Growing on the edges of the desert are these pale green cacti with long yellow spines. The cactus grows as a single cylindrical body, and when moisture is abundant, the cactus will sprout several white flowers near the top. After the flowers wither and fall off, they leave deep holes in the surface of the cactus. When the desert winds pass over these holes, they resonate at an unusual frequency that creates an eerie sound that can be heard for over a mile. Many nomadic tribes will avoid areas near the cactus, believing the plants to hold the souls of the damned that howl for eternity.