The saguaro cactus is easily recognizable for its branches that reach into the sky like arms. Found almost exclusively in Mexico and the southwestern United States, this giant species of cactus can grow to more than 60 feet in the sky. The word “saguaro” is specifically Mexican Spanish, as it originated in the now-extinct Ópata language, spoken by Indigenous people of the Sonoran desert. The scientific name of the saguaro is Carnegiea gigantea, in the family Cactaceae, with “Carnegiea” in honor of industrialist Andrew Carnegie, whose Carnegie Institution established the Desert Botanical Laboratory in Tucson, Arizona, in 1903.