The Tropical Fruit Forum

No, never been there. Never been to the US either.Why?
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Our professional base ball tea, The Cincinnati reds, referred to them as being in Zinzinnati.  Our city is of German heritage and misspelling it with Z's is supposed to give it a German twist.  With your name of Zitrus.... I though you may be from Cincinnati.
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In June I will visit the US and Canada for the first time in my life.

I would say it does not as its variebility indicates. But cross pollination is probably not that high in the wild because most citrus types cannot survive where C. ichangensis growth.

The stability of wild species is sometimes somewhat miraculous. We have in my area many wild cherry trees (Prunus avium) and also many cultivated cerry trees (also Prunus avium). They definitely hybridize with each other and you find many intermediate forms. Yet the wild form clearly dominates in forests. Why? Probably because the birds prefer it because its fruits are smaller and better to eat for them. And a second reason may be that the wild form does not vast its energy for big fruits so that it performs better in competition with other trees or in poor soil.

I do not know what it exactly is that give stability to wild C. ichangensis as a species. There may be some factors. But it seems also to be true that "stability" is relative. Therefore the variation within the species.

I think Ilya could shed some light on that.

What's wrong with swingle or Dunstan? Dunstan is probably the most edible of the cold hardy citrus. I'm more interested in hlb tolerance though. Swingle has really good cold tolerance and almost edible fruit.

I would not state that Swingle had edible fruits. Dunstan is slightly better but still not edible. The best citrumelo seems to be stock number 82 at Reto Eisenhut's vivaio in Switzerland. I did not have fruit yet but everybody who could compare says so. Trifolis is also quite nice but seems to be F2 and is probably less hardy than F1 Citrumelo. But in fact Swingle is not that hardy. 5* ist much better.

This one seems promising. It's cold hardy.

https://www.oscartintori.it/en/prodotto/otaheite-orange/

whatever "cold hardy" means. Some sources say Cara Cara was the most cold hardy orange. Blood orange"Montagne corse" is also said to be "frost hardy". The limit seems to be -10°.

Xie shan is still going strong in 7A

But you keep it in a cold frame, do you?

There was a long discussion about the taste of Yuzu in Citrus Growers forum: https://citrusgrowersv2.proboards.com/thread/196/yuzu-taste. Most Europeans valued Yuzu very much while Americans were mostly not positively impressed. The reason seems to be that the Yuzu varieties in Europe are not the same as in the States.

I think there is much difference between old world culinary tradition as well as openness to new taste and preferences in the US. Yuzu-rind is not bitter at all 

Nice table! Data of Poncirus certainly depends on the cultivar. Poncirus can have 100% zygotic seeds or hardly 1%.

Never heard of 100% zygotic Poncirus

I think there are some members which have experiences with coldhardy citrus, but to receive answers you should ask more detailed what you are interested in. I e.g. I have a Yuzu since 3 winters in ground, froze to earth in winter after a low of - 15° C and has now recovered again or a Dunstan citrumelo seedlings two year old in ground took -13° C this winter - all survived, some with slight damages, others with none, depending on genetics and microclimate of place.
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one thing I personally observed was, that C. ichangensis showed much more hardiness on its own roots than grafted on Poncirus. In direct comparison all grafted specimen died from cracks and all seedlings on its own roots survived with leaveloss. under exactly the same conditions. I will test yuzu on its own roots in future.
Roberto

Ilya sent me some Poncirus+ seeds two years ago. There was some variation in the seedlings. And I would say there were also tetraploid seedlings. It is difficult though to count the exact number of zygotic seedlings. Most look too similar. They can be zygotic or not.

Batumi Citrumelo has zygotic seeds at least some at least when the right pollen is used. Batumi Citrumelo has a very good taste. But it is sour.

your batumi CM comes from ADAVO?

I have Kabosu from the budwood that I got from Roberto. The leaves are less round and have some suspicious wrinkles.

Ilya, can you remember, when did I send you this budwood? I think it came from a plant I have lost in the meantime. Originally from a Citrus-friend from Germany. Most likely it is not from Adavo (but I do nor know his source)

No poncirus but a hybrid.

Your yuzu is on its own roots or grafted?

Hmmm .... really "in some kind of english" :-) :-) :-) :-)  The automatic translation is totally insane.

All are grafted plants.

I do not know. Perhaps full dormancy of plants without interruption. From the beginning of November until the middle of February, the garden is completely sunless. In this period, the sun's rays will not reach even a minute over the surrounding houses.

Occasionally, the flowers look like roses. The appearance of the USA119 is very irregular.

I am with you: wintersun is a killer. If there is no full sun protection you can forget all stories about hardyness. One of my yuzus was killed by morning sun. Lowest was -6 or -7°C!! The one in the shade is not damaged at all and Hanayuzu which was hit by evening sun has some cracks but will survive (hopefully)