It's farreri, after Reginald Farrer.

And it's now Cupressus vietnamensis. Anyone know of the coldest place C.vietnamensis has been trialed? Seems like zone 7 was the answer last time I had asked.

Dax

Too soon for any testing to have produced significant results, unless lower than normal temperatures were involved.

Otherwise, when a planting of it survives without dieback or distortion due to frost for decades in a location, then we can start to talk about a tree being hardy in that climate.