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Scouring Rush – Ancient Lineage Tracing Back 350 Million Years

11-26-14 Scouring Rush 141 Scouring Rush (Equisetum hymale) belongs to a group of non-flowering, spore-producing plants that are known as horsetails. The group is named after some of the species in it that are branched, and were thought to resemble the tails of horses. There are several species of horsetails, including Scouring Rush, that do not branch. Three hundred and fifty million years ago horsetail relatives dominated the understory, with some individuals growing as high as 100 feet.

Scouring Rush’s rough stems terminate in a pointed cone within which spores develop. Their evergreen, hollow stems are jointed (stem can separate easily into sections by pulling at joints) and their leaves have been reduced to small sheaths encircling each joint. Scouring Rush is often found near streams and ponds, and can form large colonies.

The stems of all species of horsetails contain silica. Those of Scouring Rush, as one might gather from its name, were bundled together and used as a fine abrasive for scouring pans. In addition, they were used for sanding wood and smoothing reeds for woodwind instruments.

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12 responses

  1. Louise Garfield

    This most curious plant is one of my favorites.
    Thanks for this and all your offerings throughout the seasons!
    Happy Thanksgiving.

    November 26, 2014 at 2:39 pm

  2. Rachael Cohen

    Scouring rush — or as we called it, reed rush — is still used to adjust woodwind reeds, at least it was as of the late 1970s and early 1980s, when I was at Kinhaven Music Camp in Weston, Vermont. The rush grew (and still grows) near the pond, and my clarinet teacher instructed all his students in how to collect and use reed rush to adjust commercially made reeds to our personal preference.

    My brother also constructed panpipes from hollow rush segments, but they weren’t very loud or euphonious.

    November 26, 2014 at 2:53 pm

    • Fascinating, Rachael! Thank you so much for this information.

      November 26, 2014 at 2:56 pm

  3. I always figured equisetum was inedible because of all the silica (we had huge swaths of equisetum around our old house). But then I noticed flocks of turkeys moving through, carefully nipping the fertile tips off them.

    November 26, 2014 at 5:16 pm

    • That is so interesting, Kellyann! I wasn’t aware they ate them!

      November 26, 2014 at 5:51 pm

  4. Jean Harrison

    I always assumed the name came from the sterile fronds which do resemble horse tails.

    November 26, 2014 at 6:22 pm

    • I think you may be thinking of Equisetum arvense, Jean. It is the most common horsetail with a sterile stem that is branched. (common name is Field Horsetail)

      November 26, 2014 at 6:54 pm

  5. Are they, or their ancestors, also the stuff of our ancient coal beds?

    November 26, 2014 at 7:57 pm

    • Exactly! The were in the coal deposits of the Carboniferous period.

      November 26, 2014 at 8:53 pm

  6. Marilyn

    Fascinating! Something else to examine more closely. Thank you.

    November 27, 2014 at 1:16 am

  7. We have lots of horsetails around here along the river. I love that they stay green all winter. Any bit of color this time of year is appreciated!

    November 27, 2014 at 4:14 am

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