Indigenous Woody Species Regeneration under the Canopies of Exotic Tree Plantations at Tore Forest, Gelana District, Southern Oromia, Ethiopia

Ethiopia has one of the longest forest plantation histories in Africa. Forest plantations in Ethiopia are mainly monocultures of exotic species, such as Eucalyptus globulus, Eucalyptus camaldulensis, Cupressus lusitanica, Casuarina cunninghamiana, Pinus patula, Pinus radiata, and the native species Juniperus procera. Accordingly, in the end of the 19th century Eucalyptus species were introduced to satisfy the high demand of firewood [1,2]. In addition to this, in the year 2005 it was estimated that Ethiopia had 509000 hectares of plantations, mainly monocultures, of Eucalyptus, Cupressus and Pinus species and 20000 hectares more were expected to be established by the year 2010 [3]. Forests provide a habitat for uncounted creatures and microorganisms, and over millions of people also depends on them for timber production, firewood, fruit, resins and other products. Appropriate monoculture plantation of fast-growing species like Eucalyptus species, Acacia, Teak, Poplar, etc., has demonstrated to be one of relevant approach for afforestation programs, both in economic and ecological purposes, particularly, the only effective obtion to initially reforest the degraded areas, then to transform into permanent forest [4]. During recent years, the planting of large areas of fast growing trees species has set off much controversy, especially in the developing world. Critics of these “fast-wood” plantations include environmentalists, who argue that they are substituting natural forests and causing harm to wildlife, water bodies and the soil, and local communities, who complain that plantations are taking over land which previously provided them with the means to feed themselves and earn a living [5]. Whereas, plantations have been suggested to promote native plant species understory regeneration, and thus increase biodiversity [6-9]. The mechanisms that encourage the understory regeneration involves shading off grasses, enhancing soil nutrients (through uptake by deep roots and litter fall), bettering micro-climate, and in general increasing the chance for seed germination and establishment, which an area of highly degraded sites [8]. Furthermore, plantations can also protect sites from further degradation by preventing soil erosion and reducing fire hazard. For these reasons, trees of exotic or native origin are Volume 2 Issue 1 2018