbed initially.
     
    Greeng, J E and scruffy like this.
  3. J E

    J E Jaime Escobedo

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    Yes ditto on what Ray said, that is normal and very important it's called velamen, it acts as a moisture barrier for the root keeping it from drying out when the plant is in the "dry" part of the wet dry cycle.
     
    Greeng likes this.
  4. Greeng

    Greeng Micro Nut

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    Thanks both!
    Fascinating indeed the ability to trap ions in this scenario..! Like I needed another reason to continue this micro orchid journey.:cool: