Challenges and a Strategy for Successful Restoration of Dry Evergreen Afromontane Forests of Ethiopia

Dry evergreen Afromontane forests (DAF) once covered most of the Ethiopian highlands. Currently, they are found as a few patches. DAF restoration is a national forest restoration priority in Ethiopia. It has also been identified to be among global ecosystem restoration priorities. There are sufficient data to show DAF restoration from the soil seed bank or seed rain is hardly possible. Planting trees from multiple provenances is important to restore climate-resilient DAF. Therefore, DAF restoration cannot be achieved through natural regeneration alone and must be accomplished by planting characteristic DAF tree species. The poor soil moisture and nutrient conditions in Ethiopia's dry highlands result in low native tree seedling survival and growth. Hence, proper preparation of the planting sites and after-planting seedling care for at least two years is a reliable mechanism for achieving successful survival and growth. Along with seedling care after planting, four additional mechanisms discussed in this review (i.e., the use of nurse trees/shrubs, design of nursery practices, inoculation with arbuscular mycorrhizal fungi, and application of biochar) have also been shown to be useful. However, they cannot substitute for proper planting site preparation and post-planting seedling care. The complementary use of these five mechanisms could further enhance success. However, there are more questions than answers regarding the effectiveness of the five mechanisms discussed. We hope this review will motivate researchers to engage further to answer some of the important questions regarding restoration success.