Durability of Ethiopian bamboo culms and alternative damage control measures against biodeteriorating agents

Abstract

High susceptibility of the bamboo stems (culms) to biodeteriorating agents are among the major challenges in processing, value addition, marketing and rational utilization of the bamboo resource in Ethiopia. A study was conducted to  investigate culms’ natural durability, treatability of bamboo culms with and effectiveness of damage control measures in controlling the biodeteriorating agents’ damage. Samples of Arundinaria alpina culms were collected from Hagere Selam, Injibara, Tikur Inchini and Masha sites. Oxytenanthera abyssinica samples were obtained from Asossa, Dedessa and Pawe. Tanalith preservative, borax-boric acid solution, used motor oil, kerosene and common table salt were used to treat the bamboo stakes. Graveyard studies were conducted for five years at Pawe, Bako, Adami Tulu and Addis Ababa research stations. The non-ground contact test was conducted in Addis Ababa station under shade without direct contact with soil, moisture, rain and sunlight. The results indicated that bamboo culms were non-durable, having high treatability potential with the control measures used in this study. Significant difference (P<0.01) was found on damage caused by subterranean termites on the bamboo species stakes obtained from different localities, control measures and field (graveyard) stations. Mean damage on controls and treated stakes with control measures caused by subterranean termites for all stations varied from 24 to 80%, while damage caused by fungi varied from 11 to 66%. This indicated that termites caused the highest damage at all stations both on the controls and treated stakes. The non-ground contact stakes were intact against aboveground dwelling termites, beetles and fungi. Tanalith and used motor oil treatments were found to be the most effective alternative control measures in resisting biodegrading agents attack and prolonged bamboo culms service life to more than five times compared with controls.

Keywords: Arundinaria alpina, Control measures, Culms, Graveyard stations, Oxytenanthera abyssinica, Stakes