Ethiopia occupies the interior of the Horn of Africa, stretching between 3° and 15°N and 33° and 48°E (Figure 2.1). It covers a total area of 1.13 million km2

(CSA, 2000) that spans over a wide range of altitude, from 110m below sea level to over 4600m above sea level (asl). The wide altitudinal coverage enhances the diversity of climate, topography, soil, and thus vegetation resources. Ethiopia is the second most populous country in sub-Saharan Africa, with 74 million people, and 84 per cent of these live in rural areas (CSA, 2008), depending mainly on mixed crop/animal and forest/tree production for livelihoods.