Euphorbia columnaris

Euphorbia columnaris
This is one of more remarkable and rare species and a fine addition to any collection! 
 

Description: This is an slow growing columnar species with its distinctive spines that resemble cactus. It is probably the rarest euphorbia of all.
Stem: Yellow-green unbranched, except when damaged with up to 16 angled rib that can achieve heights of 90 cm or more.
Spines: 2 cow-horn shaped, greyish to chalky-white that line the ribs.
Flowers: In clusters of up to 30 small fine yellow cyathia.

Cultivation: Difficult to grow on its own roots it is almost always grafted on either Euphorbia fruticosa or E. canariensis. But it is that as it may be degrafted and rootted. It like a sunny position. It does best in a mineral soil, good drainage is essential. Water sparingly during the summer months and keep dry in winter. It is a slow growing long lived plant and once established, it will be content in its position and with its soil for years. It can tolerate moderate shade, and a plant that has been growing in shade should be slowly hardened off before placing it in full sun as the plant will be severely scorched if moved too suddenly from shade into sun.

Propagation: The plant can be reproduced by grafting or cuttings (seeds are seldom available).

Scientific name:  Euphorbia columnaris P.R.O.Bally
In: Candollea 19:151. 1964

Origin:  This is a narrow endemic Euphorbia only found in a small part of northeastern Somalia.  Around Las Anod in the wadi Nugaal Region.

Habitat:  It grows on gypsum hills. The vegetation is a open semi-desert grassland or bushland. The area support a rich endemic succulent vegetation (e.g. Aloe inermis, Dorsteinia gipsophyla, Adenia aculeata, Rapanocarpus stefaninii, pterodiscus and carralluma spp.) This species is virtually extinct in its habitat.

Conservation status: Listed in CITES appendix 2.