The walnut of the North Carolina Cannonball Walnut Tree can weigh as much as one pound in documented cases. These walnuts are four times larger than the Thomas Black Walnut, and the plump, delicious kernels when cracked shell out much easier in comparison. The nuts of the North Carolina Cannonball walnut are the largest Black walnuts that have ever seen. The North Carolina Cannonball Walnut Tree has many uses, and its delicious kernels are tasty, oily and crunchy. The leaves of the North Carolina Cannonball Walnut tree turn bright yellow after a frost, and the tree itself is an excellent shade tree.