The Easter Big Freeze Disaster of 2007 killed off almost every one of my grafted heartnuts/buartnuts/Carpathian walnuts, and many of the seedling butternuts & Japanese walnuts.
I’ve got a seedling of Bountiful(which was misidentified and sold for decades as a butternut until genetic testing revealed it to be a buartnut), germinated in 1998, that has yet to produce a catkin, much less a nut. Seedling butternuts, from seednuts sent by an acquaintance from north GA, have been bearing for a few years - but I’ve either planted or given away every nut they made. I’m hoping that when the Bountiful seedling finally begins to bloom & bear, that it, the seedling butternuts, and the sole remaining heartnut (Late Rhodes) will be compatible with one another.