Adaptation and Growth Performance Evaluation of Agroforestry Tree Species under Dire Dawa Administration and Harari People Regional State Condition, Eastern Ethiopia

Abstract

Tree growth is a function of the genetic potential of the species and environmental conditions. Hence, before introducing any species to a given agro ecology there is always a need for a well conducted field trial for matching species to a particular site. A study was conducted to evaluate adaptation and growth performance of five agro forestry tree species at Dire Dawa Administration; Adada2  and Harari Region; Erer dodota for three years ( June 2016-June 2019). Five agroforestry tree species (Sesbania sesban, Moringa oliefera, Gravilea robusta, Azadarichta indica and Leuceana leucocephala) were compared in randomized complete block design with three replications. Data on growth parameters, diameter, plant height and survival rate were measured and recorded at interval of three months. Results revealed that there were highly significant (p<0.05) variations among tree species in height growth, root collar diameter development, diameter at breast height and survival rate at both study areas. This could be due to environmental factor and/or genetic potential of the species, which generally govern the growth of a given species. Among the species tasted, Moringa oliefera showed the highest performance followed by Azadarichta indica, Sesbania  sesban and Leuceana leucocephala in terms of height growth, root collar diameter and diameter at breast height at both Dire Dawa Administration ad Harari Region. After three years of establishment, Moringa oliefera, Azadarichta indica, Sesbania sesban and Leuceana leucocephala showed the highest mean survival rate at both study areas. Hence it can be inferred that the conditions of Dire Dawa Administration and Harari Region matched with the environmental requirement of those tree species. On the other hand, species of Gravilea robusta showed lowest performance at both study areas. Thus, the long dry season, which extended from eight to ten months in the study area,  clearly explains  the  poor  survival  and  growth  response  in  some  of  the  species. Generally, these  findings  may  help  forest and agroforestry managers to  properly allocate  species  into  the  site  that  grow  and  adapt  well. Further testing of provenances of the best performing species is recommended to select the most adaptable ones for such areas for future agroforestry practices at wider scale; on which success of agroforestry practices and forest plantations depend.

Keywords: Agroforestry, diameter at breast height, height growth, root collar diameter

DOI: 10.7176/JEES/14-1-03

Publication date: January 31^st 2024