Kostas

Its unfortunate they are vulverable to so many things.

I think the rot issue exist for you because they are grown in warm locations where they dont grow naturally.Our Chestnut forests are located in the coldest and wettest of our mountains. Soil is saturated all winter and possibly most of the year(they are on mountainsides though so there is decent drainage although the soil is heavy and saturated) but its cool most of the year as well. The trees are abandoned and they live just fine here!

I think planting exotics doesnt present a problem as long as you get healthy plants and they dont belong to a genus native to your country. There do are some exotics that are invasive and destructive to the local forests and may present problems and these are better not planted.
Exotics arent natural to an area outside their environment(but do are natural as species and do exist wild in their home environment!) but add beauty to the scenery and makes you feel you are in the place you are imitating! Many are pretty rare as well and some outright endangered and benefit from being cultivated and propagated for more people to enjoy and ultimately,for repatriation if possible.

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