JOHN L KOVAR
Soil and Water Quality Research
Soil Scientist
Phone: (515) 294-3419
Fax: (515) 294-8125
Room 305 2110 UNIVERSITY BOULEVARD
AMES, IA, 50011-0000
Haan, M.M., Russell, J.R., Kovar, J.L., Nellesen, S.L. 2007. Effects of grazing management on stream bank erosion [abstract]. American Forage and Grassland Council Conference Proceedings. 16:18.
Tomer, M.D., Moorman, T.B., Kovar, J.L., James, D.E., Burkart, M. 2007. Spatial Patterns of Sediment and Phosphorus in a Riparian Buffer, Western Iowa. Journal of Soil and Water Conservation. 62(5):329-338.
Kleinman, P.J., Sullivan, D., Wolf, A., Brandt, R., Dou, Z., Elliott, H., Kovar, J.L., Leytem, A.B., Maguire, R., Moore Jr, P.A., Sharpley, A.N., Shober, A., Sims, T., Toth, J., Toor, G., Zhang, H., Zhang, T., Saporito, L.S. 2007. Selection of a Water-Extractable Phosphorus Test for Manures and Biosolids as an Indicator of Runoff Loss Potential. Journal of Environmental Quality. 36(5):1357-1367.
Kelly, J.M., Kovar, J.L., Sokolowsky, R., Moorman, T.B. 2007. Phosphorus Uptake During Four Years by Different Vegetative Cover Types in a Riparian Buffer. Nutrient Cycling in Agroecosystems. 78:239-251.
Sullivan, D., Kleinman, P.J., Wolf, A., Brandt, R., Dou, Z., Elliott, H., Kovar, J.L., Leytem, A.B., Maguire, R., Moore Jr, P.A., Sharpley, A.N., Shober, A., Sims, J.T., Toor, G., Zhang, H., Zhang, T. 2006. Standardizing the water-soluble phosphorus test for manures and biosolids. ASA-CSSA-SSSA Annual Meeting Abstracts.
Karlen, D.L., Kovar, J.L. 2006. No-till corn response to banded K on Des Moines lobe soils. In: Fluid Fertilizer Foundation Symposium Proceedings. Fluid Feritlizer Forum 2006, February 12-14, 2006, Scottsdale, AZ. 2006 CD-ROM
Wortmann, C., Helmers, M., Mallarino, A., Barton, C., Devlin, D., Pierzynski, G., Lory, J., Massey, R., Holz, J., Shapiro, C., Kovar, J.L. 2006. Phosphorus management and water quality protection. Heartland Water Quality Workgroup, Regional Workgroup Bulletin. In: The Midwest (RP187) Lincoln; University of Nebraska Press. p.23.
Kovar, J.L. 2005. What limits phosphorus fertilizer efficiency [CD-ROM]? In: ASA-CSSA-SSSA Annual Meeting Abstracts, Nov. 6-10, 2005, Salt Lake City, UT.
Kovar, J.L., Claassen, N. 2005. Plant growth and phosphorus uptake kinetics of three riparian grass species [abstract]. ASA-CSSA-SSSA Annual Meeting Abstracts. ASA-CSSA-SSSA Annual Meeting. Nov. 6-10, 2005, Salt Lake City, UT.
Moeller, S.L., Kovar, J.L., Russell, J.R. 2005. Potential phosphorus losses from streambanks in grazing lands [CD-ROM]. In: ASA-CSSA-SSSA Annual Meeting Abstracts, Nov. 6-10, 2005, Salt Lake City, UT.
Schroeder, P.D., Kovar, J.L. 2005. Comparison of phosphorus sorption and desorption from an established buffer and adjacent production field [CD-ROM]. In: ASA-CSSA-SSSA Annual Meeting Abstracts, Nov. 6-10, 2005, Salt Lake City, UT.
Baum, K., Pierzynski, G., Kleinman, P.J., Kovar, J.L., Maguire, R., Moore Jr, P.A., Zhang, T. 2006. Evaluating the influence of storage time, sample handling method, and filter paper on the measurement of water extractable phosphorus in animal manures. Communications in Soil Science and Plant Analysis. 37:451-463.
Schroeder, P.D., Kovar, J.L. 2006. Comparison of organic and inorganic phosphorus fractions in an established buffer and adjacent production field. Communications in Soil Science and Plant Analysis. 37:1219-1232.
Zaimes, G.N., Schultz, R.C., Isenhart, T.M., Mickelson, S.K., Kovar, J.L., Russell, J.R., Powers, W.J. 2005. Stream bank erosion under different riparian land-use practices in northeast Iowa. In: Proceedings of the North American Agroforestry Conference. 9th North American Agroforestry Conference, June 12-15, 2005, Rochester, MN. 2005 CD-ROM.
Baum, K., Pierzynski, G., Kleinman, P.J., Kovar, J.L., Maguire, R., Moore Jr, P.A., Zhang, T. Evaluating the Influence of Storage Time, Sample-handling Method, and Filter Paper on the Measurement of Water-Extractable Phosphorus in Animal Manures. Communications in Soil Science and Plant Analysis. 37(3-4):451-463.
Kovar, J.L., Kelly, J.M., Schroeder, P.D., Wang, Z.Y. 2005. In-situ dynamics of four macronutrients in the rhizosphere soil solution of maize, switchgrass, and cottonwood. In: Hartmann, A., Schmid, M., Wenzel, W., and Hinsinger, P., editors. 2004 Rhizosphere, Perspectives and Challenges - A Tribute to Lorez Hiltner, September 12-17, 2004, Neuherberg, Germany. p. 192.
