This is one of the famous rootstock in the Philippines. It is a hybrid between Kalamansi and a mandarin. For us here, that means a hybrid between Calamondin and probably a Ponkan type mandarin.

Has anyone have it here in the US? How did it perform?

Joe,
There are several large Calamondin/mandarin hybrids in Aiken, SC, where we will have our citrus expo in November. I am sure Bob McCartney got the seed from the Citrus Arboretum at Lake Alfred. The fruit is not that great, but I have wondered how it would work as a rootstock. Calamondin does fine here on its own roots. There are several 25' seedlings near my nursery.

I have a couple of rooted cutting from the trees in Aiken.

Ned

I would guess it would be close in performance to Cleopatra mandarin, and probably with the same dwarfing effect and fruit quality.

That's just a guess as to how the rootstock would perform. It would be also susceptible to phytophtora.

With regards to fruit, that is to be expected, that is why it is only used as rootstock in the Philippines. It will now lack the zest of Calamondin, and the rind would be more unpalatable.