Walter,
From your reply, I would assume that you have experienced this type of die back problem with your trees. Do you feel that Hokkiado elm are genetically disposed to this type of die back or that it is an environmental issue causing it?
Attila,
I have pondered the same thing myself. It is my understanding that the Hokkiado elm was indigenous to Japan's northern island of Hokkiado. That's why I do not feel it is an issue of "too cold" during our short winters.
The photos posted by B-nut proves that someone in southern California knows how to grow them, at least in nursery containers.
So, based on the feedback, growers in California, Florida, and Germany are experincing similar dieback problems with these variety of elms.
What does this tell us? Is this an indication that these types of elms are pre-disposed to the die back, or that there may be a common environmental (weather, temperature, ect.) issue that promotes the die back, or that there may be a common cultural (how the trees are being grown) issue.
B-nut,
I did not intend to hijack your thread. The photo you posted just peeked my interest and this dieback issue has baffled me for years.
Regards to all,
Paul