(Phil.) Wagenkn
The genus Oreocereus was first established in 1909 by Vincenzo Riccobono and today encompasses just six species (and a few subspecies) of distinctive plants which grow in the Andean region of Chile and Peru.
Oreocereus leucotrichus was added to this genus in 1956 by Rodolfo Wagenknecht but had been first described as Echinocactus leucotrichus in 1909 by Rudolph Philippi. At other times the species has been described as an Arequipa, a Borzicactus and, more recently, even as an Echinopsis!
Fig. 1 Oreocereus leucotrichus in December 2018
Leucotrichus, which is derived from Greek, means white-hairy, but the additional attractive feature of some clones of this columnar plant is the yellow or orange spination. My largest specimen is 1.2 metres tall and has rewarded me with a flower or two on just two occasions in recent years. The red flower is about 6 cm long and is situated close to the apex of the plant. Having no other Oreocereus to use as a pollen source, I crossed this flower with Cleistocactus strausii. A fruit rapidly developed during the next week and the harvested seed has germinated readily to produce many seedlings. It will take some time to find out if I have some attractive hybrids.
Fig. 2 Oreocereus leucotrichus in flower in 2013
The only other Oreocereus which I have flowered regularly is Oreocereus doelzianus var. sericatus (or Morawetzia sericata, if you prefer!). This differs from other Oreocereus in that it develops an apical cephalium, consisting of dense bristles and hairs, from where the flowers appear. It is a clumping species and will flower when the stems are less than 30cm long.
Tony Roberts
No part of this article may be reproduced without permission. Copyright BCSS & the Author 2019
