Parthenium weed (Parthenium hysterophorus L.), an invasive alien species, has been spreading at alarming rate in Ethiopia, causing biodiversity degradation, yield losses in field and horticultural crops, health problems to human beings and livestock. A study on the socioeconomic and ecological impacts of P. hysterophorus was conducted in five Kebeles (lowest administrative division) of Boset Woreda (District), Ethiopia. Data was collected using Ecological Survey, Semi Structured Interviews, Focus Group Discussion, and Field Observations. 200 quadrats were employed where every plant species found in each quadrat were counted, recorded and identified. Data on informant's perception about the first appearance, infestation levels, agents of dispersal, impact, and cultural management of the Parthenium weed were analyzed using descriptive statistics. Shannon Diversity Index (H′), Species Richness, Evenness, and Jaccard's Similarity Index were executed to evaluate Parthenium's effect on species diversity of the weed flora. 78 Herbaceous plants belonging to 59 genera and 21 families were collected. Poaceae (28.2%) and Asteraceae (16.7%) were the dominant families of weeds observed in the study Kebeles. Digalu and Merko Kebeles had high infestation of P. hysterophorus represented by high distribution, abundance, and dominance of the weed, but with corresponding low Richness, H′, and evenness of herbaceous plants. Species Richness of herbaceous flora and abundance of Parthenium weed reveled significant negative association (P < 0.01; R 2 = 0.93). Most of the informants believed that Parthenium affected crop and livestock production as well as human health. Farmers employed hand weeding, plowing, and manual clearing to manage the weed. For effective use of the weed, Integrated Weed Management approaches are required to check the spread and reduce the adverse impacts.

Wabero forest is one of the very few remnant moist evergreen montane forests in Southeast Ethiopia. However, basic data on vegetation structure and composition of the forest that could provide valuable information for possible conservation measures is lacking. The main objective of this study, therefore, was to investigate the woody species composition, vegetation structure and regeneration status of the forest. In the study 30 quadrants of 20 m by 20 m were used for woody species data and 5 m by 5 m for sapling and seedling in a nested form. The sample quadrants were laid down along transects at a distance of 300 m from each other. Diameters at breast height (DBH), basal area, frequency and importance value index were used for analysis of vegetation structure. In the study, a total of 47 woody plant species belonging to 43 genera and 33 families were recorded. The major families were Rubiaceae and Rutaceae each represented by four species followed by Sapindaceae, Moraceae and Oleaceae each represented by three species. The rest of the 28 families were represented by one or two species, only. The mean density of all the woody species recorded in the study site was 21,737 ha -1 . Diospyros abyssinica, Podocarpus falcatus, Strychnos mitis, Celtis africana and Coffea arabica were found to be the most dominant and frequent species with the highest importance value index. Results of regeneration status of the forest, which was analyzed by comparing number of seedling and sapling with mature trees, revealed that the forest is under good regeneration status. Therefore, based on the results of the study, awareness creation and implementation of participatory forest management strategy is recommended in order to sustain the forest.