What is the importance of Tank Billups’ property in the novel, All the Sinners Bleed?

Tank Billups’ property is a key setting in the novel, which includes a prominent weeping willow. In a raid on Jeff Spearman’s home, Titus and his deputies discover a large painting of the tree titled The Secret Garden. Titus recognizes the willow, having hunted on Billups’ property. The department eventually uncovers numerous bodies in the ground around the weeping willow. In this way, Cosby connects the weeping willow to the darkness and violence of Spearman and the Last Wolf.