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Distinguishing the Hornbeams

1-23-17-hophornbeam-img_5028There are two trees, both in the Birch family, which, due to the similarity of their common names, are occasionally mixed up with each other. One is known as American Hornbeam (Carpinus caroliniana) and the other as American or Eastern Hophornbeam (Ostrya virginiana). Due to the hardness of their wood, they also both go by the name Ironwood, adding to the confusion. A perfect example of when Linnaeus’s binomial system, which gives each species two scientific names, one of which is unique to each species, is helpful.

While the fruits and leaves of both species are superficially similar, their respective bark is very different. Carpinus caroliniana’s bark resembles flexed muscles (see ), earning it yet another common name, Musclewood, while Ostrya virginiana’s bark (pictured)  has a “shreddy” appearance, with the bark broken into small, narrow plates which curve away from the trunk. Look for C. caroliniana in valleys and along streams, and O. virginiana on well-drained slopes and ridges.

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11 responses

  1. Alan M Stoops

    Because of the name confusion, I refer to these as “musclewood” and “hop-hornbeam”.

    January 24, 2017 at 7:38 am

  2. I love both of these trees and plant them for clients. Up here in Ontario Canada, there is a Ostrya virginiana that the Baltimore Oriole’s come to and feed on every spring. Both are understory trees which makes them an ideal size for around larger trees. Also it adds to the bio-diversity of the area where I plant them.

    January 24, 2017 at 7:58 am

  3. Kathie Fiveash

    Carpinus caroliniana is the preferred food for the beavers at my local lake. Just about all of them near the shore have been cut down.

    January 24, 2017 at 8:13 am

    • Wow. I didn’t realize their teeth were that strong!

      January 24, 2017 at 9:23 am

  4. Patsy

    So pleased to see this post. I have been stumped by this issue for years. I see “musclewood” in the woods and know it’s “ironwood” and then my wood guy delivers wood and calls the shreddy logs “ironwood”! Now I get it! Thanks, Mary.

    January 24, 2017 at 8:18 am

  5. Cheron barton

    ❄️BIG❄️❄️ in your world!! Stay safe!!

    Sent from my iPhone


    January 24, 2017 at 9:41 am

  6. Edward MacDowell

    The inset on your blog about the hornbeam pictures the blossoms, but no reference is made in this piece to the common name New Englanders often use, the “hop hornbeam.” This name comes from the resemblance to hops used in the brewing of beer. Do both trees have the same blossoms?

    A second question relates to the similar names given to the beech called “muscle beech” and the hornbeam called “muscle wood.” Am I confused on this or are both these trees hornbeams and neither a beech?

    January 24, 2017 at 10:28 am

    • Hi Edward, The inset is actually a photo of the fruits of O.virginiana, which do, indeed, look like hops and are responsible for one of its common names. C.caroliniana‘s fruits are similar, but three-lobed. C. carolinia is also known as Blue-beech (in addition to Musclewood, Ironwood and American Hornbeam).

      January 24, 2017 at 10:55 am

  7. Leah D Basbanes

    Looks like a sapsucker visited that tree!

    January 24, 2017 at 10:34 am

  8. Viola

    Thanks so much for that last sentence which gives the habitats where these two trees are apt to grow. I’ve not seen that spelled out before; it will be a big help when out in the field. Happy New Year, Mary. Keep up the great work!

    January 24, 2017 at 3:25 pm

  9. Mary Sloat

    Thank you for clarifying the two trees. I have always been confused about the one that grows on Mt. Prospect in Lancaster.

    January 24, 2017 at 4:00 pm

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