This is a dramatic cool growing Mexican species. Previously identified  as Oncidium tigrinum.

As you can see from the photo above the species produces very long branched spikes(this one is 2.5m long)with large flowers spread quite sparsely. The delicious sulfur yellow lip is really striking even when it is high above you in the roof of the greenhouse.The species is found from 1600 to 2500m in cool oak forests which experience much wetter summers than winters but we find plants don’t appreciate dying out to much in the winter although good drainage in a basket seems to suit them best. We grow the species in a basket in cool Americas.

The spikes are pretty much self supporting and we like to let them arch naturally.