Charles S. Wortmann

Charles S. Wortmann


·Atlas of Sorghum Production in Eastern & Southern Africa

Charles S. Wortmann


B.S. in Agronomy, University of Nebraska, 1972

M.S. in Soil Science, University of Nebraska, 1978

Ph.D. in Crop Science, University of Nebraska, 1987

Area of Focus

Soil Science


Sustainable Land Resource Management

High Yield Soybean Production

TOT in Uganda

Optimizing Fertilizer Use in Uganda

Nitrogen Loss Assessment Tool (N-LAT)

Land Application of Novozyme Spent Biomass

Research Interests

Improved nitrogen and phosphorus management for improved nutrient use efficiency, water quality protection, and reduced nitrous oxide emissions in Nebraska's agriculture; and improving soil and water management for crop production in sub-Saharan Africa.

Major Project Activities

Research and extension for more profitable and environmentally safe nutrient management in Nebraska, and support to soil fertility management research and extension in sub-Saharan Africa.

Extension Interests

Soil fertility management, nutrient management planning, manure use, water quality protection, climate change issues, and optimizing fertilizer use in Africa.

Other Experience

Twenty years of agricultural research and extension experience in Africa; fluent in Swahili.


  • Wortmann, C.S., M. Milner, K.C. Kaizzi, N. Maman, R.A. Cyamweshi, M.K. Dicko, C. Kibunja, M. Macharia, R. Maria, P. Nalivata, D. Negash, D. Nkonde, K. Ouattara, C.J. Senkoro, B.D. Tarfa, F.M. Tetteh. 2017. Maize-nutrient response information applied across Sub-Saharan Africa. Nutr. Cycl. Agroecosyst. 107:175-186.
  • Wortmann, C.S., J.P. Garcia, C.A. Shapiro, T.M. Shaver, R.B. Ferguson, B. Maharjan, H. Blanco, S. Ruis, and R.S. Little. 2017. Soil management for increased soil organic matter. NebGuide G2283.
  • Wortmann, C., C. Kubik, R. Little, C. Shapiro, and C Francis. 2017 Planning the transition to organic crop production UNL NebGuide. G2282.
  • Nalivata, P., C. Kibunja, J. Mutegi, F. Tetteh, B. Tarfa, M.K. Dicko, K. Ouattara, R.A. Cyamweshi, M.K. Nouri, W. Bayu and C.S. Wortmann. 2017. Integrated Soil Fertility Management in Sub-Saharan Africa. Fertilizer Use Optimization in sub-Saharan Africa Charles S. Wortmann and Keith Sones (ed). Published by CABI, UK..
  • Wortmann, C.S., M. Milner and G.B. Tesfahunegn. 2017. Spatial Analysis for Optimization of Fertilizer Use. Fertilizer Use Optimization in sub-Saharan Africa. Charles S. Wortmann and Keith Sones (ed). Published by CABI, UK.
  • Nansamba, A., K.C. Kaizzi, A.B. Twaha, P. Ebanyat and C.S. Wortmann. 2016. Reduced tillage, rotation, and soil fertility management for sorghum production in Uganda. Agron. J. 108:1-10.
  • Wortmann, C., P. Grassini and R. W. Elmore. 2016. ‘Optimizing maize-based cropping systems: sustainability, good agricultural practices (GAP) and yield goals’, in Watson, D. (ed.), Achieving sustainable cultivation of maize Volume 2: Cultivation techniques, pest and disease control, Burleigh Dodds Science Publishing, Cambridge, UK (ISBN: 978 1 78676 012 8;
  • Wortmann, C.S. and C.K. Kaizzi. 2015. Optimization of financially constrained fertilizer use. In A. Chatterjee and D. Clay (ed) Soil Fertility Management in Agroecosystems, ASA, CSSA, and SSSA, Madison, WI.
  • Wortmann, C.S., C.A. Shapiro, and M. Schmer. 2015. Residue harvest effects on irrigated, no-till corn yield and nitrogen response. Agron. J. 108:384-390.
  • Liben, F., K. Tesfaye, and C.S. Wortmann. 2015. Dry soil planting of maize for variable onset of rains in Ethiopia. Agron J. 107:1618-1625.
  • Liben, F., C.S. Wortmann, and K.T. Fantaye. 2015. Risks associated with dry soil planting time in Ethiopia. Intern. J. Agric. Agron. Res. 6:14-23.

Complete publication list (PDF file).

Book Publication