Greetings,

So we can best assist, are you asking for backyard production or for commercial purposes?

Sorry for the lack of clarity.  I have an area with a northerly aspect at about 600’ in the Chehalem Mountains where I’d like to grow a commercial crop.  One Green World has a variety, Ichandrin, hardy to 0 F.  Would this be a viable crop in this situation, or should I stick to blueberries? 

I found a paper from Korea stating Yuzu trees grow in a warm climate of between 13–38 °C or 55-100°F annual average temperature, and are more cold tolerant than most other citrus species, being able to withstand daily minimum temperatures down to −9 °C or 15.8°F.

I wasn't able to find research papers on Yuzu production in the US - but garnered that it is possible to grow Yuzu in the Willamette Valley. The trees prefer full sun - so a north facing slope will pose challenges. If you were growing Yuzu for home use, then protecting the plant during the winter with a wrap and covering the ground with mulch.

You could try a couple trees at your site, observe for cold injury or other factors impeding production. If they do well and you're satisfied then increase to a larger area. If you wanted to avoid the risk, then sticking with blueberries would be the way to go.