Population structure, phenology, and fruit yield of Syzygium guineense (Willd.) DC in the dry Afromontane forest of Guangua district, Northwestern Ethiopia

Syzygium guineense is the most important species in the genus Syzygium and the family Myrtaceae. It is a large evergreen flowering plant native to tropical regions. However, the role of S. guineense in developing countries has been neglected and underutilized for many years. The aim of this study was to (i) examine the current abundance and population structure of S. guineense and (ii) determine its phenological characteristics and fruit yield potential of the species. Thirty main sample plots (20 × 20 m) and five subplots (5 × 5 m) were established to record diameter, height, other co-existing woody plant species, and regeneration. Additionally, thirty mature S. guineense trees were selected to study their phenological phases and fruit production. Quantitative data were analyzed by calculating density, frequency, dominance, and importance value index, as well as through analysis of variance and correlation. The results showed that the population structure of S. guineense is an inverted J-shape, with an average of 417 trees per hectare. This includes 333 seedlings and 43 saplings per hectare, indicating fair regeneration. The highest number of individuals was recorded in the smaller diameter and height size classes. Syzygium guineense is a predominant and ecologically significant species compared with other associated species in the study area. Syzygium guineense took approximately 155 days to complete its flowering and fruiting phenophases from the end of January to June and on average produced 29.1 ± 3.48 kg of fruits per tree. Tree diameter, height, and the number of branches influence the fruit yield of S. guineense. Overall, the species needs effective management strategies to sustain its population.