Can st augustine grass survive in the Bristol TN area?
My yard is surrounded by trees. Very little gets sunlight; in fact, I joke about having to mow my weeds.
St Augustine is not reliably hardy that far north. There are other grass types that could work for you, as well as non-grass groundcovers. This article has more information: https://www.gardeningknowhow.com/lawn-care/lgen/growing-grass-shade.htm
Also, here's an article on grass for your part of the country: https://utextension.tennessee.edu/publications/documents/PB1626.pdf