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.


  • Mortzinis, S., G. Kaur, J. Orlowski, C. Shapiro, C. Lee, C. Wortmann, D. Holshouser, E. Nafziger, H. Kandel, J. Niekamp, J. Ross, J. Lofton, J. Vonk, K. Roozeboom, K. Thelen, L. Lindsey, M. Staton, S. Naeve, S. Casteel, W. Wiebold, and S. Conley. 2017. Soybean response to nitrogen application across the United States: a synthesis-analysis. Field Crops Res. 2015:74-82.
  • Senkoro, C.J., A.E. Marandu, G.J. Ley, and C.S. Wortmann. 2017. Maize and pigeon pea sole crop and intercrop nutrient response functions for Tanzania. Nutr. Cycl. Agroecosys. 109:303–314. DOI 10.1007/s10705-017-9889-z
  • Liben, F.M., S.J. Hassan, B.T. Weyesa, C.S. Wortmann, H.K. Kim, M.S. Kidane, G.G. Yeda, and B. Beshir. 2017. Conservation agriculture for maize and bean production in the Central Rift Valley of Ethiopia. Agron. J. 109:1-10 doi:10.2134/agronj2017.02.0072
  • Maman, N., M. Dicko, G. Abdou, G. and C. Wortmann. 2017. Sorghum and groundnut sole and intercrop nutrient response in semi-arid West Africa. Agron. J. 109:1-11. doi:10.2134/agronj2017.02.0120
  • Tarfa, B.D., N. Maman, K. Ouattara, and C. Wortmann. 2017. Groundnut and soybean response to nutrient application in West Africa. Agron. J. 109:2323-2332 doi:10.2134/agronj2017.03.0132
  • Maman, N., MK Dicko, G. Abdou, Z. Kouyaté, and C. Wortmann. 2017. Pearl millet and cowpea intercrop response to applied nutrients in West Africa. Agron. J. 109:2333-2342. doi:10.2134/agronj2017.03.0139
  • Blanco-Canqui, H., and C.S. Wortmann. 2017. Crop residue removal and soil erosion by wind. J. Soil Water Conserv. 72:97A-104A. doi:10.2489/jswc.72.5.
  • Blanco-Canqui, H., M. Sindelar, C. Wortmann, and G. Kreikemeier. 2017. Aerial interseeded cover crop and corn residue harvest: soil and crop impacts. Agron J 109:1344-1351. doi:10.2134/agronj2017.02.0098
  • Ndungu-Magiroi, K.W., C.S. Wortmann, C. Kibunja, C. Senkoro, T.J.K. Mwangi, D. Wamae, M. Kifuko-Koech, and J. Msakyi. 2017. Maize bean intercrop response to nutrient application relative to maize sole crop response. Nutr. Cycl. Agroecosys 109:17-27. Doi: 10.1007/s10705-017-9862-x
  • Ndungu-Magiroi, K.W., A. Kasozi, K.C. Kaizzi, T. Mwangi, M. Koech, C.N. Kibunja, D. Wamae and C.S. Wortmann. 2017. Finger millet response to nitrogen, phosphorus and potassium in Kenya and Uganda. Nutr. Cycl. Agroecosys. 108:297-308. Doi: 10.1007/s10705-017-9857-7
  • Baffaut, C., N.O. Nelson, J.A. Lory, A. Senaviratne, A. Bhandari, R. Udawatta, D. Sweeney, M. Helmers, M. Van Liew, A. Mallarino, and C. Wortmann. 2017. Multi-site evaluation of APEX for water quality: 1. Best professional judgement. JEQ. doi: 10.2134/jeq2016.06.0226.
  • Nelson, N.O, C. Baffaut, C., J.A. Lory, A. Senaviratne, A. Bhandari, R. Udawatta, D. Sweeney, M. Helmers, M. Van Liew, A. Mallarino, and C. Wortmann. 2017. Multi-site evaluation of apex for water quality: ii regional parameterization. JEQ doi: 10.2134/jeq2016.07.0254
  • Alemayehu, A., T. Tamado, D. Nigussie, D. Zigzaw, T. Kinde, and C. Wortmann. 2017. Maize-common bean intercropping to optimize maize-based crop production. J. Agric. Sci. p 1-13. doi:10.1017/S0021859617000193
  • 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.
  • Abunyewa, A., C.S. Wortmann et al. 2016. Grain sorghum leaf reflectance and nitrogen use. Afr. J. Agric. Res. 11:825-836.
  • Van Liew, M.W., C.S. Wortmann, D.N. Moriasi, K.W. King, D.C. Flanagan, T.L. Veith, G.W. McCarty, D.B. Bosch, and M.D. Tomer, 2016. Simulating streamflow and water quality in crop production areas of the United States. ASABE. 60:123-146.
  • Tesfahunegn, G.B. and C.S. Wortmann. 2016. Maize [Zea Mays (L.)] crop-nutrient response functions extrapolation for Sub-Saharan Africa. Nutr. Cycl. Agroecosyst. 109:269-289. DOI 10.1007/s10705-017-9887-1
  • Alemayehu Assefa, Tamado Tana, Nigusie Dechassa, Yigzaw Dessalgn, Kinde Tesfaye and Wortmann C.S. 2016. Maize-common bean/lupine intercrop productivity and profitability in maize based cropping systems of Northwestern Ethiopia. Ethiop. J. Sci. Technol. 9:69-85.
  • 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