Came across this one in a garden centre near me. I've never heard of it. They also have Cascade Gold which looks slightly different, so that counted out my initial suspicion it was a miss labelling. It's got lovely leaf shape and currently some amazing colours in full sun. I wonder how tough it would be compared to Cascade Gold. It's a little steep for me at the moment, at £85. I'm pretty tempted though! Has anyone come across this before or know much about it? I can't see any posts for it in the photo forum, although it appears to be available from the usual online sellers.
Cascade Citrine was released by van Son & Koot a couple years ago along with Cascade Ruby, Cascade Gold, Cascade Emerald. They are a hybrid created by crossing the "Ryusen" variety. I believe Citrine is slightly less golden with slender lobes than Cascade Gold.
Do you have a reference that talks about them being hybridized from Ryusen? (Actually the cultivar is named Ryūsei, meaning Shooting Star). Would be very interested in a link if you have one. TIA -E
@emery I believe that 'Ryusen' is the original cultivar name and the other spelling is a mistake that gained traction due to being used in Yano's book? Link to plant patent for Acer palmatum 'Ryusen' It seems self evident that 'Ryusen' was involved in the breeding/development of these new cascading types but I agree it would be nice to have a reference.
Here's what I know. Ryūsei is a Japanese origin maple, apparently selected in 2000 but apparently introduced from 2003. The Hiragana (phonetic spelling) is りゆゅうせい, but the all-important Kanji spelling, which tells us what maple it is, is 流星, 'Ryūsei', which means "Meteor or Shooting Star". Yano's entry os certainly not an error, as it is verified multiple times in the literature, including twice by Nakajima. Yano states it comes from Saitama Prefecture. He writes MILLENIUM GREEN, which is the usual way of saying this is the trademark or PP name, but no such maple appears in the trade. Now, in 2006 a patent was deposed in the US for a maple called 'Ryūsen', first published in Japan in 2001. This maple has a slightly different pronunciation, ゆゅゆうせん in Hiragana, but importantly it is given a new name: 竜泉, which means "Fountain of the Dragon", a traditional compound word used for fountains (or springs) with a historical or traditional association with a dragon. This maple comes from Saitama as well. Neither name should be divided or hyphenated. To do so is a simple grammatical error. They are single compound nouns. Because of the very similar (if not identical) morphology and source, there is every reason to believe these are the same maple, and the second name was given to 竜泉 was given, after the selection of 流星, but critically _before_ it being published. in order to apply for the PP. Japanese naming rules prefer the more recently published name, rather than the older name, contrary to Western rules. In this case, that was 流星, Ryūsei. Therefore both Yano and Nakajima use this name, and if it is indeed the same maple, Ryūsen is a synonym. This also points up the complication of reading a rōmaji and assuming it means the one meaning you know. "Ryū" means "dragon" when the kanji is 竜, but not otherwise. Further, it is an on'yomi, or Chinese reading, where it might be romanized as ryū or ryō. The kun'yomi, native Japanese reading, is primarily "tatsu." HTH helps and doesn't add to the confusion!
The way I understand it, Kobayashi Maple Nursery, who discovered and introduced the plant, named it Ryusen. It doesn't make sense that a later published name would take preference. I have no horse in this race, don't really care what it is called, but it seems illogical that the original name is changed by third parties and everyone accepts this. See this post from 2007 that seems authentic:
Interesting. I'm not partial to one over the other either, just trying to get it correct according to the rules. I'm a little up in the air on it, this is interesting, but also here-say. Kobayashi was certainly the distributor, but there are a couple of red flags, too. The translation is simply incorrect. Very incorrect. While Yano's book contains many non-standard rōmaji, as you might expect, it is certainly not filled with errors. I cross-reference every entry, I may have Found one entry where Yano and Nakajima (and Yokoi) don't agree . However, according to Japanese sources and dictionaries, it is worth noting that there are many translation errors in Vertrees/Gregory, usually by making an assumption about the rōmaji without looking at the kanji. Yes, there is no doubt there is a Ryūsen that was patented. The question is, if it's the same, which name has priority. Because it is a sad fact that many names do get modified for purposes of a patent. Not saying that happened, but it's not impossible. Naming priority is determined by order of publishing, or ubiquity. Assuming these two are the same, the latter doesn't apply to these two, as both names are present. An example of the ubiquity rule is Koman-nishiki: published later as Shimon-nishiki, and others, but almost always seen under the 1882 name. In the West, we determine precedence by using first published name. But this is not true in Japan, whether we think it makes sense to us or no. The key word is "published", as in a catalogue. This is naturally the rule that Peter Gregory used with the Checklist 1st ed., and were we to change it, many synonyms would change, basically it would be a nightmare. Further, he made the decision, which we continue, to give precedence to Japanese Sources over Western Sources, when it comes to maples that actually originate in Japan. What we believe there is that Ryūsei was selected in 2000 and introduced in 2003, the name is in use in Japan, and that gives it priority. So I can't change the synonomy, regardless of a US PP. -E
"Flowing Spring", the literal translation of 流泉 means much the same as "Cascade" which would make perfect sense for this type of maple. I don't see how "Meteor" (流星) would be relevant or appropriate. Also, google search for 流泉 brings up results from japanese nurseries that show a plant that looks like Ryusen. Likewise an image search for the same brings up loads of hits. So it seems to be on the market in Japan with the name written as 流泉. This name is also in use in Japan, maybe more than the other? I would like to know what name the Kobayashi nursery call it as they selected it and developed it. Presumably it was a seedling from Jiro shidare which was previously found by the father, Jiro Kobayashi. Here is a picture of what is likely the original Ryusen/Ryusei plant at Kobayashi nursery looking quite a mature specimen in the year 2006. It looks older than a plant that was only selected in 2000: Picture credit https://jcra.ncsu.edu/resources/photographs/details.php?serial=585219 (JC Raulston Arboretum)
You understand, whether you, I or the lamp-post thinks the name fits the morphology is completely immaterial. But personally, 流星, Meteor or Shooting Star, seems appropriate enough to me for a weeping cultivar. There are two names of Ryūsen, pronounced the same: 流泉, Flowing Spring, is an earlier name for 竜泉, Ryūsen, Dragon's Spring. The kana (pronunciation) is the same. 里枝垂, Sato-shidare, is another name for the same maple (according to Nakajima but not Yano). Anyway, I just try and apply the rules. Back to the subject of whether there is any hybridization from Ryūsen/Ryūsei, weeping maples (shidare) aren't that rare, and as anyone who grows seeds from the afore-mentioned knows, they do throw a lot of weeping forms. Hand pollination doesn't seem like it would be Van Son & Koot's thing, as they're more involved in large scale industrial production. So it seems most likely to me that they grew several thousand ryūsei/rysen seedlings, and selected from them. -E
