Bamboo Identity Crisis

 A friend gave me a bamboo to test, sold under the name Yushania confusa. This modestly sized plant is said to reach a maximum height of 6 feet, growing from a base only 2-3 feet wide, and arching up to 9 feet wide without pruning to keep it more upright. It's described as "tightly clumping." 

The plant being sold as Yushania confusa

Hm, a tightly clumping Yushania? That doesn't sound right. Despite one nursery describing the genus as including both "tight clumpers" and "semi-runners," (which may have been true at one point during the taxonomic shuffle) the current definition of the genus only includes those species with extended rhizome necks, the "semi-runners." So a tightly clumping bamboo can't be a Yushania, right? 

Clearly something is off. Some digging lead me to the botanical description for the real Yushania confusa, the full text of which is available here. It describes the rhizome necks as ranging from 10cm to 40cm, or about 4" to 16". That doesn't sound tightly clumping, now does it? Culm internodes purple spotted, with persistent culm sheaths? Auricles absent. None of this matches the plant I was given. Further inspection would undoubtedly provide more evidence, but the rhizome length alone is enough to tell me this plant is not Yushania confusa. I doubt the real Yushania confusa is even in cultivation outside of China.

Close-up of leaves, with the slightly darker auricles visible in a couple spots if you look closely.


What, then, is the identity of this small clumping bamboo? Further internet digging led me to the catalog of Kimmei, a renowned bamboo nursery in the Netherlands responsible for introducing the majority of new species from China in the last two decades, and from Europe these plants make their way to America. In the catalog is a plant they call Fargesia 'Rufa' 'Dwarf', with the note that it has been in cultivation under the name Yushania confusa

Foliage and sheaths do indeed look much like the commonly available 'Rufa'

Here, now, the mystery appears to be solved. The name provided by Kimmei still has some issues. For instance, a plant can't have two cultivar names, so 'Rufa' 'Dwarf' doesn't work. Now, here's another bit of confusion: the plant introduced as Fargesia rufa, or Fargesia 'Rufa' was determined to be the true Fargesia dracocephala. The plant initially introduced as Fargesia dracocephala was determined to be another species, F. apicirubens. So, the standard form, 'Rufa', is now known as Fargesia dracocephala 'Rufa'. It can grow 6' to 10' tall. 

Fargesia dracocephala 'Rufa' in my garden, just surpassing 6' after 4 years. The dwarf form should max out around this size.


Back to the plant known as 'Rufa' 'Dwarf', aka Yushania confusa, it would correctly be known as a form of Fargesia dracocephala. Since the International Code of Nomenclature for Cultivated Plants prohibits cultivar names which are purely descriptive (such as 'Dwarf', or 'Blue', or anything similarly vague that could cause confusion). Given this, the most correct name for this plant currently would be Fargesia dracocephala (dwarf form), or some similar descriptive name, at least until it's given an acceptable cultivar name. 

While not a common plant, I hope this post will help those few looking for information about "Yushania confusa" and save them the trouble of the detective work I went through. 

Comments

  1. I can understand why these classification errors happen but they are frustrating, especially among gardeners less well equipped than you are to delve into the specs.

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    1. Bamboos are among the more notorious groups for confused identities, though I'm not sure just how this particular misnomer came about.

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  2. Interesting mystery story--love mysteries--great that you managed to finally tease out a correct ID. It's a pretty plant.

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    1. Thanks for reading after I've been gone so long!

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  3. You are a plant detective! You can go by Evan 'Sherlock' Bean.
    Assuming your findings about this bamboo are correct, it would preform similarly to the Fargesia dracocephala already in your garden, right?
    From reading your previous bamboo posts I know you aren't afraid of bamboo; will you take precaution just in case it turns out to be a runner?

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    1. No, I'm really not worried that it could be a runner. While the name it's being sold under is incorrect, the growth habit of the plant is well-known. The two nurseries selling it are using the name they originally received the plant under, and unfortunately aren't into bamboos enough to notice the name is wrong, but they have grown the plant long enough to know how it grows, and I have the word of an experienced bamboo grower and past president of the American Bamboo Society to back it up. And it's definitely not any of the temperate running bamboos.

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