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Common Polypody Spores Dispersing

10-27-15 rock polypody 057Common polypody (Polypodium virginianum), also called Rock Cap Fern, is a perennial plant found most often growing on rock surfaces usually in moist, shady woods. Being a fern, Common Polypody reproduces by spores. Structures that produce and contain spores (sporangia) are found on the undersides of the fertile frond leaflets. The sporangia form round clusters called sori. The sori of Common Polypody are orange-brown when mature and lack the protective covering (indusium) that some other fern species have. At this time of year, the mature spores are being dispersed by the wind.

The ability of Common Polypody to tolerate extreme desiccation (the leaves roll up when moisture isn’t as available, and resume their normal state when moist conditions return) means it is well adapted to the extreme moisture fluctuations of rock surfaces. Its evergreen fronds are consumed in the winter by Ruffed Grouse, Wild Turkey, and White-tailed Deer.

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6 responses

  1. Cheron barton

    🤓 enjoy!

    Sent from my iPhone


    October 27, 2015 at 8:11 am

  2. Hi Mary… I have encountered this type of fern off & on my entire life when in the woods.
    It is all around my property as well.
    I am curious & wonder if it draws it’s moisture from the green moss growing along side of it.
    BF… WGF Studio53

    October 27, 2015 at 9:11 am

    • I honestly don’t know, Bill, but you could very well be right.

      October 27, 2015 at 1:55 pm

  3. I too have seen this in our NH woods, and wondered. I think you may have meant Polypody Virginianum commonly referred to as Rockcap Fern, although I never knew this! Just googled it and amorphum refers to a western relative. Just curious, how do you pronounce it, polly-paw’-dee or paw-lip’- a-dee? (Hope my phonic description is clear.) Thanks for this clarification, evergreen ferns are so lovely!

    October 27, 2015 at 1:23 pm

    • You are so right, Helen, I meant to write “virginianum” as the species – I have no idea how it got switched! Thank you so much for bringing it to my attention. I pronounce it “paw-lee-PO-dee” but I could well be mispronouncing it!

      October 27, 2015 at 1:54 pm

  4. One of my favorite ferns – always makes me think of hair ont op of rocks.

    October 28, 2015 at 10:19 am

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