Evaluating mulching materials to enhance seedling survival and growth in dry-lowland and frost prone highland agroecologies of Eastern Amhara Ethiopia

Climate change and variability is impacting the forestry sector, particularly saplings survival at different growth stages. Effective adaptation strategies including application of mulching are essential for improving SS and increasing forest cover. However, the effects of various mulching materials and thicknesses on saplings survival across different agroecological zones in Eastern Amhara, Ethiopia, remain limited. This study aimed to identify the best mulching materials and thicknesses for saplings survival in water-stressed areas (Kobo) and frost-prone areas (Guguftu). Casuarina equisetifolia and Hagenia abyssinica seedlings were evaluated using crop residues and grass at 5 and 10 cm thicknesses, compared to a no-mulch where the experiment was laid in RCBD with three replications. Results showed significant variations were observed among the mulching materials and their respective thicknesses in the survival and growth of seedlings. For C. equisetifolia in Kobo, the crop residue mulch with a thickness of 10 cm demonstrated the considerable maximum growth performance (height 5.23 m, diameter 5.1 cm) and the highest survival rate (96.3%). H. abyssinica height (1.23 m) showed significant growth differences in Guguftu experimental locations, although survival and diameter did not show significant variations. Seedlings treated with mulch showed significantly better performance than the control group, highlighting the vital role of mulching in conserving soil moisture in lowland areas and providing frost protection in highland regions. Finally, the study recommends applying a 10 cm layer of mulch in both zones to improve seedling survival–an essential step toward the success of national reforestation efforts and broader global environmental initiatives.