Hi Millet. For mandarins I think my Ponkan is about the most upright tree I have. The Pong Koa is doing great, I planted it out next to the deck. I has about 30 small fruitlets on it. I'll try to get a photo tomorrow.
If your BC2 is big enough to take some budwood from I would be greatful
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. Bonnie does not have this variety anymore.