Soil Fertility Status and Numass Fertilizer Recommendation of Typic Hapluusterts in the Northern Highlands of Ethiopia

Nutrient depletion is one of the major causes that contribute to decline in soil productivity in the highlands of Ethiopia. It is generally a reversible constraint as long as soil test based fertilizer application is in place. However, Ethiopian subsistence agriculture has suffered for years due to lack of proper knowledge to combat nutrient depletion. To date, blanket application is the traditional approach for applying commercial fertilizers irrespective of soil types and agroecology. Thus, it is imperative to start to develop an agro-ecology based soil test program for small holding farmers. This study assesses the soil fertility status of Typic Hapluusterts and suggests application of NuMaSS as a diagnostic tool to recommend supplementary N and P fertilizers for maize at limiting sites. In total thirty-six soil samples were collected from five profiles and analyzed for the major soil physical and chemical properties. The study reveals that N, P and micronutrients are deficient in all the sampled profiles. Based on the soil analytical data and farmers’ soil fertility management practices, the study proposes that a quarter, half or the lower confident limit of the NuMaSS prescribed fertilizer 213 kg P ha and 104 kg N ha for Adigudom; 161 kg P ha and 98 kg N ha for Adwa; 132 kg P ha and 1 1 1 1 1 111 kg N ha for Wukro; 218 kg P ha and 106 kg N ha for Shire; and 149 kg P ha and 115 kg N ha for 1 1 1 1 1 Maychew should be used as a supplement.