This crested San Pedro cactus is a very rare cactus. Normally would be shaped like a column. But crested cacti have a genetic mutation that causes a ripply fan-shaped pattern of growth. This is a San Pedro Cactus Crest. Crested and monstrose cacti are extremely popular among rare cactus collectors. Aside from the general rarity, crested cacti offer you much more variety. You can have many specimens of the same type of crested cactus, and they can all be different. These are especially valuable because they are growing on their own roots.