Bought about 7 years ago and is still going. It's about 5 foot+ tall, and produces lots of bulbils down the stems.

'Yellow Bruse'?

Yes, 'Yellow Bruse'.

JGormley67: On the Garden.org plant database listing for Yellow Bruse, it doesn't mention bulbils as a method of propagation but your suggestion is the nearest I've seen so far. On a Google picture search, one supplier in the UK (hwhyde.co.uk) has an almost identical photo as mine, although it's not currenty listed. Here is Hyde's photo.

The Lily Register's Sixth Supplement shows 'Yellow Bruse' being registered by a Dutch bulb company in 2014, so the timing would be consistent with you getting this about 7 years ago. It says the hybridizer was Robert Griesbach and that the parentage is unknown. No mention of bulbils in the description, but it is very likely that L. lancifolium var. flaviflorum is in its background, as this is a vigorous stem bulbil producer.

Thanks to all of you for your suggestion and research. I do like to put names to plants rather than to label them as unidentified!

I am wondering if this might be tetraploid seeing as it is from Griesbach. Has anyone played around with it?

I had bulbils on some of my plants (when I had them) so they produce bulbils sometimes.

I am quite sure it is a tetra - breeds well with tetras.

I too would assume it is a tetraploid as I have set seed on it using tetraploid pollen.

@mike_jw
I have a couple Yellow Bruse in the garden currently. I'll let ya know if I spot any stem bulbils. They are just starting to open today, so it will be a bit before I know anything about stem bulbils.
Cheers
AkLily

I did use it with a tet yellow black spotty 1b.Came out identical to Yellow Bruce