I am sorry for this delayed reply to your gardening question. The spring rush has brought a deluge of questions and we are working hard to catch up!
That is a tough question you asked. Here are some web sites for you that list plants that will grow under a black walnut as well as those that won't. Keep in mind that not all plants listed are going to be adapted to your area.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
Q&A Library Searching Tips