Dr. Keith Janssen
- Ph.D. Soil Science, Michigan State University, 1973
- M.S. Soil Science, University of Nebraska, Lincoln, 1967
- B.S. Technical Agriculture, University of Nebraska, Lincoln, 1965
- Loecker, J.L., N.O. Nelson, W.B. Gordon, L.D. Maddux, K.A. Janssen, and W.T. Schapaugh. 2010. Manganese response in conventional and glyphosate resistant soybean. Agron. J. 102:606-611.
- Sonmez, O., G.M. Pierzynski, L. Frees, B. Davis, D. Leikam. D.W. Sweeney, and K.A. Janssen. 2009. A field-based assessment tool for phosphorus losses in runoff in Kansas. Journal of Soil and Water Conservation 64:(3) 212-222.
- Maski, D., R. Mankin, K.A. Janssen, P. Tuppard, and G.M. Pierzynski. 2008. Modeling runoff and sediment yields from combined in-field crop practices using the Soil and Water Assessment Tool. Journal of Soil and Water Conservation 63:(4) 193-203.
Soil Management & Conservation
Full-width tillage of the soil with broadcast incorporation of fertilizers has been the mainstay for row crop production in east central and southeast Kansas for many years. This practice has lead to excessive soil erosion, depletion of soil organic matter, and elevated levels of sediment and nutrients in surface waters. Adoption of no-till in these areas has been slow because of frequent spring rainfall and imperfectly drained soils.
The focus of my research has been to evaluate different tillage, fertilization, and planting options to determine which combinations of practices perform best for growing crops on imperfectly drained soils and also protect natural resources and the environment.
- Collection of runoff water at field edges to measure the levels of sediment, nutrient, and herbicide losses occurring with no-till, strip-till, and conventional-tillage systems.
- Evaluation of nitrogen rates and starter fertilizer for strip-till corn.
- Assessment of the performance of various P enhancement products.
- Assessment of the impact of planting corn on top of strip-till furrows versus off the row.
- Evaluation of the effects of yearly and long-term harvesting of crop residues on soil properties and crop yields.
- On-farm yield comparisons with strip-till, no-till, and conventional tillage systems for corn at various locations, from the Oklahoma border to the Kansas River Valley in eastern Kansas.
- Trials to determine if sulfur, zinc, and magnesium fertilizers are needed when growing crops no-till.
- Analysis of soil profiles to determine the impact of continuously banding fertilizers in the same soil zone on residual nutrient buildup, non-added nutrient depletion, and acidity.