Evaluation of Eucalyptus Globulus for Mixed Tree Plantation with Some Indigenous and Exotic Tree Species in Central Ethiopia Highlands

Mono-crop plantation widely found in the world and dominated by few species such as Eucalyptus, Pinus and Tectona. While they lack diversified product, negative to environmental service and limited forest product for local use. The experiment was designed to evaluate the impact of mixed plantings on the early growth performance of the E. globulus tree species. The treatments included one monoculture of E. globulus and a combination of the plant with three other native and one foreign tree species. In four consecutive years after plantation, height, root collar diameter, DBH and leaf/branch count were measured. Following two years of out planting, the survival rates of seedlings were determined. Destructive sampling was applied to measure biomass of E. globulus. The growth performance of E. globulus in mixed plantations was compared to that of trees produced in pure plantations. The findings showed that there were no significant variations in growth parameters across the treatments. Following two years of out planting, the survival rates of seedlings were determined. The growth performance of E. globulus in mixed plantations was compared to that of trees produced in pure plantations. The findings showed that there were no significant variations in growth parameters across the treatments. The survival rate of E. globulus was good, ranging from 75 to 96.8%. Similarly, the growth performance of E. globulus's root collar diameter was larger even if the trial did not reveal a significant difference between the treatments for height. In comparison to other treatments, the one that included junipers and E. globulus had a higher mean height throughout the course of three years (1.28, 2.53, and 6.12 meters, respectively), as well as a lower RCD in the first and third years (1.3 and 5.34 cm). At year four, E. globulus attain higher in Height and DBH with high growth rate in mixed plantations compared to pure stands. The relative yield of E. globulus in pure stands compare to mixed stands greater than 1. Above and below ground biomass and carbon density of E, globulus is comparable in all treatment. Overall, the study's findings confirm that planting E. globulus improves its mingling with the examined tree species. Such studies ought to be conducted again over a longer time frame in order to examine the effects at a later stage and recommend technologies for broader implementation.