8. Ethiopia alone accounts for about 50% of the total highland zone in tropical Africa. The highlands zone represents 40% of the total land mass of the country where well over 80% of the human and 75% of the total livestock population are found. The central highlands on which this paper focuses constitute about 26% of the total highland area in the country. The central highlands are characterized by an altitude ranging from 18002700 m.a.s.l. and an annual precipitation of 700-1200 mm with an estimated growing period of 150-300 days, and a mean temperature of 13-19°C. Vertisols and cambisols are the most pervasive soil types in the region. Mixed farming is the dominant production system in these areas. (Assefa, 1989, drawing from various sources).
9. The major grain and livestock producing regions of the country - Arsi, Gojjam and Shoa - make up nearly 50% of the central highlands. Approximately 64% of the total area of Arsi, 54% of Gojjam and 38% of Shoa are regarded as high potential mixed farming areas. In these regions, about 85% of the rural population is engaged in traditional mixed farming, while only 13.6% and 1.4% are estimated to specialize in crop and livestock production respectively. (PPD/MOA, 1984).
