A long time ago american chestnut trees were plentiful- found in america from maine to flordia. then a blight or fungus came along brought over on chinese chestnuts. of which the native american chestnut had no defence practiclly. Killing four billion trees in around 60 years tops. Some of theses chestnuts were 150 feet tall and 13 to 10 feet wide at the base.
I recently found out that The american chestnut foundation is crossing chineases and american trees which have shown resistance to the blight. and then back crossing those trees to american size and growth habit but with chinese resistance, they in tern produce nuts that are possibly able to survive blight. Now I dont live in chestnut county, i'm in zone 4 mn, but for those that do... it would be a cool thing to be part of. .
I urge you if you can to become a member if you live in those areas and try to find public land- state parks- nature resurves that are willing to try to plant the seedlings grown from the possibly blight resistant nuts. The membership is at its cheapest to get nuts is $300 but you get other benefits too of which I dont know