Thanks for the question. What do you mean by "99% American"? Do you mean that the trees look like American chestnut trees, for all intents and purposes, despite having Chinese chestnut ancestry in them? Or do you mean that they are genetically > 99% American chestnut (which would require knowing that the only Chinese chestnut heritage was 7+ generations ago).
If these are a named cultivar and we don't have it in the database, please feel free to propose an addition (you'll need to find an online reference, though).
Otherwise, the best spot for your photos is the genus entry (which I've just created, since we apparently didn't have one previously!): Chestnut (Castanea)