Pachycereus pecten-aboriginum is a columnar cactus plant native to Mexico. They can grow up to 15 m high. The trunk of this species is 1.2 to 5.0 m tall. The specific name, pecten-aboriginum, is from the Latin, and means "native combs".
The cactus has a broad distribution along the Pacific coast of Northwestern México. It is one of the most massive columnar, treelike cacti in the world, often 7 to 15 m tall. The trunk is short but very large often branching within 0,5-3 m of the base with many massive branches. Pachycereus pecten-aboriginum blooms with white with reddish brown exterior, showy with purplish outer petals flowers that are 5 to 10 cm long, with a floral tube covered with dense brown velvety wool. Unlike other columnar cacti it may flower at any time, even though late winter and spring is the most common. The flowers are nocturnal, open in the evening and closing about midday.