While common in Mexico, the organ pipe's presence in the United States is only here at the park. The organ pipe's limbs have a look similar to the saguaro but there is a fascinating difference. Its arms all grow out of the base of the plant while the saguaro's arms grow high off the main stem and only after the plant has lived for many years. The main difference is that the senita has only four flutes on it arms while the organ pipe has many. The desert environment is very fragile.
Slight changes alter the vegetation.
Cacti tend to cluster in micro-environments which suit them best. Shown left, the teddy bear chollas are clustered on the lower hillside while the organ pipes are near the top of the hill where it's steeper. Saguaros tend to favor bajadas, large plains which are gernally flat but mildly sloping. Amazing forests of saguaros can be found at Saguaro National Park just outside of Tucson, a 90 minute drive from here. Visitors to the area should also check out the the Arizona-Sonora Desert Museum, one of America's top museums.