Young elms grow to about 20 feet here frequently before getting hit with the disease. It kills them very quickly, usually within the same summer of getting infected. It is spread by a beetle that has a very limited flight distance. Trees that are isolated can grow to maturity because the beetle doesn't reach them.
The problem is, those trees seed a lot. The seeds are carried away and eventually grow into a line of young trees that lead back to the mature tree. Then when the young tree line gets infected, the disease can travel back to the mature tree, following the path of the seed spread.
I see many young elms here in southern Vermont, often lining roadsides like a hedge, and then they die out. Also along streams, when the seeds are carried down and sprout along or near the banks. I know of some beautiful mature trees, as tall as 60 or more feet. I saw one quite old one isolated in the middle of town, watched t for years, until this summer I saw one limb die, and I knew it had been infected. By fall, many of the limbs had died, and I wouldn't be surprised if it didn't come back next spring.
To find elms in the northeast, good places to look are hedgerows along stone walls, near streams, and along roads.