The 'European Boxwood & Topiary Society' may qualify. It has in certain aspects more than the ACS, and less than the ACS in other aspects https://www.ebts.org/

I know that the hibiscus society does. So does the CCCR (an organization started by me to list cultivars which have been chosen, named, and cultivated within the county).

www.cccronline.tk

Interesting...some are superb (Rhododendron and CA Native Plant Societies) and the Rose Society can get away with making it members only. Most of the rest are hard to use or largely unpopulated (such as the Hibiscus Society). Thanks for your responses.

The American Rhododendron Society has two, one for rhododendrons and one for azaleas, even though both are botanically Rhododendrons.

Most of the rest are hard to use or largely unpopulated

Yes, I haven't noticed that many useful offerings in the past myself (not that I have done a survey). Really the Conifer Society one is the only database style file I have seen on the web and explored there. The Hebe Society also has pictures and descriptions, but as I remember it it is a selection. And it is not in database format.

The Magnolia Society checklist web pages have histories and descriptions in a narrative format - but have not been updated in 17 years (they are working on it). Meanwhile multiple different horticultural selections have been put on the general market by Monrovia and others.

The American Rose Society publishes a printed volume of Modern Roses periodically (that includes all types) but as of the last edition I looked at was still using wrong nomenclature for specific kinds I have long studied. While promoting the book as the standard reference. So even if this source has a file on the web (members only or otherwise) it might not be completely reliable.

This may be a starting point for finding some information sources of interest - as far as correct nomenclature is concerned. I used an ICRA when I registered a conifer I selected.

https://en.wikipedia.org/wiki/International_Cultivar_Registration_Authority

The American Rhododendron Society database of common cultivars has been around longer than the ACS one:

http://www.rhododendron.org/search_intro.asp

however the leader in online plant databases, by far, is the European hirsutum.info for Rhododendrons and Azaleas. It is probably one of the most extensive, but far more importantly is the only one I know about that (logically - the whole point of a real database) allows "drilling down" on dimensions of parentage, or by hybridizer.

Hirsutum.info -- Rhododendron Hybrids/cultivars: 'Nancy Evans'

For example starting with Nancy Evans, you could drill down to the hybrid created between it and a species:

Hirsutum.info -- Rhododendron Hybrids/cultivars: 'Nancy Evans x horaeum'

then see what else that hybridizer has created:

http://www.hirsutum.info/hybridizers/plants-hybridizer.php?hyb=639

Yes I thought that the ARS was one of the best that I looked at. I asked this question because we have extensive traffic on the ACS website (which continues to grow at 25-30%/year) and at least half of it is driven by our database. As we try to decide how to allocate Society resources, I thought I would look around at others. The president of the ARS is also an ACS member so I will compliment him!

Thanks for noting the European site.

"Thanks for nothing the European site."

Huh? Did you mean thanks for noting?

Corrected! Damn spellcheck.

Haha, no problem. But it does make the other sites seem somewhat primitive, so whoever is tasked with improving them might say to her or himself, "thanks for nothing". Of course parentage is obviously less important for conifer cultivars, but it still might be useful to browse the data based on say, who discovered a cultivar.

It's an enormous undertaking, especially for an all-volunteer outfit. Many of our entries are added or updated when members ask questions. The editor of the database works full time and has other obligations and he is scrupulous about the research and nomenclature. And then there is the matter of getting photos, etc. Conifers are particularly difficult because unlike camellias, for example, they are prolific in almost all climatic zones and six of the seven continents, so cultural requirements are all over the map.

Yep, understood on the magnitude of the task. Apparently the persons who coded and filled hirsutum.info with data are taking an indefinite break from the task. Just what I've heard through the ARS grapevine.

Actually the ACS one has more data though, than I remember from looking at it a couple years ago. I like this "article" format, I think it makes more sense for conifers. So on this entry:

http://conifersociety.org/conifers/conifer/metasequoia/glyptostroboides/ogon/

It's pretty darn good as it is, but, again, the ability to click on Larry Stanley and go to a holder page of any other articles mentioning him, would be nice. Any kid who knows programming well should be able to set something like that up in a quick, semi-automated way, just use some perl and regex to convert selected bits of bolded text to a special hyperlink of whatever is bolded. (I don't do web design, per se, but do work in IT and have dealt with web designers for over 15 years)

"A mature specimen will easily exceed 20 feet (7 m) tall after 10 years in the landscape."

Try 5 years LOL.

Yes linking would be nice but it's one more thing to have to maintain. Third parties change or go away, new ones emerge. If only we had a staff...

Yes, I encounter dead links even on rather official sites pretty often.

Yeah it's really common. Urls change all the time. Google is now so sophisticated that it almost is just as easy to do it that way.

After years of Google my computer guy suggested Bing and I liked it. But now I am using Avast Safe Zone and that presents me with Yahoo.

Which doesn't make me Ya-h-o-o-o-o!

(I also use Google Chrome part of the time, because that works best for some work I am involved with).

I use different browsers and different search engines depending on what I'm doing. As long as it's not Internet Explorer, it generally works well. One of the problems with IE is that no software developer uses it him/herself so they are always slow to catch problems with it.

Embothrium, not to get off topic, but you can disable the "safe zone" extension. It is really a bother, that doesn't really secure anything. When on windows I use firefox. Right now I am on a chromebook, so I am obviously using chrome. I agree that internet explorer has problems, and that is why microsoft discontinued it in windows 10. Also, the dead links are annoying. I just went through a rebrand and had to change the domain names. My websites were full of dead links for a week (and probably still have some).

I was talking about the Avast Safe Zone browser. It is a feature of the Avast anti-malware program. Which is not free-ware - I'm not going to buy protection and then turn part of it off.

As it is when I use Chrome I am not in Safe Zone.

With my business protection I disable it because it is a bother. But, your choice.

""A mature specimen will easily exceed 20 feet (7 m) tall after 10 years in the landscape."

Try 5 years LOL."

I did not try it, but the better landscaping software packages these days advertise how-your-landscape-design-will-look-like-over-the-years feature. Wonder where the software designers get their raw data from, it won't be all pure fantasy.