Cereus and related species are tall, often tree-like cacti, and only three are common in the Southwest: the saguaro (carnegia genus), senita (pachycereus genus) and organ pipe (stenocereus genus). The latter two occur most visibly in Organ Pipe Cactus National Monument in south Arizona but the saguaro is widespread, one of the universally recognized symbols of this region. The only other cereus-like plants in the US are bergerocactus emoryi, along the coast in far southwestern California, and peniocereus greggii in Arizona, New Mexico and Texas. Many more varieties of columnar cacti are found in Mexico, Baja California and South America.