Tuesday, December 4, 2012

Leucobryum glaucum - the pincushion moss

   The other little moss that was peeking out of the birch bark, which i didn't notice right away, was a little piece of Leucobryum glaucum. this distinctive moss was one of the first mosses i learned as it's easily identifiable.
One of the few mosses with a common name...it goes by 'Pincushion Moss' or even better...'Mother-in-Law's cushion'.  It can grow into quite large rounded cushions, large enough to sit on...and it looks ever so cushy and comfy...so, if you don't actually like your mother-in-law, you invite her to rest her feet and have a seat....what you don't tell her, is that this moss, like many of the sphagnums is really good at soaking up water like a sponge, so when you sit down on it, you will end up with a wet bottom.
  the thing that makes Leucobryum so distinctive, is also the reason why it soaks up water...it's leaf contains a great number of empty cells...The leaf has a midrib that is so broad that it doesn't look like a midrib at all anymore...it just looks like the leaf is thick and fleshy. When the plant dries out, it's color changes from green to a pale whitish green or light blue-green that is very distinctive.

a small clump of moist Leucobryum

Notice the color when it's dry

The cushions of Leucobryum are actually many separate plants all crowded together. the plants in the center of the clump continue to elongate which can make it form a nice hemispherical cushion.

this is a scan of a piece of Leucobryum taken from a large cushion

a Leucobryum leaf - the whole center is made up of a thick midrib
Leucobryum loves moist or even swampy woods and grows on humusy soil, often where stumps have completely rotted to the ground. Even though it prefers these moist areas, it can also be found in much drier areas as well. But almost always in acid areas.

Here is a nice patch of Leucobryum growing up next to McLeod pond in Colrain, MA.
Now, doesn't it look comfy to sit on??
Next time you're out in the woods, keep your eyes open for this lovely, common moss.


  1. Check out in woodlands (at least in the UK) the very very similar Leucobryum juniperoidium

  2. Very nice. Thank you. I'm interested in mosses for terrariums and pincushion is the only one I've gotten to last for years in a terrarium without looking too straggly over time. Do you know any others? And, do you know the best way to propagate pincushion moss?

    A particular curiosity is the smallest flowering plant that I know of for terrariums, Sinningia Pusilla, only grows well in moss. Its very odd. I've tried growing it from seed in otherwise ideal conditions and it simply doesn't thrive. But, it if find the right spot in a clump of moss, it virtually springs-up, thrives and flowers.

    I haven't seen this yet in pincushion but am hoping it will.

    Still getting a stack of stories for my blog to go live at some point.