I suppose I should probably conclude all this desert talk by mentioning the supreme being in Organ Pipe National Monument, the park's namesake, the organ pipe cactus (Stenocereus thurberi). The organ pipe is a species of cactus native to Mexico and the southwestern United States and is much rarer in the U.S., with the exception being, of course, Organ Pipes National Monument, where a major bulk of the American organ pipes live. The organ pipe has several narrow stems that grow up to the sky from a short trunk that peaks above ground level. The plant originated in the warm, dry tropics, and when the global climate warmed at the end of the last Ice Age, the cactus slowly began migrating further north. It arrived in the Sonoran Desert only about 3500 years ago.It takes 150 years for the cactus reach maturity, and at around 35 years old, it begins to produce white flowers that are open at night and closed by the morning. The species is predominately found on rocky hillsides up to 3000 feet in elevation, as it is sensitive to frost and is rare in low desert areas. She's quite a lady.