Kovar, J.L., Claassen, N. 2005. Soil-root interactions and phosphorus nutrition of plants. Book Chapter. In: Sims, J.T. and Sharpley, A.N., editors. Phosphorus: Agriculture and the Environment. Madison, WI: ASA-CSSA-SSSA. p 379-414.
Wang, Z., Kelly, J.M., Kovar, J.L. 2005. Rhizosphere solution chemistry and the nutrient status of juvenile corn, cottonwood, and switchgrass plants. Plant and Soil Journal. 270:213-221.
Kovar, J.L., Schroeder, P.D., Washburn, Jr., K.L. 2004. Positional availability of phosphorus from surface fertilizer bands. In: A.J. Schlegel (ed.). Proceedings of Great Plains Soil Fertility Conference. March 2-3, 2004, Kansas State University, Manhattan, KS. p. 271-276.
KOVAR, J.L. STARTER COMPOSITION AND HYBRID SELECTION AFFECT EARLY GROWTH AND YIELD OF CORN. FLUID FERTILIZER FOUNDATION SYMPOSIUM PROCEEDINGS. 2004. V. 21. P. 131-141.
Wang, Z., Kelly, J.M., Kovar, J.L. 2004. In situ dynamics of phosphorus in the rhizosphere solution of five species. Journal of Environmental Quality. 33:1387-1392.
KOVAR, J.L. EFFICIENT USE OF NUTRIENTS - ARE WE IGNORING THE HIDDEN HALF OF THE CROP?. ASA-CSSA-SSSA ANNUAL MEETING ABSTRACTS. 2003. CD-ROM. MADISON, WI.
GASTON, L.A., KOVAR, J.L., SAUER, T.J. PREDICTING PHOSPHORUS LOSS IN RUNOFF USING A DISPLACEMENT TECHNIQUE. ASA-CSSA-SSSA ANNUAL MEETING ABSTRACTS. 2003. CD-ROM. MADISON, WI.
KOVAR, J.L. METHODS OF DETERMINATION OF P, K, CA, MG, AND TRACE ELEMENTS. BOOK CHAPTER. 2003. AVAILABLE FROM: WWW.UWEX.EDU/CES/PUBS/PDF/A3769.PDF. UW EXTENSION.
KOVAR, J.L. EFFECTIVE STARTER FERTILIZERS FOR CORN IN CONSERVATION TILLAGE SYSTEMS. FLUID FERTILIZER FOUNDATION SYMPOSIUM PROCEEDINGS. 2003. V. 20. P. 230-240.
KOVAR, J.L., SAUER, T.J., MOORMAN, T.B. TURKEY LITTER AS A PHOSPHORUS SOURCE FOR CORN. AMERICAN SOCIETY OF AGRONOMY MEETINGS. 2002. CD-ROM. MADISON, WI.
KELLY, J.M., BURKART, M.R., KOVAR, J.L., MOORMAN, T.B., LOGSDON, S.D. AN ECONOMICALLY SUSTAINABLE RIPARIAN BUFFER TO PROMOTE BANK STABILITY AND REDUCE PHOSPHORUS LOSS IN THE LOESS HILLS. AMERICAN SOCIETY OF AGRONOMY. 2002. CD-ROM. MADISON, WI.
GASTON, L.A., EILERS, T.L., KOVAR, J.L., COOPER, D., ROBINSON, D.L. GREENHOUSE AND FIELD STUDIES ON HAY HARVEST TO REMEDIATE HIGH PHOSPHORUS SOIL. COMMUNICATION IN SOIL SCIENCE PLANT ANALYSIS. 2003. V. 34. p. 2085-2097.
AHMED, S., MICKELSON, S.K., RUSSELL, J.R., POWERS, W.J., SCHULTZ, R.C., KOVAR, J.L. IMPACT OF DIFFERENT GRAZING SYSTEMS AND VEGETATIVE FILTER STRIPS ON SEDIMENT AND NUTRIENT LOSSES WITH SURFACE RUNOFF. AGRICULTURAL ENGINEERING INTERNATIONAL CONFERENCE PROCEEDINGS. 2002. PAPER NO. 022141.
HAAN, M.M., RUSSELL, J.R., POWERS, W.J., MICKELSON, S.K., KOVAR, J.L., SCHULTZ, R.C. EFFECTS OF GRAZING MANAGEMENT ON SEDIMENT AND PHOSPHORUS RUNOFF. AMERICAN FORAGE AND GRASSLAND COUNCIL PROCEEDINGS. 2002. V. 11. P. 292-296.
POWERS, W., RUSSELL, J., HAAN, M., SCHULTZ, R., STAUFFER, E., ZAIMES, G., HUNKINS, B., KOVAR, J.L., BOEHM, J., MICKELSON, S. GRAZING SYSTEMS TO MAXIMIZE FORAGE AND MINIMIZE P, N, AND SEDIMENT POLLUTION OF STREAMS. AGRICULTURAL AND ENVIRONMENT CONFERENCE PROCEEDINGS. 2003. P. 23-35.
KOVAR, J.L. FACTORS AFFECTING N AND P NEEDS IN STARTERS: FORMULATIONS AND PLACEMENT FOR REDUCED-TILLAGE CORN. FLUID FERTILIZER FOUNDATION SYMPOSIUM PROCEEDINGS. 2002. V. 19. P. 12-20.