Sorry, cannot solve your mystery. Den. compactum is a species orchid from South East Asia that was at one stage recorded as the parent of some hybrids in the RHS Site. but i always wondered if there hadn't been a mix up with Den. bigibbum var. compactum.
Have no idea at all about the Udom Blue-Blue bit.

Udom appears to be a grower/breeder in Thailand.

I found references to an orchid called:

Den. compactum var gouldii x Den. Udom Blue Angel

which is close, but not a match. Udom Blue Angel is registered, and appears to have been used as a parent several times. Perhaps the name has been shortened on the tag to "Udom Blue" and the clone name is 'Blue'?

I am very far from a dendrobium naming expert, so unless arthurm on this board has an answer, this is probably at a deadend. compactum var gouldii makes no sense to me, as i thought compactum was a var of bigibbum and gouldii was its own species!

Thanks for the replies.

tee530 did you happen to find a picture of that cross? If I could see it I could compare it to my current blooms. Looks like that one would be a good bet. At least if there is a mistake in how it is identified it seems to be the same mistake. It's a shame it is not registered itself, it is a nice plant that has bloomed well for me.

It is confusing the way the Genera, species and variety names are changed. I was trying to find out who the parents of my Lc. Mini Purple are, and that's a plant I see in a lot of crosses, so I was very surprised when I could not find it. It took me a while to relize it was the Mini Purple listed under Sophrocattleya. Not Fair!! It was probably an old change and I am behind the times but, couldn't they list the old names that are on everyone's tags and refer those to the new ones? That way we slow-pokes can keep up.

There are a whole host of changes on the way that will just cause confusion in the orchid growing community. I didn't know that Laelia pumila had become Sophronitis pumila.

There is no way that orchid nurseries are going to record old and new Genera and species names. Some nurseries are still selling Colmanara Wildcat ages after it became Odontocidium Wildcat.

The only reason i know a little bit about the names is that i record the results from orchid shows and meetings for a local OS.

Meg -

The link to the cross I referenced was dead, but if you want to check it later, you can find it by googling "dendrobium udom" and looking about halfway down the first page. I tried putting the link into the message, but GW rejected it as a spam site!

I did a google image search and found a picture of Dend Compacttum Gouldi x udom Blue at:
http://images.google.com/imgres?imgurl=http://thumb10.webshots.net/t/14/14/9/80/11/224698011OKCDUS_th.jpg&imgrefurl=http://www.webshots.com/search%3Fnew%3D1%26source%3Dtop_mh%26query%3Dmember%253A%2Bgolfmobile&h=75&w=100&sz=3&hl=en&start=1&tbnid=VhwcwOq9KPKLkM:&tbnh=62&tbnw=82&prev=/images%3Fq%3DD.%2B%2BUDOM%2BBLUE-BLUE%26gbv%3D2%26svnum%3D10%26hl%3Den%26sa%3DG

It's in the eighth row of photos on the page.

Marci in Chicago

Thanks chi town. I would not have found that on my own. The thumbnail that Google brings up is not even close! So I wouldn't have gone past that without your note. That pic is definitely a good match.

tee530, I found that link and tried it. It worked! His plant is larger than mine but everything else matches.

I have only 10 blooms right now but, that is on a secondary spike on a cane which flowered earlier. This yearÂs growth has yet to bloom and a new cane is just starting. If I can keep the plant healthy maybe I'll get multiple spikes as well.

Arthur, I know it would be too much for each grower or nursery to keep up with all the changes but, since The RHS is responsible for registering all of the names wouldn't it make sense to have a traceable chain of changes. They must do that somewhere even if it is not available on their site. It must be a real challenge for your record keeping.

Thanks for the help.