Oreocereus
Oreocereus
Morphological Summary
Genus of Andean columnar cacti, known as "old men of the mountain" or "woolly Andean cacti". Characterized by columnar stems covered with DENSE WHITE OR COLORED WOOL and long bristles, giving them the appearance of being covered in hair or snow. Red or pink tubular diurnal flowers, hummingbird-pollinated. Endemic to the Andes of Peru, Bolivia, Chile, and Argentina, at altitudes of 3000–4500 m. The name combines "oreo" (from oros = mountain in Greek) + "cereus" (columnar). The wool acts as thermal insulation and protection against high-altitude UV radiation. Very popular in cactus collections for their striking woolly appearance.
Oreocereus celsianus f. cristata
Crested Old Man of the Andes
Oreocereus celsianus 'Fossulatus'
Old Man of the Andes cultivar Fossulatus
Oreocereus celsianus (Lem. ex Salm-Dyck) Riccob.
Oreocereus doelzianus
Doelz's old man cactus
Oreocereus doelzianus (Backeb.) Akers
Oreocereus fossulatus
Grooved Andean old man cactus
Oreocereus hempelianus
Hempel's old man cactus
Oreocereus hempelianus (Gürke) D.R.Hunt
Oreocereus lanatus (Kunth) D.R.Hunt
Oreocereus leucotrichus
White-haired old man cactus
Oreocereus leucotrichus (Phil.) Wagenaar Hummelinck
Oreocereus piscoensis Rauh & Backeb.
Oreocereus pseudofossulatus
False grooved old man cactus
Oreocereus pseudofossulatus D.R.Hunt
Oreocereus rettigii (Quehl) Hutchison
Oreocereus ritteri
Ritter's old man cactus
Oreocereus tacnaensis
Tacna old man cactus
Oreocereus trollii f. cristata
Crested Old Man of the Mountains
Oreocereus trollii (Kupper) Backeb.
Oreocereus variicolor
Many-colored old man cactus
Oreocereus variicolor Backeb.
Oreocereus websterianus
Webster's old man cactus