Effect of pruning treatment on the growth of woody pioneers under exclosure management in Tigray, Ethiopia

Pruning is a widely applied silvicultural practice that can enhance woody plant growth and improve exclosure productivity. This study quantified the effects of pruning intensity on growth, biomass accumulation, seedling regeneration, and grass cover in exclosures. Four treatments were applied: control (no pruning), 25%, 35%, and 50% branch removal. Tree growth was assessed using diameter at breast height (DBH), diameter at stump height (DSH), height, and crown diameter. Biomass increased significantly with pruning, though responses varied by species: V. etbaica and O. europaea showed maximum gains under 35% pruning (13.1% and 58.1% increases, respectively), while E. racemosa and J. procera responded best to 25% pruning (3.8% and 68.1% increases, respectively). Seedling regeneration also differed among species: O. europaea and J. procera achieved greater heights under 25% pruning, while D. viscosa and S. kunthianum performed best under 50% pruning. Grass cover increased significantly at the Kihen and Tukul sites, with the highest cover recorded under 50% pruning at Kihen, whereas no improvement was observed at Mugulat due to denser canopy conditions. Overall, moderate pruning (25–35%) enhanced tree biomass and seedling growth, while intensive pruning (50%) favored grass cover under open-canopy conditions. These findings highlight the importance of species-specific and site-tailored pruning regimes to optimize forest restoration outcomes and balance multiple management objectives in exclosures.